1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/generic/nsGfxScrollFrame.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,4599 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +/* rendering object to wrap rendering objects that should be scrollable */
1.10 +
1.11 +#include "nsGfxScrollFrame.h"
1.12 +
1.13 +#include "base/compiler_specific.h"
1.14 +#include "DisplayItemClip.h"
1.15 +#include "nsCOMPtr.h"
1.16 +#include "nsPresContext.h"
1.17 +#include "nsView.h"
1.18 +#include "nsIScrollable.h"
1.19 +#include "nsContainerFrame.h"
1.20 +#include "nsGkAtoms.h"
1.21 +#include "nsNameSpaceManager.h"
1.22 +#include "nsContentList.h"
1.23 +#include "nsIDocumentInlines.h"
1.24 +#include "nsFontMetrics.h"
1.25 +#include "nsBoxLayoutState.h"
1.26 +#include "nsINodeInfo.h"
1.27 +#include "nsScrollbarFrame.h"
1.28 +#include "nsIScrollbarMediator.h"
1.29 +#include "nsITextControlFrame.h"
1.30 +#include "nsIDOMHTMLTextAreaElement.h"
1.31 +#include "nsNodeInfoManager.h"
1.32 +#include "nsContentCreatorFunctions.h"
1.33 +#include "nsAutoPtr.h"
1.34 +#include "nsPresState.h"
1.35 +#include "nsIHTMLDocument.h"
1.36 +#include "nsContentUtils.h"
1.37 +#include "nsLayoutUtils.h"
1.38 +#include "nsBidiUtils.h"
1.39 +#include "mozilla/ContentEvents.h"
1.40 +#include "mozilla/EventDispatcher.h"
1.41 +#include "mozilla/Preferences.h"
1.42 +#include "mozilla/LookAndFeel.h"
1.43 +#include "mozilla/dom/Element.h"
1.44 +#include <stdint.h>
1.45 +#include "mozilla/MathAlgorithms.h"
1.46 +#include "FrameLayerBuilder.h"
1.47 +#include "nsSMILKeySpline.h"
1.48 +#include "nsSubDocumentFrame.h"
1.49 +#include "nsSVGOuterSVGFrame.h"
1.50 +#include "mozilla/Attributes.h"
1.51 +#include "ScrollbarActivity.h"
1.52 +#include "nsRefreshDriver.h"
1.53 +#include "nsThemeConstants.h"
1.54 +#include "nsSVGIntegrationUtils.h"
1.55 +#include "nsIScrollPositionListener.h"
1.56 +#include "StickyScrollContainer.h"
1.57 +#include "nsIFrameInlines.h"
1.58 +#include "gfxPrefs.h"
1.59 +#include <algorithm>
1.60 +#include <cstdlib> // for std::abs(int/long)
1.61 +#include <cmath> // for std::abs(float/double)
1.62 +
1.63 +using namespace mozilla;
1.64 +using namespace mozilla::dom;
1.65 +using namespace mozilla::layout;
1.66 +
1.67 +//----------------------------------------------------------------------
1.68 +
1.69 +//----------nsHTMLScrollFrame-------------------------------------------
1.70 +
1.71 +nsIFrame*
1.72 +NS_NewHTMLScrollFrame(nsIPresShell* aPresShell, nsStyleContext* aContext, bool aIsRoot)
1.73 +{
1.74 + return new (aPresShell) nsHTMLScrollFrame(aPresShell, aContext, aIsRoot);
1.75 +}
1.76 +
1.77 +NS_IMPL_FRAMEARENA_HELPERS(nsHTMLScrollFrame)
1.78 +
1.79 +nsHTMLScrollFrame::nsHTMLScrollFrame(nsIPresShell* aShell, nsStyleContext* aContext, bool aIsRoot)
1.80 + : nsContainerFrame(aContext),
1.81 + mHelper(ALLOW_THIS_IN_INITIALIZER_LIST(this), aIsRoot)
1.82 +{
1.83 +}
1.84 +
1.85 +void
1.86 +nsHTMLScrollFrame::ScrollbarActivityStarted() const
1.87 +{
1.88 + if (mHelper.mScrollbarActivity) {
1.89 + mHelper.mScrollbarActivity->ActivityStarted();
1.90 + }
1.91 +}
1.92 +
1.93 +void
1.94 +nsHTMLScrollFrame::ScrollbarActivityStopped() const
1.95 +{
1.96 + if (mHelper.mScrollbarActivity) {
1.97 + mHelper.mScrollbarActivity->ActivityStopped();
1.98 + }
1.99 +}
1.100 +
1.101 +nsresult
1.102 +nsHTMLScrollFrame::CreateAnonymousContent(nsTArray<ContentInfo>& aElements)
1.103 +{
1.104 + return mHelper.CreateAnonymousContent(aElements);
1.105 +}
1.106 +
1.107 +void
1.108 +nsHTMLScrollFrame::AppendAnonymousContentTo(nsBaseContentList& aElements,
1.109 + uint32_t aFilter)
1.110 +{
1.111 + mHelper.AppendAnonymousContentTo(aElements, aFilter);
1.112 +}
1.113 +
1.114 +void
1.115 +nsHTMLScrollFrame::DestroyFrom(nsIFrame* aDestructRoot)
1.116 +{
1.117 + DestroyAbsoluteFrames(aDestructRoot);
1.118 + mHelper.Destroy();
1.119 + nsContainerFrame::DestroyFrom(aDestructRoot);
1.120 +}
1.121 +
1.122 +nsresult
1.123 +nsHTMLScrollFrame::SetInitialChildList(ChildListID aListID,
1.124 + nsFrameList& aChildList)
1.125 +{
1.126 + nsresult rv = nsContainerFrame::SetInitialChildList(aListID, aChildList);
1.127 + mHelper.ReloadChildFrames();
1.128 + return rv;
1.129 +}
1.130 +
1.131 +
1.132 +nsresult
1.133 +nsHTMLScrollFrame::AppendFrames(ChildListID aListID,
1.134 + nsFrameList& aFrameList)
1.135 +{
1.136 + NS_ASSERTION(aListID == kPrincipalList, "Only main list supported");
1.137 + mFrames.AppendFrames(nullptr, aFrameList);
1.138 + mHelper.ReloadChildFrames();
1.139 + return NS_OK;
1.140 +}
1.141 +
1.142 +nsresult
1.143 +nsHTMLScrollFrame::InsertFrames(ChildListID aListID,
1.144 + nsIFrame* aPrevFrame,
1.145 + nsFrameList& aFrameList)
1.146 +{
1.147 + NS_ASSERTION(aListID == kPrincipalList, "Only main list supported");
1.148 + NS_ASSERTION(!aPrevFrame || aPrevFrame->GetParent() == this,
1.149 + "inserting after sibling frame with different parent");
1.150 + mFrames.InsertFrames(nullptr, aPrevFrame, aFrameList);
1.151 + mHelper.ReloadChildFrames();
1.152 + return NS_OK;
1.153 +}
1.154 +
1.155 +nsresult
1.156 +nsHTMLScrollFrame::RemoveFrame(ChildListID aListID,
1.157 + nsIFrame* aOldFrame)
1.158 +{
1.159 + NS_ASSERTION(aListID == kPrincipalList, "Only main list supported");
1.160 + mFrames.DestroyFrame(aOldFrame);
1.161 + mHelper.ReloadChildFrames();
1.162 + return NS_OK;
1.163 +}
1.164 +
1.165 +nsSplittableType
1.166 +nsHTMLScrollFrame::GetSplittableType() const
1.167 +{
1.168 + return NS_FRAME_NOT_SPLITTABLE;
1.169 +}
1.170 +
1.171 +nsIAtom*
1.172 +nsHTMLScrollFrame::GetType() const
1.173 +{
1.174 + return nsGkAtoms::scrollFrame;
1.175 +}
1.176 +
1.177 +/**
1.178 + HTML scrolling implementation
1.179 +
1.180 + All other things being equal, we prefer layouts with fewer scrollbars showing.
1.181 +*/
1.182 +
1.183 +struct MOZ_STACK_CLASS ScrollReflowState {
1.184 + const nsHTMLReflowState& mReflowState;
1.185 + nsBoxLayoutState mBoxState;
1.186 + ScrollbarStyles mStyles;
1.187 + nsMargin mComputedBorder;
1.188 +
1.189 + // === Filled in by ReflowScrolledFrame ===
1.190 + nsOverflowAreas mContentsOverflowAreas;
1.191 + bool mReflowedContentsWithHScrollbar;
1.192 + bool mReflowedContentsWithVScrollbar;
1.193 +
1.194 + // === Filled in when TryLayout succeeds ===
1.195 + // The size of the inside-border area
1.196 + nsSize mInsideBorderSize;
1.197 + // Whether we decided to show the horizontal scrollbar
1.198 + bool mShowHScrollbar;
1.199 + // Whether we decided to show the vertical scrollbar
1.200 + bool mShowVScrollbar;
1.201 +
1.202 + ScrollReflowState(nsIScrollableFrame* aFrame,
1.203 + const nsHTMLReflowState& aState) :
1.204 + mReflowState(aState),
1.205 + // mBoxState is just used for scrollbars so we don't need to
1.206 + // worry about the reflow depth here
1.207 + mBoxState(aState.frame->PresContext(), aState.rendContext, 0),
1.208 + mStyles(aFrame->GetScrollbarStyles()) {
1.209 + }
1.210 +};
1.211 +
1.212 +// XXXldb Can this go away?
1.213 +static nsSize ComputeInsideBorderSize(ScrollReflowState* aState,
1.214 + const nsSize& aDesiredInsideBorderSize)
1.215 +{
1.216 + // aDesiredInsideBorderSize is the frame size; i.e., it includes
1.217 + // borders and padding (but the scrolled child doesn't have
1.218 + // borders). The scrolled child has the same padding as us.
1.219 + nscoord contentWidth = aState->mReflowState.ComputedWidth();
1.220 + if (contentWidth == NS_UNCONSTRAINEDSIZE) {
1.221 + contentWidth = aDesiredInsideBorderSize.width -
1.222 + aState->mReflowState.ComputedPhysicalPadding().LeftRight();
1.223 + }
1.224 + nscoord contentHeight = aState->mReflowState.ComputedHeight();
1.225 + if (contentHeight == NS_UNCONSTRAINEDSIZE) {
1.226 + contentHeight = aDesiredInsideBorderSize.height -
1.227 + aState->mReflowState.ComputedPhysicalPadding().TopBottom();
1.228 + }
1.229 +
1.230 + contentWidth = aState->mReflowState.ApplyMinMaxWidth(contentWidth);
1.231 + contentHeight = aState->mReflowState.ApplyMinMaxHeight(contentHeight);
1.232 + return nsSize(contentWidth + aState->mReflowState.ComputedPhysicalPadding().LeftRight(),
1.233 + contentHeight + aState->mReflowState.ComputedPhysicalPadding().TopBottom());
1.234 +}
1.235 +
1.236 +static void
1.237 +GetScrollbarMetrics(nsBoxLayoutState& aState, nsIFrame* aBox, nsSize* aMin,
1.238 + nsSize* aPref, bool aVertical)
1.239 +{
1.240 + NS_ASSERTION(aState.GetRenderingContext(),
1.241 + "Must have rendering context in layout state for size "
1.242 + "computations");
1.243 +
1.244 + if (aMin) {
1.245 + *aMin = aBox->GetMinSize(aState);
1.246 + nsBox::AddMargin(aBox, *aMin);
1.247 + if (aMin->width < 0) {
1.248 + aMin->width = 0;
1.249 + }
1.250 + if (aMin->height < 0) {
1.251 + aMin->height = 0;
1.252 + }
1.253 + }
1.254 +
1.255 + if (aPref) {
1.256 + *aPref = aBox->GetPrefSize(aState);
1.257 + nsBox::AddMargin(aBox, *aPref);
1.258 + if (aPref->width < 0) {
1.259 + aPref->width = 0;
1.260 + }
1.261 + if (aPref->height < 0) {
1.262 + aPref->height = 0;
1.263 + }
1.264 + }
1.265 +}
1.266 +
1.267 +/**
1.268 + * Assuming that we know the metrics for our wrapped frame and
1.269 + * whether the horizontal and/or vertical scrollbars are present,
1.270 + * compute the resulting layout and return true if the layout is
1.271 + * consistent. If the layout is consistent then we fill in the
1.272 + * computed fields of the ScrollReflowState.
1.273 + *
1.274 + * The layout is consistent when both scrollbars are showing if and only
1.275 + * if they should be showing. A horizontal scrollbar should be showing if all
1.276 + * following conditions are met:
1.277 + * 1) the style is not HIDDEN
1.278 + * 2) our inside-border height is at least the scrollbar height (i.e., the
1.279 + * scrollbar fits vertically)
1.280 + * 3) our scrollport width (the inside-border width minus the width allocated for a
1.281 + * vertical scrollbar, if showing) is at least the scrollbar's min-width
1.282 + * (i.e., the scrollbar fits horizontally)
1.283 + * 4) the style is SCROLL, or the kid's overflow-area XMost is
1.284 + * greater than the scrollport width
1.285 + *
1.286 + * @param aForce if true, then we just assume the layout is consistent.
1.287 + */
1.288 +bool
1.289 +nsHTMLScrollFrame::TryLayout(ScrollReflowState* aState,
1.290 + nsHTMLReflowMetrics* aKidMetrics,
1.291 + bool aAssumeHScroll, bool aAssumeVScroll,
1.292 + bool aForce, nsresult* aResult)
1.293 +{
1.294 + *aResult = NS_OK;
1.295 +
1.296 + if ((aState->mStyles.mVertical == NS_STYLE_OVERFLOW_HIDDEN && aAssumeVScroll) ||
1.297 + (aState->mStyles.mHorizontal == NS_STYLE_OVERFLOW_HIDDEN && aAssumeHScroll)) {
1.298 + NS_ASSERTION(!aForce, "Shouldn't be forcing a hidden scrollbar to show!");
1.299 + return false;
1.300 + }
1.301 +
1.302 + if (aAssumeVScroll != aState->mReflowedContentsWithVScrollbar ||
1.303 + (aAssumeHScroll != aState->mReflowedContentsWithHScrollbar &&
1.304 + ScrolledContentDependsOnHeight(aState))) {
1.305 + nsresult rv = ReflowScrolledFrame(aState, aAssumeHScroll, aAssumeVScroll,
1.306 + aKidMetrics, false);
1.307 + if (NS_FAILED(rv)) {
1.308 + *aResult = rv;
1.309 + return false;
1.310 + }
1.311 + }
1.312 +
1.313 + nsSize vScrollbarMinSize(0, 0);
1.314 + nsSize vScrollbarPrefSize(0, 0);
1.315 + if (mHelper.mVScrollbarBox) {
1.316 + GetScrollbarMetrics(aState->mBoxState, mHelper.mVScrollbarBox,
1.317 + &vScrollbarMinSize,
1.318 + aAssumeVScroll ? &vScrollbarPrefSize : nullptr, true);
1.319 + }
1.320 + nscoord vScrollbarDesiredWidth = aAssumeVScroll ? vScrollbarPrefSize.width : 0;
1.321 + nscoord vScrollbarMinHeight = aAssumeVScroll ? vScrollbarMinSize.height : 0;
1.322 +
1.323 + nsSize hScrollbarMinSize(0, 0);
1.324 + nsSize hScrollbarPrefSize(0, 0);
1.325 + if (mHelper.mHScrollbarBox) {
1.326 + GetScrollbarMetrics(aState->mBoxState, mHelper.mHScrollbarBox,
1.327 + &hScrollbarMinSize,
1.328 + aAssumeHScroll ? &hScrollbarPrefSize : nullptr, false);
1.329 + }
1.330 + nscoord hScrollbarDesiredHeight = aAssumeHScroll ? hScrollbarPrefSize.height : 0;
1.331 + nscoord hScrollbarMinWidth = aAssumeHScroll ? hScrollbarMinSize.width : 0;
1.332 +
1.333 + // First, compute our inside-border size and scrollport size
1.334 + // XXXldb Can we depend more on ComputeSize here?
1.335 + nsSize desiredInsideBorderSize;
1.336 + desiredInsideBorderSize.width = vScrollbarDesiredWidth +
1.337 + std::max(aKidMetrics->Width(), hScrollbarMinWidth);
1.338 + desiredInsideBorderSize.height = hScrollbarDesiredHeight +
1.339 + std::max(aKidMetrics->Height(), vScrollbarMinHeight);
1.340 + aState->mInsideBorderSize =
1.341 + ComputeInsideBorderSize(aState, desiredInsideBorderSize);
1.342 + nsSize scrollPortSize = nsSize(std::max(0, aState->mInsideBorderSize.width - vScrollbarDesiredWidth),
1.343 + std::max(0, aState->mInsideBorderSize.height - hScrollbarDesiredHeight));
1.344 +
1.345 + if (!aForce) {
1.346 + nsRect scrolledRect =
1.347 + mHelper.GetScrolledRectInternal(aState->mContentsOverflowAreas.ScrollableOverflow(),
1.348 + scrollPortSize);
1.349 + nscoord oneDevPixel = aState->mBoxState.PresContext()->DevPixelsToAppUnits(1);
1.350 +
1.351 + // If the style is HIDDEN then we already know that aAssumeHScroll is false
1.352 + if (aState->mStyles.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN) {
1.353 + bool wantHScrollbar =
1.354 + aState->mStyles.mHorizontal == NS_STYLE_OVERFLOW_SCROLL ||
1.355 + scrolledRect.XMost() >= scrollPortSize.width + oneDevPixel ||
1.356 + scrolledRect.x <= -oneDevPixel;
1.357 + if (scrollPortSize.width < hScrollbarMinSize.width)
1.358 + wantHScrollbar = false;
1.359 + if (wantHScrollbar != aAssumeHScroll)
1.360 + return false;
1.361 + }
1.362 +
1.363 + // If the style is HIDDEN then we already know that aAssumeVScroll is false
1.364 + if (aState->mStyles.mVertical != NS_STYLE_OVERFLOW_HIDDEN) {
1.365 + bool wantVScrollbar =
1.366 + aState->mStyles.mVertical == NS_STYLE_OVERFLOW_SCROLL ||
1.367 + scrolledRect.YMost() >= scrollPortSize.height + oneDevPixel ||
1.368 + scrolledRect.y <= -oneDevPixel;
1.369 + if (scrollPortSize.height < vScrollbarMinSize.height)
1.370 + wantVScrollbar = false;
1.371 + if (wantVScrollbar != aAssumeVScroll)
1.372 + return false;
1.373 + }
1.374 + }
1.375 +
1.376 + nscoord vScrollbarActualWidth = aState->mInsideBorderSize.width - scrollPortSize.width;
1.377 +
1.378 + aState->mShowHScrollbar = aAssumeHScroll;
1.379 + aState->mShowVScrollbar = aAssumeVScroll;
1.380 + nsPoint scrollPortOrigin(aState->mComputedBorder.left,
1.381 + aState->mComputedBorder.top);
1.382 + if (!mHelper.IsScrollbarOnRight()) {
1.383 + scrollPortOrigin.x += vScrollbarActualWidth;
1.384 + }
1.385 + mHelper.mScrollPort = nsRect(scrollPortOrigin, scrollPortSize);
1.386 + return true;
1.387 +}
1.388 +
1.389 +bool
1.390 +nsHTMLScrollFrame::ScrolledContentDependsOnHeight(ScrollReflowState* aState)
1.391 +{
1.392 + // Return true if ReflowScrolledFrame is going to do something different
1.393 + // based on the presence of a horizontal scrollbar.
1.394 + return (mHelper.mScrolledFrame->GetStateBits() & NS_FRAME_CONTAINS_RELATIVE_HEIGHT) ||
1.395 + aState->mReflowState.ComputedHeight() != NS_UNCONSTRAINEDSIZE ||
1.396 + aState->mReflowState.ComputedMinHeight() > 0 ||
1.397 + aState->mReflowState.ComputedMaxHeight() != NS_UNCONSTRAINEDSIZE;
1.398 +}
1.399 +
1.400 +nsresult
1.401 +nsHTMLScrollFrame::ReflowScrolledFrame(ScrollReflowState* aState,
1.402 + bool aAssumeHScroll,
1.403 + bool aAssumeVScroll,
1.404 + nsHTMLReflowMetrics* aMetrics,
1.405 + bool aFirstPass)
1.406 +{
1.407 + // these could be NS_UNCONSTRAINEDSIZE ... std::min arithmetic should
1.408 + // be OK
1.409 + const nsMargin& padding = aState->mReflowState.ComputedPhysicalPadding();
1.410 + nscoord availWidth = aState->mReflowState.ComputedWidth() + padding.LeftRight();
1.411 +
1.412 + nscoord computedHeight = aState->mReflowState.ComputedHeight();
1.413 + nscoord computedMinHeight = aState->mReflowState.ComputedMinHeight();
1.414 + nscoord computedMaxHeight = aState->mReflowState.ComputedMaxHeight();
1.415 + if (!ShouldPropagateComputedHeightToScrolledContent()) {
1.416 + computedHeight = NS_UNCONSTRAINEDSIZE;
1.417 + computedMinHeight = 0;
1.418 + computedMaxHeight = NS_UNCONSTRAINEDSIZE;
1.419 + }
1.420 + if (aAssumeHScroll) {
1.421 + nsSize hScrollbarPrefSize;
1.422 + GetScrollbarMetrics(aState->mBoxState, mHelper.mHScrollbarBox,
1.423 + nullptr, &hScrollbarPrefSize, false);
1.424 + if (computedHeight != NS_UNCONSTRAINEDSIZE) {
1.425 + computedHeight = std::max(0, computedHeight - hScrollbarPrefSize.height);
1.426 + }
1.427 + computedMinHeight = std::max(0, computedMinHeight - hScrollbarPrefSize.height);
1.428 + if (computedMaxHeight != NS_UNCONSTRAINEDSIZE) {
1.429 + computedMaxHeight = std::max(0, computedMaxHeight - hScrollbarPrefSize.height);
1.430 + }
1.431 + }
1.432 +
1.433 + if (aAssumeVScroll) {
1.434 + nsSize vScrollbarPrefSize;
1.435 + GetScrollbarMetrics(aState->mBoxState, mHelper.mVScrollbarBox,
1.436 + nullptr, &vScrollbarPrefSize, true);
1.437 + availWidth = std::max(0, availWidth - vScrollbarPrefSize.width);
1.438 + }
1.439 +
1.440 + nsPresContext* presContext = PresContext();
1.441 +
1.442 + // Pass false for aInit so we can pass in the correct padding.
1.443 + nsHTMLReflowState kidReflowState(presContext, aState->mReflowState,
1.444 + mHelper.mScrolledFrame,
1.445 + nsSize(availWidth, NS_UNCONSTRAINEDSIZE),
1.446 + -1, -1, nsHTMLReflowState::CALLER_WILL_INIT);
1.447 + kidReflowState.Init(presContext, -1, -1, nullptr,
1.448 + &padding);
1.449 + kidReflowState.mFlags.mAssumingHScrollbar = aAssumeHScroll;
1.450 + kidReflowState.mFlags.mAssumingVScrollbar = aAssumeVScroll;
1.451 + kidReflowState.SetComputedHeight(computedHeight);
1.452 + kidReflowState.ComputedMinHeight() = computedMinHeight;
1.453 + kidReflowState.ComputedMaxHeight() = computedMaxHeight;
1.454 +
1.455 + // Temporarily set mHasHorizontalScrollbar/mHasVerticalScrollbar to
1.456 + // reflect our assumptions while we reflow the child.
1.457 + bool didHaveHorizontalScrollbar = mHelper.mHasHorizontalScrollbar;
1.458 + bool didHaveVerticalScrollbar = mHelper.mHasVerticalScrollbar;
1.459 + mHelper.mHasHorizontalScrollbar = aAssumeHScroll;
1.460 + mHelper.mHasVerticalScrollbar = aAssumeVScroll;
1.461 +
1.462 + nsReflowStatus status;
1.463 + nsresult rv = ReflowChild(mHelper.mScrolledFrame, presContext, *aMetrics,
1.464 + kidReflowState, 0, 0,
1.465 + NS_FRAME_NO_MOVE_FRAME, status);
1.466 +
1.467 + mHelper.mHasHorizontalScrollbar = didHaveHorizontalScrollbar;
1.468 + mHelper.mHasVerticalScrollbar = didHaveVerticalScrollbar;
1.469 +
1.470 + // Don't resize or position the view (if any) because we're going to resize
1.471 + // it to the correct size anyway in PlaceScrollArea. Allowing it to
1.472 + // resize here would size it to the natural height of the frame,
1.473 + // which will usually be different from the scrollport height;
1.474 + // invalidating the difference will cause unnecessary repainting.
1.475 + FinishReflowChild(mHelper.mScrolledFrame, presContext,
1.476 + *aMetrics, &kidReflowState, 0, 0,
1.477 + NS_FRAME_NO_MOVE_FRAME | NS_FRAME_NO_SIZE_VIEW);
1.478 +
1.479 + // XXX Some frames (e.g., nsObjectFrame, nsFrameFrame, nsTextFrame) don't bother
1.480 + // setting their mOverflowArea. This is wrong because every frame should
1.481 + // always set mOverflowArea. In fact nsObjectFrame and nsFrameFrame don't
1.482 + // support the 'outline' property because of this. Rather than fix the world
1.483 + // right now, just fix up the overflow area if necessary. Note that we don't
1.484 + // check HasOverflowRect() because it could be set even though the
1.485 + // overflow area doesn't include the frame bounds.
1.486 + aMetrics->UnionOverflowAreasWithDesiredBounds();
1.487 +
1.488 + if (MOZ_UNLIKELY(StyleDisplay()->mOverflowClipBox ==
1.489 + NS_STYLE_OVERFLOW_CLIP_BOX_CONTENT_BOX)) {
1.490 + nsOverflowAreas childOverflow;
1.491 + nsLayoutUtils::UnionChildOverflow(mHelper.mScrolledFrame, childOverflow);
1.492 + nsRect childScrollableOverflow = childOverflow.ScrollableOverflow();
1.493 + childScrollableOverflow.Inflate(padding);
1.494 + nsRect contentArea = nsRect(0, 0, availWidth, computedHeight);
1.495 + if (!contentArea.Contains(childScrollableOverflow)) {
1.496 + aMetrics->mOverflowAreas.ScrollableOverflow() = childScrollableOverflow;
1.497 + }
1.498 + }
1.499 +
1.500 + aState->mContentsOverflowAreas = aMetrics->mOverflowAreas;
1.501 + aState->mReflowedContentsWithHScrollbar = aAssumeHScroll;
1.502 + aState->mReflowedContentsWithVScrollbar = aAssumeVScroll;
1.503 +
1.504 + return rv;
1.505 +}
1.506 +
1.507 +bool
1.508 +nsHTMLScrollFrame::GuessHScrollbarNeeded(const ScrollReflowState& aState)
1.509 +{
1.510 + if (aState.mStyles.mHorizontal != NS_STYLE_OVERFLOW_AUTO)
1.511 + // no guessing required
1.512 + return aState.mStyles.mHorizontal == NS_STYLE_OVERFLOW_SCROLL;
1.513 +
1.514 + return mHelper.mHasHorizontalScrollbar;
1.515 +}
1.516 +
1.517 +bool
1.518 +nsHTMLScrollFrame::GuessVScrollbarNeeded(const ScrollReflowState& aState)
1.519 +{
1.520 + if (aState.mStyles.mVertical != NS_STYLE_OVERFLOW_AUTO)
1.521 + // no guessing required
1.522 + return aState.mStyles.mVertical == NS_STYLE_OVERFLOW_SCROLL;
1.523 +
1.524 + // If we've had at least one non-initial reflow, then just assume
1.525 + // the state of the vertical scrollbar will be what we determined
1.526 + // last time.
1.527 + if (mHelper.mHadNonInitialReflow) {
1.528 + return mHelper.mHasVerticalScrollbar;
1.529 + }
1.530 +
1.531 + // If this is the initial reflow, guess false because usually
1.532 + // we have very little content by then.
1.533 + if (InInitialReflow())
1.534 + return false;
1.535 +
1.536 + if (mHelper.mIsRoot) {
1.537 + nsIFrame *f = mHelper.mScrolledFrame->GetFirstPrincipalChild();
1.538 + if (f && f->GetType() == nsGkAtoms::svgOuterSVGFrame &&
1.539 + static_cast<nsSVGOuterSVGFrame*>(f)->VerticalScrollbarNotNeeded()) {
1.540 + // Common SVG case - avoid a bad guess.
1.541 + return false;
1.542 + }
1.543 + // Assume that there will be a scrollbar; it seems to me
1.544 + // that 'most pages' do have a scrollbar, and anyway, it's cheaper
1.545 + // to do an extra reflow for the pages that *don't* need a
1.546 + // scrollbar (because on average they will have less content).
1.547 + return true;
1.548 + }
1.549 +
1.550 + // For non-viewports, just guess that we don't need a scrollbar.
1.551 + // XXX I wonder if statistically this is the right idea; I'm
1.552 + // basically guessing that there are a lot of overflow:auto DIVs
1.553 + // that get their intrinsic size and don't overflow
1.554 + return false;
1.555 +}
1.556 +
1.557 +bool
1.558 +nsHTMLScrollFrame::InInitialReflow() const
1.559 +{
1.560 + // We're in an initial reflow if NS_FRAME_FIRST_REFLOW is set, unless we're a
1.561 + // root scrollframe. In that case we want to skip this clause altogether.
1.562 + // The guess here is that there are lots of overflow:auto divs out there that
1.563 + // end up auto-sizing so they don't overflow, and that the root basically
1.564 + // always needs a scrollbar if it did last time we loaded this page (good
1.565 + // assumption, because our initial reflow is no longer synchronous).
1.566 + return !mHelper.mIsRoot && (GetStateBits() & NS_FRAME_FIRST_REFLOW);
1.567 +}
1.568 +
1.569 +nsresult
1.570 +nsHTMLScrollFrame::ReflowContents(ScrollReflowState* aState,
1.571 + const nsHTMLReflowMetrics& aDesiredSize)
1.572 +{
1.573 + nsHTMLReflowMetrics kidDesiredSize(aDesiredSize.GetWritingMode(), aDesiredSize.mFlags);
1.574 + nsresult rv = ReflowScrolledFrame(aState, GuessHScrollbarNeeded(*aState),
1.575 + GuessVScrollbarNeeded(*aState), &kidDesiredSize, true);
1.576 + NS_ENSURE_SUCCESS(rv, rv);
1.577 +
1.578 + // There's an important special case ... if the child appears to fit
1.579 + // in the inside-border rect (but overflows the scrollport), we
1.580 + // should try laying it out without a vertical scrollbar. It will
1.581 + // usually fit because making the available-width wider will not
1.582 + // normally make the child taller. (The only situation I can think
1.583 + // of is when you have a line containing %-width inline replaced
1.584 + // elements whose percentages sum to more than 100%, so increasing
1.585 + // the available width makes the line break where it was fitting
1.586 + // before.) If we don't treat this case specially, then we will
1.587 + // decide that showing scrollbars is OK because the content
1.588 + // overflows when we're showing scrollbars and we won't try to
1.589 + // remove the vertical scrollbar.
1.590 +
1.591 + // Detecting when we enter this special case is important for when
1.592 + // people design layouts that exactly fit the container "most of the
1.593 + // time".
1.594 +
1.595 + // XXX Is this check really sufficient to catch all the incremental cases
1.596 + // where the ideal case doesn't have a scrollbar?
1.597 + if ((aState->mReflowedContentsWithHScrollbar || aState->mReflowedContentsWithVScrollbar) &&
1.598 + aState->mStyles.mVertical != NS_STYLE_OVERFLOW_SCROLL &&
1.599 + aState->mStyles.mHorizontal != NS_STYLE_OVERFLOW_SCROLL) {
1.600 + nsSize insideBorderSize =
1.601 + ComputeInsideBorderSize(aState,
1.602 + nsSize(kidDesiredSize.Width(), kidDesiredSize.Height()));
1.603 + nsRect scrolledRect =
1.604 + mHelper.GetScrolledRectInternal(kidDesiredSize.ScrollableOverflow(),
1.605 + insideBorderSize);
1.606 + if (nsRect(nsPoint(0, 0), insideBorderSize).Contains(scrolledRect)) {
1.607 + // Let's pretend we had no scrollbars coming in here
1.608 + rv = ReflowScrolledFrame(aState, false, false,
1.609 + &kidDesiredSize, false);
1.610 + NS_ENSURE_SUCCESS(rv, rv);
1.611 + }
1.612 + }
1.613 +
1.614 + // Try vertical scrollbar settings that leave the vertical scrollbar unchanged.
1.615 + // Do this first because changing the vertical scrollbar setting is expensive,
1.616 + // forcing a reflow always.
1.617 +
1.618 + // Try leaving the horizontal scrollbar unchanged first. This will be more
1.619 + // efficient.
1.620 + if (TryLayout(aState, &kidDesiredSize, aState->mReflowedContentsWithHScrollbar,
1.621 + aState->mReflowedContentsWithVScrollbar, false, &rv))
1.622 + return NS_OK;
1.623 + if (TryLayout(aState, &kidDesiredSize, !aState->mReflowedContentsWithHScrollbar,
1.624 + aState->mReflowedContentsWithVScrollbar, false, &rv))
1.625 + return NS_OK;
1.626 +
1.627 + // OK, now try toggling the vertical scrollbar. The performance advantage
1.628 + // of trying the status-quo horizontal scrollbar state
1.629 + // does not exist here (we'll have to reflow due to the vertical scrollbar
1.630 + // change), so always try no horizontal scrollbar first.
1.631 + bool newVScrollbarState = !aState->mReflowedContentsWithVScrollbar;
1.632 + if (TryLayout(aState, &kidDesiredSize, false, newVScrollbarState, false, &rv))
1.633 + return NS_OK;
1.634 + if (TryLayout(aState, &kidDesiredSize, true, newVScrollbarState, false, &rv))
1.635 + return NS_OK;
1.636 +
1.637 + // OK, we're out of ideas. Try again enabling whatever scrollbars we can
1.638 + // enable and force the layout to stick even if it's inconsistent.
1.639 + // This just happens sometimes.
1.640 + TryLayout(aState, &kidDesiredSize,
1.641 + aState->mStyles.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN,
1.642 + aState->mStyles.mVertical != NS_STYLE_OVERFLOW_HIDDEN,
1.643 + true, &rv);
1.644 + return rv;
1.645 +}
1.646 +
1.647 +void
1.648 +nsHTMLScrollFrame::PlaceScrollArea(const ScrollReflowState& aState,
1.649 + const nsPoint& aScrollPosition)
1.650 +{
1.651 + nsIFrame *scrolledFrame = mHelper.mScrolledFrame;
1.652 + // Set the x,y of the scrolled frame to the correct value
1.653 + scrolledFrame->SetPosition(mHelper.mScrollPort.TopLeft() - aScrollPosition);
1.654 +
1.655 + nsRect scrolledArea;
1.656 + // Preserve the width or height of empty rects
1.657 + nsSize portSize = mHelper.mScrollPort.Size();
1.658 + nsRect scrolledRect =
1.659 + mHelper.GetScrolledRectInternal(aState.mContentsOverflowAreas.ScrollableOverflow(),
1.660 + portSize);
1.661 + scrolledArea.UnionRectEdges(scrolledRect,
1.662 + nsRect(nsPoint(0,0), portSize));
1.663 +
1.664 + // Store the new overflow area. Note that this changes where an outline
1.665 + // of the scrolled frame would be painted, but scrolled frames can't have
1.666 + // outlines (the outline would go on this scrollframe instead).
1.667 + // Using FinishAndStoreOverflow is needed so the overflow rect
1.668 + // gets set correctly. It also messes with the overflow rect in the
1.669 + // -moz-hidden-unscrollable case, but scrolled frames can't have
1.670 + // 'overflow' either.
1.671 + // This needs to happen before SyncFrameViewAfterReflow so
1.672 + // HasOverflowRect() will return the correct value.
1.673 + nsOverflowAreas overflow(scrolledArea, scrolledArea);
1.674 + scrolledFrame->FinishAndStoreOverflow(overflow,
1.675 + scrolledFrame->GetSize());
1.676 +
1.677 + // Note that making the view *exactly* the size of the scrolled area
1.678 + // is critical, since the view scrolling code uses the size of the
1.679 + // scrolled view to clamp scroll requests.
1.680 + // Normally the scrolledFrame won't have a view but in some cases it
1.681 + // might create its own.
1.682 + nsContainerFrame::SyncFrameViewAfterReflow(scrolledFrame->PresContext(),
1.683 + scrolledFrame,
1.684 + scrolledFrame->GetView(),
1.685 + scrolledArea,
1.686 + 0);
1.687 +}
1.688 +
1.689 +nscoord
1.690 +nsHTMLScrollFrame::GetIntrinsicVScrollbarWidth(nsRenderingContext *aRenderingContext)
1.691 +{
1.692 + ScrollbarStyles ss = GetScrollbarStyles();
1.693 + if (ss.mVertical != NS_STYLE_OVERFLOW_SCROLL || !mHelper.mVScrollbarBox)
1.694 + return 0;
1.695 +
1.696 + // Don't need to worry about reflow depth here since it's
1.697 + // just for scrollbars
1.698 + nsBoxLayoutState bls(PresContext(), aRenderingContext, 0);
1.699 + nsSize vScrollbarPrefSize(0, 0);
1.700 + GetScrollbarMetrics(bls, mHelper.mVScrollbarBox,
1.701 + nullptr, &vScrollbarPrefSize, true);
1.702 + return vScrollbarPrefSize.width;
1.703 +}
1.704 +
1.705 +/* virtual */ nscoord
1.706 +nsHTMLScrollFrame::GetMinWidth(nsRenderingContext *aRenderingContext)
1.707 +{
1.708 + nscoord result = mHelper.mScrolledFrame->GetMinWidth(aRenderingContext);
1.709 + DISPLAY_MIN_WIDTH(this, result);
1.710 + return result + GetIntrinsicVScrollbarWidth(aRenderingContext);
1.711 +}
1.712 +
1.713 +/* virtual */ nscoord
1.714 +nsHTMLScrollFrame::GetPrefWidth(nsRenderingContext *aRenderingContext)
1.715 +{
1.716 + nscoord result = mHelper.mScrolledFrame->GetPrefWidth(aRenderingContext);
1.717 + DISPLAY_PREF_WIDTH(this, result);
1.718 + return NSCoordSaturatingAdd(result, GetIntrinsicVScrollbarWidth(aRenderingContext));
1.719 +}
1.720 +
1.721 +nsresult
1.722 +nsHTMLScrollFrame::GetPadding(nsMargin& aMargin)
1.723 +{
1.724 + // Our padding hangs out on the inside of the scrollframe, but XUL doesn't
1.725 + // reaize that. If we're stuck inside a XUL box, we need to claim no
1.726 + // padding.
1.727 + // @see also nsXULScrollFrame::GetPadding.
1.728 + aMargin.SizeTo(0,0,0,0);
1.729 + return NS_OK;
1.730 +}
1.731 +
1.732 +bool
1.733 +nsHTMLScrollFrame::IsCollapsed()
1.734 +{
1.735 + // We're never collapsed in the box sense.
1.736 + return false;
1.737 +}
1.738 +
1.739 +// Return the <browser> if the scrollframe is for the root frame directly
1.740 +// inside a <browser>.
1.741 +static nsIContent*
1.742 +GetBrowserRoot(nsIContent* aContent)
1.743 +{
1.744 + if (aContent) {
1.745 + nsIDocument* doc = aContent->GetCurrentDoc();
1.746 + nsPIDOMWindow* win = doc->GetWindow();
1.747 + if (win) {
1.748 + nsCOMPtr<nsIContent> frameContent =
1.749 + do_QueryInterface(win->GetFrameElementInternal());
1.750 + if (frameContent &&
1.751 + frameContent->NodeInfo()->Equals(nsGkAtoms::browser, kNameSpaceID_XUL))
1.752 + return frameContent;
1.753 + }
1.754 + }
1.755 +
1.756 + return nullptr;
1.757 +}
1.758 +
1.759 +nsresult
1.760 +nsHTMLScrollFrame::Reflow(nsPresContext* aPresContext,
1.761 + nsHTMLReflowMetrics& aDesiredSize,
1.762 + const nsHTMLReflowState& aReflowState,
1.763 + nsReflowStatus& aStatus)
1.764 +{
1.765 + DO_GLOBAL_REFLOW_COUNT("nsHTMLScrollFrame");
1.766 + DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
1.767 +
1.768 + mHelper.HandleScrollbarStyleSwitching();
1.769 +
1.770 + ScrollReflowState state(this, aReflowState);
1.771 + // sanity check: ensure that if we have no scrollbar, we treat it
1.772 + // as hidden.
1.773 + if (!mHelper.mVScrollbarBox || mHelper.mNeverHasVerticalScrollbar)
1.774 + state.mStyles.mVertical = NS_STYLE_OVERFLOW_HIDDEN;
1.775 + if (!mHelper.mHScrollbarBox || mHelper.mNeverHasHorizontalScrollbar)
1.776 + state.mStyles.mHorizontal = NS_STYLE_OVERFLOW_HIDDEN;
1.777 +
1.778 + //------------ Handle Incremental Reflow -----------------
1.779 + bool reflowHScrollbar = true;
1.780 + bool reflowVScrollbar = true;
1.781 + bool reflowScrollCorner = true;
1.782 + if (!aReflowState.ShouldReflowAllKids()) {
1.783 + #define NEEDS_REFLOW(frame_) \
1.784 + ((frame_) && NS_SUBTREE_DIRTY(frame_))
1.785 +
1.786 + reflowHScrollbar = NEEDS_REFLOW(mHelper.mHScrollbarBox);
1.787 + reflowVScrollbar = NEEDS_REFLOW(mHelper.mVScrollbarBox);
1.788 + reflowScrollCorner = NEEDS_REFLOW(mHelper.mScrollCornerBox) ||
1.789 + NEEDS_REFLOW(mHelper.mResizerBox);
1.790 +
1.791 + #undef NEEDS_REFLOW
1.792 + }
1.793 +
1.794 + if (mHelper.mIsRoot) {
1.795 + mHelper.mCollapsedResizer = true;
1.796 +
1.797 + nsIContent* browserRoot = GetBrowserRoot(mContent);
1.798 + if (browserRoot) {
1.799 + bool showResizer = browserRoot->HasAttr(kNameSpaceID_None, nsGkAtoms::showresizer);
1.800 + reflowScrollCorner = showResizer == mHelper.mCollapsedResizer;
1.801 + mHelper.mCollapsedResizer = !showResizer;
1.802 + }
1.803 + }
1.804 +
1.805 + nsRect oldScrollAreaBounds = mHelper.mScrollPort;
1.806 + nsRect oldScrolledAreaBounds =
1.807 + mHelper.mScrolledFrame->GetScrollableOverflowRectRelativeToParent();
1.808 + nsPoint oldScrollPosition = mHelper.GetScrollPosition();
1.809 +
1.810 + state.mComputedBorder = aReflowState.ComputedPhysicalBorderPadding() -
1.811 + aReflowState.ComputedPhysicalPadding();
1.812 +
1.813 + nsresult rv = ReflowContents(&state, aDesiredSize);
1.814 + if (NS_FAILED(rv))
1.815 + return rv;
1.816 +
1.817 + // Restore the old scroll position, for now, even if that's not valid anymore
1.818 + // because we changed size. We'll fix it up in a post-reflow callback, because
1.819 + // our current size may only be temporary (e.g. we're compute XUL desired sizes).
1.820 + PlaceScrollArea(state, oldScrollPosition);
1.821 + if (!mHelper.mPostedReflowCallback) {
1.822 + // Make sure we'll try scrolling to restored position
1.823 + PresContext()->PresShell()->PostReflowCallback(&mHelper);
1.824 + mHelper.mPostedReflowCallback = true;
1.825 + }
1.826 +
1.827 + bool didHaveHScrollbar = mHelper.mHasHorizontalScrollbar;
1.828 + bool didHaveVScrollbar = mHelper.mHasVerticalScrollbar;
1.829 + mHelper.mHasHorizontalScrollbar = state.mShowHScrollbar;
1.830 + mHelper.mHasVerticalScrollbar = state.mShowVScrollbar;
1.831 + nsRect newScrollAreaBounds = mHelper.mScrollPort;
1.832 + nsRect newScrolledAreaBounds =
1.833 + mHelper.mScrolledFrame->GetScrollableOverflowRectRelativeToParent();
1.834 + if (mHelper.mSkippedScrollbarLayout ||
1.835 + reflowHScrollbar || reflowVScrollbar || reflowScrollCorner ||
1.836 + (GetStateBits() & NS_FRAME_IS_DIRTY) ||
1.837 + didHaveHScrollbar != state.mShowHScrollbar ||
1.838 + didHaveVScrollbar != state.mShowVScrollbar ||
1.839 + !oldScrollAreaBounds.IsEqualEdges(newScrollAreaBounds) ||
1.840 + !oldScrolledAreaBounds.IsEqualEdges(newScrolledAreaBounds)) {
1.841 + if (!mHelper.mSupppressScrollbarUpdate) {
1.842 + mHelper.mSkippedScrollbarLayout = false;
1.843 + mHelper.SetScrollbarVisibility(mHelper.mHScrollbarBox, state.mShowHScrollbar);
1.844 + mHelper.SetScrollbarVisibility(mHelper.mVScrollbarBox, state.mShowVScrollbar);
1.845 + // place and reflow scrollbars
1.846 + nsRect insideBorderArea =
1.847 + nsRect(nsPoint(state.mComputedBorder.left, state.mComputedBorder.top),
1.848 + state.mInsideBorderSize);
1.849 + mHelper.LayoutScrollbars(state.mBoxState, insideBorderArea,
1.850 + oldScrollAreaBounds);
1.851 + } else {
1.852 + mHelper.mSkippedScrollbarLayout = true;
1.853 + }
1.854 + }
1.855 +
1.856 + aDesiredSize.Width() = state.mInsideBorderSize.width +
1.857 + state.mComputedBorder.LeftRight();
1.858 + aDesiredSize.Height() = state.mInsideBorderSize.height +
1.859 + state.mComputedBorder.TopBottom();
1.860 +
1.861 + aDesiredSize.SetOverflowAreasToDesiredBounds();
1.862 + if (mHelper.IsIgnoringViewportClipping()) {
1.863 + aDesiredSize.mOverflowAreas.UnionWith(
1.864 + state.mContentsOverflowAreas + mHelper.mScrolledFrame->GetPosition());
1.865 + }
1.866 +
1.867 + mHelper.UpdateSticky();
1.868 + FinishReflowWithAbsoluteFrames(aPresContext, aDesiredSize, aReflowState, aStatus);
1.869 +
1.870 + if (!InInitialReflow() && !mHelper.mHadNonInitialReflow) {
1.871 + mHelper.mHadNonInitialReflow = true;
1.872 + }
1.873 +
1.874 + if (mHelper.mIsRoot && !oldScrolledAreaBounds.IsEqualEdges(newScrolledAreaBounds)) {
1.875 + mHelper.PostScrolledAreaEvent();
1.876 + }
1.877 +
1.878 + aStatus = NS_FRAME_COMPLETE;
1.879 + NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
1.880 + mHelper.PostOverflowEvent();
1.881 + return rv;
1.882 +}
1.883 +
1.884 +
1.885 +////////////////////////////////////////////////////////////////////////////////
1.886 +
1.887 +#ifdef DEBUG_FRAME_DUMP
1.888 +nsresult
1.889 +nsHTMLScrollFrame::GetFrameName(nsAString& aResult) const
1.890 +{
1.891 + return MakeFrameName(NS_LITERAL_STRING("HTMLScroll"), aResult);
1.892 +}
1.893 +#endif
1.894 +
1.895 +#ifdef ACCESSIBILITY
1.896 +a11y::AccType
1.897 +nsHTMLScrollFrame::AccessibleType()
1.898 +{
1.899 + // Create an accessible regardless of focusable state because the state can be
1.900 + // changed during frame life cycle without any notifications to accessibility.
1.901 + if (mContent->IsRootOfNativeAnonymousSubtree() ||
1.902 + GetScrollbarStyles() ==
1.903 + ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_HIDDEN) ) {
1.904 + return a11y::eNoType;
1.905 + }
1.906 +
1.907 + return a11y::eHyperTextType;
1.908 +}
1.909 +#endif
1.910 +
1.911 +NS_QUERYFRAME_HEAD(nsHTMLScrollFrame)
1.912 + NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
1.913 + NS_QUERYFRAME_ENTRY(nsIScrollbarOwner)
1.914 + NS_QUERYFRAME_ENTRY(nsIScrollableFrame)
1.915 + NS_QUERYFRAME_ENTRY(nsIStatefulFrame)
1.916 +NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
1.917 +
1.918 +//----------nsXULScrollFrame-------------------------------------------
1.919 +
1.920 +nsIFrame*
1.921 +NS_NewXULScrollFrame(nsIPresShell* aPresShell, nsStyleContext* aContext,
1.922 + bool aIsRoot, bool aClipAllDescendants)
1.923 +{
1.924 + return new (aPresShell) nsXULScrollFrame(aPresShell, aContext, aIsRoot,
1.925 + aClipAllDescendants);
1.926 +}
1.927 +
1.928 +NS_IMPL_FRAMEARENA_HELPERS(nsXULScrollFrame)
1.929 +
1.930 +nsXULScrollFrame::nsXULScrollFrame(nsIPresShell* aShell, nsStyleContext* aContext,
1.931 + bool aIsRoot, bool aClipAllDescendants)
1.932 + : nsBoxFrame(aShell, aContext, aIsRoot),
1.933 + mHelper(ALLOW_THIS_IN_INITIALIZER_LIST(this), aIsRoot)
1.934 +{
1.935 + SetLayoutManager(nullptr);
1.936 + mHelper.mClipAllDescendants = aClipAllDescendants;
1.937 +}
1.938 +
1.939 +void
1.940 +nsXULScrollFrame::ScrollbarActivityStarted() const
1.941 +{
1.942 + if (mHelper.mScrollbarActivity) {
1.943 + mHelper.mScrollbarActivity->ActivityStarted();
1.944 + }
1.945 +}
1.946 +
1.947 +void
1.948 +nsXULScrollFrame::ScrollbarActivityStopped() const
1.949 +{
1.950 + if (mHelper.mScrollbarActivity) {
1.951 + mHelper.mScrollbarActivity->ActivityStopped();
1.952 + }
1.953 +}
1.954 +
1.955 +nsMargin
1.956 +ScrollFrameHelper::GetDesiredScrollbarSizes(nsBoxLayoutState* aState)
1.957 +{
1.958 + NS_ASSERTION(aState && aState->GetRenderingContext(),
1.959 + "Must have rendering context in layout state for size "
1.960 + "computations");
1.961 +
1.962 + nsMargin result(0, 0, 0, 0);
1.963 +
1.964 + if (mVScrollbarBox) {
1.965 + nsSize size = mVScrollbarBox->GetPrefSize(*aState);
1.966 + nsBox::AddMargin(mVScrollbarBox, size);
1.967 + if (IsScrollbarOnRight())
1.968 + result.left = size.width;
1.969 + else
1.970 + result.right = size.width;
1.971 + }
1.972 +
1.973 + if (mHScrollbarBox) {
1.974 + nsSize size = mHScrollbarBox->GetPrefSize(*aState);
1.975 + nsBox::AddMargin(mHScrollbarBox, size);
1.976 + // We don't currently support any scripts that would require a scrollbar
1.977 + // at the top. (Are there any?)
1.978 + result.bottom = size.height;
1.979 + }
1.980 +
1.981 + return result;
1.982 +}
1.983 +
1.984 +nscoord
1.985 +ScrollFrameHelper::GetNondisappearingScrollbarWidth(nsBoxLayoutState* aState)
1.986 +{
1.987 + NS_ASSERTION(aState && aState->GetRenderingContext(),
1.988 + "Must have rendering context in layout state for size "
1.989 + "computations");
1.990 +
1.991 + if (LookAndFeel::GetInt(LookAndFeel::eIntID_UseOverlayScrollbars) != 0) {
1.992 + // We're using overlay scrollbars, so we need to get the width that
1.993 + // non-disappearing scrollbars would have.
1.994 + nsITheme* theme = aState->PresContext()->GetTheme();
1.995 + if (theme &&
1.996 + theme->ThemeSupportsWidget(aState->PresContext(),
1.997 + mVScrollbarBox,
1.998 + NS_THEME_SCROLLBAR_NON_DISAPPEARING)) {
1.999 + nsIntSize size;
1.1000 + nsRenderingContext* rendContext = aState->GetRenderingContext();
1.1001 + if (rendContext) {
1.1002 + bool canOverride = true;
1.1003 + theme->GetMinimumWidgetSize(rendContext,
1.1004 + mVScrollbarBox,
1.1005 + NS_THEME_SCROLLBAR_NON_DISAPPEARING,
1.1006 + &size,
1.1007 + &canOverride);
1.1008 + if (size.width) {
1.1009 + return aState->PresContext()->DevPixelsToAppUnits(size.width);
1.1010 + }
1.1011 + }
1.1012 + }
1.1013 + }
1.1014 +
1.1015 + return GetDesiredScrollbarSizes(aState).LeftRight();
1.1016 +}
1.1017 +
1.1018 +void
1.1019 +ScrollFrameHelper::HandleScrollbarStyleSwitching()
1.1020 +{
1.1021 + // Check if we switched between scrollbar styles.
1.1022 + if (mScrollbarActivity &&
1.1023 + LookAndFeel::GetInt(LookAndFeel::eIntID_UseOverlayScrollbars) == 0) {
1.1024 + mScrollbarActivity->Destroy();
1.1025 + mScrollbarActivity = nullptr;
1.1026 + mOuter->PresContext()->ThemeChanged();
1.1027 + }
1.1028 + else if (!mScrollbarActivity &&
1.1029 + LookAndFeel::GetInt(LookAndFeel::eIntID_UseOverlayScrollbars) != 0) {
1.1030 + mScrollbarActivity = new ScrollbarActivity(do_QueryFrame(mOuter));
1.1031 + mOuter->PresContext()->ThemeChanged();
1.1032 + }
1.1033 +}
1.1034 +
1.1035 +static bool IsFocused(nsIContent* aContent)
1.1036 +{
1.1037 + // Some content elements, like the GetContent() of a scroll frame
1.1038 + // for a text input field, are inside anonymous subtrees, but the focus
1.1039 + // manager always reports a non-anonymous element as the focused one, so
1.1040 + // walk up the tree until we reach a non-anonymous element.
1.1041 + while (aContent && aContent->IsInAnonymousSubtree()) {
1.1042 + aContent = aContent->GetParent();
1.1043 + }
1.1044 +
1.1045 + return aContent ? nsContentUtils::IsFocusedContent(aContent) : false;
1.1046 +}
1.1047 +
1.1048 +bool
1.1049 +ScrollFrameHelper::WantAsyncScroll() const
1.1050 +{
1.1051 + nsRect scrollRange = GetScrollRange();
1.1052 + ScrollbarStyles styles = GetScrollbarStylesFromFrame();
1.1053 + bool isFocused = IsFocused(mOuter->GetContent());
1.1054 + bool isVScrollable = (scrollRange.height > 0)
1.1055 + && (styles.mVertical != NS_STYLE_OVERFLOW_HIDDEN);
1.1056 + bool isHScrollable = (scrollRange.width > 0)
1.1057 + && (styles.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN);
1.1058 + // The check for scroll bars was added in bug 825692 to prevent layerization
1.1059 + // of text inputs for performance reasons. However, if a text input is
1.1060 + // focused we want to layerize it so we can async scroll it (bug 946408).
1.1061 + bool isVAsyncScrollable = isVScrollable && (mVScrollbarBox || isFocused);
1.1062 + bool isHAsyncScrollable = isHScrollable && (mHScrollbarBox || isFocused);
1.1063 + return isVAsyncScrollable || isHAsyncScrollable;
1.1064 +}
1.1065 +
1.1066 +nsresult
1.1067 +nsXULScrollFrame::CreateAnonymousContent(nsTArray<ContentInfo>& aElements)
1.1068 +{
1.1069 + return mHelper.CreateAnonymousContent(aElements);
1.1070 +}
1.1071 +
1.1072 +void
1.1073 +nsXULScrollFrame::AppendAnonymousContentTo(nsBaseContentList& aElements,
1.1074 + uint32_t aFilter)
1.1075 +{
1.1076 + mHelper.AppendAnonymousContentTo(aElements, aFilter);
1.1077 +}
1.1078 +
1.1079 +void
1.1080 +nsXULScrollFrame::DestroyFrom(nsIFrame* aDestructRoot)
1.1081 +{
1.1082 + mHelper.Destroy();
1.1083 + nsBoxFrame::DestroyFrom(aDestructRoot);
1.1084 +}
1.1085 +
1.1086 +nsresult
1.1087 +nsXULScrollFrame::SetInitialChildList(ChildListID aListID,
1.1088 + nsFrameList& aChildList)
1.1089 +{
1.1090 + nsresult rv = nsBoxFrame::SetInitialChildList(aListID, aChildList);
1.1091 + mHelper.ReloadChildFrames();
1.1092 + return rv;
1.1093 +}
1.1094 +
1.1095 +
1.1096 +nsresult
1.1097 +nsXULScrollFrame::AppendFrames(ChildListID aListID,
1.1098 + nsFrameList& aFrameList)
1.1099 +{
1.1100 + nsresult rv = nsBoxFrame::AppendFrames(aListID, aFrameList);
1.1101 + mHelper.ReloadChildFrames();
1.1102 + return rv;
1.1103 +}
1.1104 +
1.1105 +nsresult
1.1106 +nsXULScrollFrame::InsertFrames(ChildListID aListID,
1.1107 + nsIFrame* aPrevFrame,
1.1108 + nsFrameList& aFrameList)
1.1109 +{
1.1110 + nsresult rv = nsBoxFrame::InsertFrames(aListID, aPrevFrame, aFrameList);
1.1111 + mHelper.ReloadChildFrames();
1.1112 + return rv;
1.1113 +}
1.1114 +
1.1115 +nsresult
1.1116 +nsXULScrollFrame::RemoveFrame(ChildListID aListID,
1.1117 + nsIFrame* aOldFrame)
1.1118 +{
1.1119 + nsresult rv = nsBoxFrame::RemoveFrame(aListID, aOldFrame);
1.1120 + mHelper.ReloadChildFrames();
1.1121 + return rv;
1.1122 +}
1.1123 +
1.1124 +nsSplittableType
1.1125 +nsXULScrollFrame::GetSplittableType() const
1.1126 +{
1.1127 + return NS_FRAME_NOT_SPLITTABLE;
1.1128 +}
1.1129 +
1.1130 +nsresult
1.1131 +nsXULScrollFrame::GetPadding(nsMargin& aMargin)
1.1132 +{
1.1133 + aMargin.SizeTo(0,0,0,0);
1.1134 + return NS_OK;
1.1135 +}
1.1136 +
1.1137 +nsIAtom*
1.1138 +nsXULScrollFrame::GetType() const
1.1139 +{
1.1140 + return nsGkAtoms::scrollFrame;
1.1141 +}
1.1142 +
1.1143 +nscoord
1.1144 +nsXULScrollFrame::GetBoxAscent(nsBoxLayoutState& aState)
1.1145 +{
1.1146 + if (!mHelper.mScrolledFrame)
1.1147 + return 0;
1.1148 +
1.1149 + nscoord ascent = mHelper.mScrolledFrame->GetBoxAscent(aState);
1.1150 + nsMargin m(0,0,0,0);
1.1151 + GetBorderAndPadding(m);
1.1152 + ascent += m.top;
1.1153 + GetMargin(m);
1.1154 + ascent += m.top;
1.1155 +
1.1156 + return ascent;
1.1157 +}
1.1158 +
1.1159 +nsSize
1.1160 +nsXULScrollFrame::GetPrefSize(nsBoxLayoutState& aState)
1.1161 +{
1.1162 +#ifdef DEBUG_LAYOUT
1.1163 + PropagateDebug(aState);
1.1164 +#endif
1.1165 +
1.1166 + nsSize pref = mHelper.mScrolledFrame->GetPrefSize(aState);
1.1167 +
1.1168 + ScrollbarStyles styles = GetScrollbarStyles();
1.1169 +
1.1170 + // scrolled frames don't have their own margins
1.1171 +
1.1172 + if (mHelper.mVScrollbarBox &&
1.1173 + styles.mVertical == NS_STYLE_OVERFLOW_SCROLL) {
1.1174 + nsSize vSize = mHelper.mVScrollbarBox->GetPrefSize(aState);
1.1175 + nsBox::AddMargin(mHelper.mVScrollbarBox, vSize);
1.1176 + pref.width += vSize.width;
1.1177 + }
1.1178 +
1.1179 + if (mHelper.mHScrollbarBox &&
1.1180 + styles.mHorizontal == NS_STYLE_OVERFLOW_SCROLL) {
1.1181 + nsSize hSize = mHelper.mHScrollbarBox->GetPrefSize(aState);
1.1182 + nsBox::AddMargin(mHelper.mHScrollbarBox, hSize);
1.1183 + pref.height += hSize.height;
1.1184 + }
1.1185 +
1.1186 + AddBorderAndPadding(pref);
1.1187 + bool widthSet, heightSet;
1.1188 + nsIFrame::AddCSSPrefSize(this, pref, widthSet, heightSet);
1.1189 + return pref;
1.1190 +}
1.1191 +
1.1192 +nsSize
1.1193 +nsXULScrollFrame::GetMinSize(nsBoxLayoutState& aState)
1.1194 +{
1.1195 +#ifdef DEBUG_LAYOUT
1.1196 + PropagateDebug(aState);
1.1197 +#endif
1.1198 +
1.1199 + nsSize min = mHelper.mScrolledFrame->GetMinSizeForScrollArea(aState);
1.1200 +
1.1201 + ScrollbarStyles styles = GetScrollbarStyles();
1.1202 +
1.1203 + if (mHelper.mVScrollbarBox &&
1.1204 + styles.mVertical == NS_STYLE_OVERFLOW_SCROLL) {
1.1205 + nsSize vSize = mHelper.mVScrollbarBox->GetMinSize(aState);
1.1206 + AddMargin(mHelper.mVScrollbarBox, vSize);
1.1207 + min.width += vSize.width;
1.1208 + if (min.height < vSize.height)
1.1209 + min.height = vSize.height;
1.1210 + }
1.1211 +
1.1212 + if (mHelper.mHScrollbarBox &&
1.1213 + styles.mHorizontal == NS_STYLE_OVERFLOW_SCROLL) {
1.1214 + nsSize hSize = mHelper.mHScrollbarBox->GetMinSize(aState);
1.1215 + AddMargin(mHelper.mHScrollbarBox, hSize);
1.1216 + min.height += hSize.height;
1.1217 + if (min.width < hSize.width)
1.1218 + min.width = hSize.width;
1.1219 + }
1.1220 +
1.1221 + AddBorderAndPadding(min);
1.1222 + bool widthSet, heightSet;
1.1223 + nsIFrame::AddCSSMinSize(aState, this, min, widthSet, heightSet);
1.1224 + return min;
1.1225 +}
1.1226 +
1.1227 +nsSize
1.1228 +nsXULScrollFrame::GetMaxSize(nsBoxLayoutState& aState)
1.1229 +{
1.1230 +#ifdef DEBUG_LAYOUT
1.1231 + PropagateDebug(aState);
1.1232 +#endif
1.1233 +
1.1234 + nsSize maxSize(NS_INTRINSICSIZE, NS_INTRINSICSIZE);
1.1235 +
1.1236 + AddBorderAndPadding(maxSize);
1.1237 + bool widthSet, heightSet;
1.1238 + nsIFrame::AddCSSMaxSize(this, maxSize, widthSet, heightSet);
1.1239 + return maxSize;
1.1240 +}
1.1241 +
1.1242 +#ifdef DEBUG_FRAME_DUMP
1.1243 +nsresult
1.1244 +nsXULScrollFrame::GetFrameName(nsAString& aResult) const
1.1245 +{
1.1246 + return MakeFrameName(NS_LITERAL_STRING("XULScroll"), aResult);
1.1247 +}
1.1248 +#endif
1.1249 +
1.1250 +NS_IMETHODIMP
1.1251 +nsXULScrollFrame::DoLayout(nsBoxLayoutState& aState)
1.1252 +{
1.1253 + uint32_t flags = aState.LayoutFlags();
1.1254 + nsresult rv = Layout(aState);
1.1255 + aState.SetLayoutFlags(flags);
1.1256 +
1.1257 + nsBox::DoLayout(aState);
1.1258 + return rv;
1.1259 +}
1.1260 +
1.1261 +NS_QUERYFRAME_HEAD(nsXULScrollFrame)
1.1262 + NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
1.1263 + NS_QUERYFRAME_ENTRY(nsIScrollbarOwner)
1.1264 + NS_QUERYFRAME_ENTRY(nsIScrollableFrame)
1.1265 + NS_QUERYFRAME_ENTRY(nsIStatefulFrame)
1.1266 +NS_QUERYFRAME_TAIL_INHERITING(nsBoxFrame)
1.1267 +
1.1268 +//-------------------- Helper ----------------------
1.1269 +
1.1270 +#define SMOOTH_SCROLL_PREF_NAME "general.smoothScroll"
1.1271 +
1.1272 +const double kCurrentVelocityWeighting = 0.25;
1.1273 +const double kStopDecelerationWeighting = 0.4;
1.1274 +
1.1275 +// AsyncScroll has ref counting.
1.1276 +class ScrollFrameHelper::AsyncScroll MOZ_FINAL : public nsARefreshObserver {
1.1277 +public:
1.1278 + typedef mozilla::TimeStamp TimeStamp;
1.1279 + typedef mozilla::TimeDuration TimeDuration;
1.1280 +
1.1281 + AsyncScroll(nsPoint aStartPos)
1.1282 + : mIsFirstIteration(true)
1.1283 + , mStartPos(aStartPos)
1.1284 + , mCallee(nullptr)
1.1285 + {}
1.1286 +
1.1287 +private:
1.1288 + // Private destructor, to discourage deletion outside of Release():
1.1289 + ~AsyncScroll() {
1.1290 + RemoveObserver();
1.1291 + }
1.1292 +
1.1293 +public:
1.1294 + nsPoint PositionAt(TimeStamp aTime);
1.1295 + nsSize VelocityAt(TimeStamp aTime); // In nscoords per second
1.1296 +
1.1297 + void InitSmoothScroll(TimeStamp aTime, nsPoint aDestination,
1.1298 + nsIAtom *aOrigin, const nsRect& aRange);
1.1299 + void Init(const nsRect& aRange) {
1.1300 + mRange = aRange;
1.1301 + }
1.1302 +
1.1303 + bool IsFinished(TimeStamp aTime) {
1.1304 + return aTime > mStartTime + mDuration; // XXX or if we've hit the wall
1.1305 + }
1.1306 +
1.1307 + TimeStamp mStartTime;
1.1308 +
1.1309 + // mPrevEventTime holds previous 3 timestamps for intervals averaging (to
1.1310 + // reduce duration fluctuations). When AsyncScroll is constructed and no
1.1311 + // previous timestamps are available (indicated with mIsFirstIteration),
1.1312 + // initialize mPrevEventTime using imaginary previous timestamps with maximum
1.1313 + // relevant intervals between them.
1.1314 + TimeStamp mPrevEventTime[3];
1.1315 + bool mIsFirstIteration;
1.1316 +
1.1317 + // Cached Preferences values to avoid re-reading them when extending an existing
1.1318 + // animation for the same event origin (can be as frequent as every 10(!)ms for
1.1319 + // a quick roll of the mouse wheel).
1.1320 + // These values are minimum and maximum animation duration per event origin,
1.1321 + // and a global ratio which defines how longer is the animation's duration
1.1322 + // compared to the average recent events intervals (such that for a relatively
1.1323 + // consistent events rate, the next event arrives before current animation ends)
1.1324 + nsCOMPtr<nsIAtom> mOrigin;
1.1325 + int32_t mOriginMinMS;
1.1326 + int32_t mOriginMaxMS;
1.1327 + double mIntervalRatio;
1.1328 +
1.1329 + TimeDuration mDuration;
1.1330 + nsPoint mStartPos;
1.1331 + nsPoint mDestination;
1.1332 + // Allowed destination positions around mDestination
1.1333 + nsRect mRange;
1.1334 + nsSMILKeySpline mTimingFunctionX;
1.1335 + nsSMILKeySpline mTimingFunctionY;
1.1336 + bool mIsSmoothScroll;
1.1337 +
1.1338 +protected:
1.1339 + double ProgressAt(TimeStamp aTime) {
1.1340 + return clamped((aTime - mStartTime) / mDuration, 0.0, 1.0);
1.1341 + }
1.1342 +
1.1343 + nscoord VelocityComponent(double aTimeProgress,
1.1344 + nsSMILKeySpline& aTimingFunction,
1.1345 + nscoord aStart, nscoord aDestination);
1.1346 +
1.1347 + // Initializes the timing function in such a way that the current velocity is
1.1348 + // preserved.
1.1349 + void InitTimingFunction(nsSMILKeySpline& aTimingFunction,
1.1350 + nscoord aCurrentPos, nscoord aCurrentVelocity,
1.1351 + nscoord aDestination);
1.1352 +
1.1353 + TimeDuration CalcDurationForEventTime(TimeStamp aTime, nsIAtom *aOrigin);
1.1354 +
1.1355 +// The next section is observer/callback management
1.1356 +// Bodies of WillRefresh and RefreshDriver contain ScrollFrameHelper specific code.
1.1357 +public:
1.1358 + NS_INLINE_DECL_REFCOUNTING(AsyncScroll)
1.1359 +
1.1360 + /*
1.1361 + * Set a refresh observer for smooth scroll iterations (and start observing).
1.1362 + * Should be used at most once during the lifetime of this object.
1.1363 + * Return value: true on success, false otherwise.
1.1364 + */
1.1365 + bool SetRefreshObserver(ScrollFrameHelper *aCallee) {
1.1366 + NS_ASSERTION(aCallee && !mCallee, "AsyncScroll::SetRefreshObserver - Invalid usage.");
1.1367 +
1.1368 + if (!RefreshDriver(aCallee)->AddRefreshObserver(this, Flush_Style)) {
1.1369 + return false;
1.1370 + }
1.1371 +
1.1372 + mCallee = aCallee;
1.1373 + return true;
1.1374 + }
1.1375 +
1.1376 + virtual void WillRefresh(mozilla::TimeStamp aTime) MOZ_OVERRIDE {
1.1377 + // The callback may release "this".
1.1378 + // We don't access members after returning, so no need for KungFuDeathGrip.
1.1379 + ScrollFrameHelper::AsyncScrollCallback(mCallee, aTime);
1.1380 + }
1.1381 +
1.1382 +private:
1.1383 + ScrollFrameHelper *mCallee;
1.1384 +
1.1385 + nsRefreshDriver* RefreshDriver(ScrollFrameHelper* aCallee) {
1.1386 + return aCallee->mOuter->PresContext()->RefreshDriver();
1.1387 + }
1.1388 +
1.1389 + /*
1.1390 + * The refresh driver doesn't hold a reference to its observers,
1.1391 + * so releasing this object can (and is) used to remove the observer on DTOR.
1.1392 + * Currently, this object is released once the scrolling ends.
1.1393 + */
1.1394 + void RemoveObserver() {
1.1395 + if (mCallee) {
1.1396 + RefreshDriver(mCallee)->RemoveRefreshObserver(this, Flush_Style);
1.1397 + }
1.1398 + }
1.1399 +};
1.1400 +
1.1401 +nsPoint
1.1402 +ScrollFrameHelper::AsyncScroll::PositionAt(TimeStamp aTime) {
1.1403 + double progressX = mTimingFunctionX.GetSplineValue(ProgressAt(aTime));
1.1404 + double progressY = mTimingFunctionY.GetSplineValue(ProgressAt(aTime));
1.1405 + return nsPoint(NSToCoordRound((1 - progressX) * mStartPos.x + progressX * mDestination.x),
1.1406 + NSToCoordRound((1 - progressY) * mStartPos.y + progressY * mDestination.y));
1.1407 +}
1.1408 +
1.1409 +nsSize
1.1410 +ScrollFrameHelper::AsyncScroll::VelocityAt(TimeStamp aTime) {
1.1411 + double timeProgress = ProgressAt(aTime);
1.1412 + return nsSize(VelocityComponent(timeProgress, mTimingFunctionX,
1.1413 + mStartPos.x, mDestination.x),
1.1414 + VelocityComponent(timeProgress, mTimingFunctionY,
1.1415 + mStartPos.y, mDestination.y));
1.1416 +}
1.1417 +
1.1418 +/*
1.1419 + * Calculate duration, possibly dynamically according to events rate and event origin.
1.1420 + * (also maintain previous timestamps - which are only used here).
1.1421 + */
1.1422 +TimeDuration
1.1423 +ScrollFrameHelper::
1.1424 +AsyncScroll::CalcDurationForEventTime(TimeStamp aTime, nsIAtom *aOrigin) {
1.1425 + if (!aOrigin){
1.1426 + aOrigin = nsGkAtoms::other;
1.1427 + }
1.1428 +
1.1429 + // Read preferences only on first iteration or for a different event origin.
1.1430 + if (mIsFirstIteration || aOrigin != mOrigin) {
1.1431 + mOrigin = aOrigin;
1.1432 + mOriginMinMS = mOriginMaxMS = 0;
1.1433 + bool isOriginSmoothnessEnabled = false;
1.1434 + mIntervalRatio = 1;
1.1435 +
1.1436 + // Default values for all preferences are defined in all.js
1.1437 + static const int32_t kDefaultMinMS = 150, kDefaultMaxMS = 150;
1.1438 + static const bool kDefaultIsSmoothEnabled = true;
1.1439 +
1.1440 + nsAutoCString originName;
1.1441 + aOrigin->ToUTF8String(originName);
1.1442 + nsAutoCString prefBase = NS_LITERAL_CSTRING("general.smoothScroll.") + originName;
1.1443 +
1.1444 + isOriginSmoothnessEnabled = Preferences::GetBool(prefBase.get(), kDefaultIsSmoothEnabled);
1.1445 + if (isOriginSmoothnessEnabled) {
1.1446 + nsAutoCString prefMin = prefBase + NS_LITERAL_CSTRING(".durationMinMS");
1.1447 + nsAutoCString prefMax = prefBase + NS_LITERAL_CSTRING(".durationMaxMS");
1.1448 + mOriginMinMS = Preferences::GetInt(prefMin.get(), kDefaultMinMS);
1.1449 + mOriginMaxMS = Preferences::GetInt(prefMax.get(), kDefaultMaxMS);
1.1450 +
1.1451 + static const int32_t kSmoothScrollMaxAllowedAnimationDurationMS = 10000;
1.1452 + mOriginMaxMS = clamped(mOriginMaxMS, 0, kSmoothScrollMaxAllowedAnimationDurationMS);
1.1453 + mOriginMinMS = clamped(mOriginMinMS, 0, mOriginMaxMS);
1.1454 + }
1.1455 +
1.1456 + // Keep the animation duration longer than the average event intervals
1.1457 + // (to "connect" consecutive scroll animations before the scroll comes to a stop).
1.1458 + static const double kDefaultDurationToIntervalRatio = 2; // Duplicated at all.js
1.1459 + mIntervalRatio = Preferences::GetInt("general.smoothScroll.durationToIntervalRatio",
1.1460 + kDefaultDurationToIntervalRatio * 100) / 100.0;
1.1461 +
1.1462 + // Duration should be at least as long as the intervals -> ratio is at least 1
1.1463 + mIntervalRatio = std::max(1.0, mIntervalRatio);
1.1464 +
1.1465 + if (mIsFirstIteration) {
1.1466 + // Starting a new scroll (i.e. not when extending an existing scroll animation),
1.1467 + // create imaginary prev timestamps with maximum relevant intervals between them.
1.1468 +
1.1469 + // Longest relevant interval (which results in maximum duration)
1.1470 + TimeDuration maxDelta = TimeDuration::FromMilliseconds(mOriginMaxMS / mIntervalRatio);
1.1471 + mPrevEventTime[0] = aTime - maxDelta;
1.1472 + mPrevEventTime[1] = mPrevEventTime[0] - maxDelta;
1.1473 + mPrevEventTime[2] = mPrevEventTime[1] - maxDelta;
1.1474 + }
1.1475 + }
1.1476 +
1.1477 + // Average last 3 delta durations (rounding errors up to 2ms are negligible for us)
1.1478 + int32_t eventsDeltaMs = (aTime - mPrevEventTime[2]).ToMilliseconds() / 3;
1.1479 + mPrevEventTime[2] = mPrevEventTime[1];
1.1480 + mPrevEventTime[1] = mPrevEventTime[0];
1.1481 + mPrevEventTime[0] = aTime;
1.1482 +
1.1483 + // Modulate duration according to events rate (quicker events -> shorter durations).
1.1484 + // The desired effect is to use longer duration when scrolling slowly, such that
1.1485 + // it's easier to follow, but reduce the duration to make it feel more snappy when
1.1486 + // scrolling quickly. To reduce fluctuations of the duration, we average event
1.1487 + // intervals using the recent 4 timestamps (now + three prev -> 3 intervals).
1.1488 + int32_t durationMS = clamped<int32_t>(eventsDeltaMs * mIntervalRatio, mOriginMinMS, mOriginMaxMS);
1.1489 +
1.1490 + return TimeDuration::FromMilliseconds(durationMS);
1.1491 +}
1.1492 +
1.1493 +void
1.1494 +ScrollFrameHelper::AsyncScroll::InitSmoothScroll(TimeStamp aTime,
1.1495 + nsPoint aDestination,
1.1496 + nsIAtom *aOrigin,
1.1497 + const nsRect& aRange) {
1.1498 + mRange = aRange;
1.1499 + TimeDuration duration = CalcDurationForEventTime(aTime, aOrigin);
1.1500 + nsSize currentVelocity(0, 0);
1.1501 + if (!mIsFirstIteration) {
1.1502 + // If an additional event has not changed the destination, then do not let
1.1503 + // another minimum duration reset slow things down. If it would then
1.1504 + // instead continue with the existing timing function.
1.1505 + if (aDestination == mDestination &&
1.1506 + aTime + duration > mStartTime + mDuration)
1.1507 + return;
1.1508 +
1.1509 + currentVelocity = VelocityAt(aTime);
1.1510 + mStartPos = PositionAt(aTime);
1.1511 + }
1.1512 + mStartTime = aTime;
1.1513 + mDuration = duration;
1.1514 + mDestination = aDestination;
1.1515 + InitTimingFunction(mTimingFunctionX, mStartPos.x, currentVelocity.width,
1.1516 + aDestination.x);
1.1517 + InitTimingFunction(mTimingFunctionY, mStartPos.y, currentVelocity.height,
1.1518 + aDestination.y);
1.1519 + mIsFirstIteration = false;
1.1520 +}
1.1521 +
1.1522 +
1.1523 +nscoord
1.1524 +ScrollFrameHelper::AsyncScroll::VelocityComponent(double aTimeProgress,
1.1525 + nsSMILKeySpline& aTimingFunction,
1.1526 + nscoord aStart,
1.1527 + nscoord aDestination)
1.1528 +{
1.1529 + double dt, dxy;
1.1530 + aTimingFunction.GetSplineDerivativeValues(aTimeProgress, dt, dxy);
1.1531 + if (dt == 0)
1.1532 + return dxy >= 0 ? nscoord_MAX : nscoord_MIN;
1.1533 +
1.1534 + const TimeDuration oneSecond = TimeDuration::FromSeconds(1);
1.1535 + double slope = dxy / dt;
1.1536 + return NSToCoordRound(slope * (aDestination - aStart) / (mDuration / oneSecond));
1.1537 +}
1.1538 +
1.1539 +void
1.1540 +ScrollFrameHelper::AsyncScroll::InitTimingFunction(nsSMILKeySpline& aTimingFunction,
1.1541 + nscoord aCurrentPos,
1.1542 + nscoord aCurrentVelocity,
1.1543 + nscoord aDestination)
1.1544 +{
1.1545 + if (aDestination == aCurrentPos || kCurrentVelocityWeighting == 0) {
1.1546 + aTimingFunction.Init(0, 0, 1 - kStopDecelerationWeighting, 1);
1.1547 + return;
1.1548 + }
1.1549 +
1.1550 + const TimeDuration oneSecond = TimeDuration::FromSeconds(1);
1.1551 + double slope = aCurrentVelocity * (mDuration / oneSecond) / (aDestination - aCurrentPos);
1.1552 + double normalization = sqrt(1.0 + slope * slope);
1.1553 + double dt = 1.0 / normalization * kCurrentVelocityWeighting;
1.1554 + double dxy = slope / normalization * kCurrentVelocityWeighting;
1.1555 + aTimingFunction.Init(dt, dxy, 1 - kStopDecelerationWeighting, 1);
1.1556 +}
1.1557 +
1.1558 +static bool
1.1559 +IsSmoothScrollingEnabled()
1.1560 +{
1.1561 + return Preferences::GetBool(SMOOTH_SCROLL_PREF_NAME, false);
1.1562 +}
1.1563 +
1.1564 +class ScrollFrameActivityTracker MOZ_FINAL : public nsExpirationTracker<ScrollFrameHelper,4> {
1.1565 +public:
1.1566 + // Wait for 3-4s between scrolls before we remove our layers.
1.1567 + // That's 4 generations of 1s each.
1.1568 + enum { TIMEOUT_MS = 1000 };
1.1569 + ScrollFrameActivityTracker()
1.1570 + : nsExpirationTracker<ScrollFrameHelper,4>(TIMEOUT_MS) {}
1.1571 + ~ScrollFrameActivityTracker() {
1.1572 + AgeAllGenerations();
1.1573 + }
1.1574 +
1.1575 + virtual void NotifyExpired(ScrollFrameHelper *aObject) {
1.1576 + RemoveObject(aObject);
1.1577 + aObject->MarkInactive();
1.1578 + }
1.1579 +};
1.1580 +
1.1581 +static ScrollFrameActivityTracker *gScrollFrameActivityTracker = nullptr;
1.1582 +
1.1583 +// There are situations when a scroll frame is destroyed and then re-created
1.1584 +// for the same content element. In this case we want to increment the scroll
1.1585 +// generation between the old and new scrollframes. If the new one knew about
1.1586 +// the old one then it could steal the old generation counter and increment it
1.1587 +// but it doesn't have that reference so instead we use a static global to
1.1588 +// ensure the new one gets a fresh value.
1.1589 +static uint32_t sScrollGenerationCounter = 0;
1.1590 +
1.1591 +ScrollFrameHelper::ScrollFrameHelper(nsContainerFrame* aOuter,
1.1592 + bool aIsRoot)
1.1593 + : mHScrollbarBox(nullptr)
1.1594 + , mVScrollbarBox(nullptr)
1.1595 + , mScrolledFrame(nullptr)
1.1596 + , mScrollCornerBox(nullptr)
1.1597 + , mResizerBox(nullptr)
1.1598 + , mOuter(aOuter)
1.1599 + , mAsyncScroll(nullptr)
1.1600 + , mOriginOfLastScroll(nsGkAtoms::other)
1.1601 + , mScrollGeneration(++sScrollGenerationCounter)
1.1602 + , mDestination(0, 0)
1.1603 + , mScrollPosAtLastPaint(0, 0)
1.1604 + , mRestorePos(-1, -1)
1.1605 + , mLastPos(-1, -1)
1.1606 + , mResolution(1.0, 1.0)
1.1607 + , mScrollPosForLayerPixelAlignment(-1, -1)
1.1608 + , mLastUpdateImagesPos(-1, -1)
1.1609 + , mNeverHasVerticalScrollbar(false)
1.1610 + , mNeverHasHorizontalScrollbar(false)
1.1611 + , mHasVerticalScrollbar(false)
1.1612 + , mHasHorizontalScrollbar(false)
1.1613 + , mFrameIsUpdatingScrollbar(false)
1.1614 + , mDidHistoryRestore(false)
1.1615 + , mIsRoot(aIsRoot)
1.1616 + , mClipAllDescendants(aIsRoot)
1.1617 + , mSupppressScrollbarUpdate(false)
1.1618 + , mSkippedScrollbarLayout(false)
1.1619 + , mHadNonInitialReflow(false)
1.1620 + , mHorizontalOverflow(false)
1.1621 + , mVerticalOverflow(false)
1.1622 + , mPostedReflowCallback(false)
1.1623 + , mMayHaveDirtyFixedChildren(false)
1.1624 + , mUpdateScrollbarAttributes(false)
1.1625 + , mCollapsedResizer(false)
1.1626 + , mShouldBuildScrollableLayer(false)
1.1627 + , mHasBeenScrolled(false)
1.1628 + , mIsResolutionSet(false)
1.1629 +{
1.1630 + mScrollingActive = IsAlwaysActive();
1.1631 +
1.1632 + if (LookAndFeel::GetInt(LookAndFeel::eIntID_UseOverlayScrollbars) != 0) {
1.1633 + mScrollbarActivity = new ScrollbarActivity(do_QueryFrame(aOuter));
1.1634 + }
1.1635 +
1.1636 + EnsureImageVisPrefsCached();
1.1637 +}
1.1638 +
1.1639 +ScrollFrameHelper::~ScrollFrameHelper()
1.1640 +{
1.1641 + if (mActivityExpirationState.IsTracked()) {
1.1642 + gScrollFrameActivityTracker->RemoveObject(this);
1.1643 + }
1.1644 + if (gScrollFrameActivityTracker &&
1.1645 + gScrollFrameActivityTracker->IsEmpty()) {
1.1646 + delete gScrollFrameActivityTracker;
1.1647 + gScrollFrameActivityTracker = nullptr;
1.1648 + }
1.1649 +
1.1650 + if (mScrollActivityTimer) {
1.1651 + mScrollActivityTimer->Cancel();
1.1652 + mScrollActivityTimer = nullptr;
1.1653 + }
1.1654 +}
1.1655 +
1.1656 +/*
1.1657 + * Callback function from AsyncScroll, used in ScrollFrameHelper::ScrollTo
1.1658 + */
1.1659 +void
1.1660 +ScrollFrameHelper::AsyncScrollCallback(void* anInstance, mozilla::TimeStamp aTime)
1.1661 +{
1.1662 + ScrollFrameHelper* self = static_cast<ScrollFrameHelper*>(anInstance);
1.1663 + if (!self || !self->mAsyncScroll)
1.1664 + return;
1.1665 +
1.1666 + nsRect range = self->mAsyncScroll->mRange;
1.1667 + if (self->mAsyncScroll->mIsSmoothScroll) {
1.1668 + if (!self->mAsyncScroll->IsFinished(aTime)) {
1.1669 + nsPoint destination = self->mAsyncScroll->PositionAt(aTime);
1.1670 + // Allow this scroll operation to land on any pixel boundary between the
1.1671 + // current position and the final allowed range. (We don't want
1.1672 + // intermediate steps to be more constrained than the final step!)
1.1673 + nsRect intermediateRange =
1.1674 + nsRect(self->GetScrollPosition(), nsSize()).UnionEdges(range);
1.1675 + self->ScrollToImpl(destination, intermediateRange);
1.1676 + // 'self' might be destroyed here
1.1677 + return;
1.1678 + }
1.1679 + }
1.1680 +
1.1681 + // Apply desired destination range since this is the last step of scrolling.
1.1682 + self->mAsyncScroll = nullptr;
1.1683 + nsWeakFrame weakFrame(self->mOuter);
1.1684 + self->ScrollToImpl(self->mDestination, range);
1.1685 + if (!weakFrame.IsAlive()) {
1.1686 + return;
1.1687 + }
1.1688 + // We are done scrolling, set our destination to wherever we actually ended
1.1689 + // up scrolling to.
1.1690 + self->mDestination = self->GetScrollPosition();
1.1691 +}
1.1692 +
1.1693 +void
1.1694 +ScrollFrameHelper::ScrollToCSSPixels(const CSSIntPoint& aScrollPosition)
1.1695 +{
1.1696 + nsPoint current = GetScrollPosition();
1.1697 + CSSIntPoint currentCSSPixels = GetScrollPositionCSSPixels();
1.1698 + nsPoint pt = CSSPoint::ToAppUnits(aScrollPosition);
1.1699 + nscoord halfPixel = nsPresContext::CSSPixelsToAppUnits(0.5f);
1.1700 + nsRect range(pt.x - halfPixel, pt.y - halfPixel, 2*halfPixel - 1, 2*halfPixel - 1);
1.1701 + // XXX I don't think the following blocks are needed anymore, now that
1.1702 + // ScrollToImpl simply tries to scroll an integer number of layer
1.1703 + // pixels from the current position
1.1704 + if (currentCSSPixels.x == aScrollPosition.x) {
1.1705 + pt.x = current.x;
1.1706 + range.x = pt.x;
1.1707 + range.width = 0;
1.1708 + }
1.1709 + if (currentCSSPixels.y == aScrollPosition.y) {
1.1710 + pt.y = current.y;
1.1711 + range.y = pt.y;
1.1712 + range.height = 0;
1.1713 + }
1.1714 + ScrollTo(pt, nsIScrollableFrame::INSTANT, &range);
1.1715 + // 'this' might be destroyed here
1.1716 +}
1.1717 +
1.1718 +void
1.1719 +ScrollFrameHelper::ScrollToCSSPixelsApproximate(const CSSPoint& aScrollPosition,
1.1720 + nsIAtom *aOrigin)
1.1721 +{
1.1722 + nsPoint pt = CSSPoint::ToAppUnits(aScrollPosition);
1.1723 + nscoord halfRange = nsPresContext::CSSPixelsToAppUnits(1000);
1.1724 + nsRect range(pt.x - halfRange, pt.y - halfRange, 2*halfRange - 1, 2*halfRange - 1);
1.1725 + ScrollToWithOrigin(pt, nsIScrollableFrame::INSTANT, aOrigin, &range);
1.1726 + // 'this' might be destroyed here
1.1727 +}
1.1728 +
1.1729 +CSSIntPoint
1.1730 +ScrollFrameHelper::GetScrollPositionCSSPixels()
1.1731 +{
1.1732 + return CSSIntPoint::FromAppUnitsRounded(GetScrollPosition());
1.1733 +}
1.1734 +
1.1735 +/*
1.1736 + * this method wraps calls to ScrollToImpl(), either in one shot or incrementally,
1.1737 + * based on the setting of the smoothness scroll pref
1.1738 + */
1.1739 +void
1.1740 +ScrollFrameHelper::ScrollToWithOrigin(nsPoint aScrollPosition,
1.1741 + nsIScrollableFrame::ScrollMode aMode,
1.1742 + nsIAtom *aOrigin,
1.1743 + const nsRect* aRange)
1.1744 +{
1.1745 + nsRect scrollRange = GetScrollRangeForClamping();
1.1746 + mDestination = scrollRange.ClampPoint(aScrollPosition);
1.1747 +
1.1748 + nsRect range = aRange ? *aRange : nsRect(aScrollPosition, nsSize(0, 0));
1.1749 +
1.1750 + if (aMode == nsIScrollableFrame::INSTANT) {
1.1751 + // Asynchronous scrolling is not allowed, so we'll kill any existing
1.1752 + // async-scrolling process and do an instant scroll.
1.1753 + mAsyncScroll = nullptr;
1.1754 + nsWeakFrame weakFrame(mOuter);
1.1755 + ScrollToImpl(mDestination, range, aOrigin);
1.1756 + if (!weakFrame.IsAlive()) {
1.1757 + return;
1.1758 + }
1.1759 + // We are done scrolling, set our destination to wherever we actually ended
1.1760 + // up scrolling to.
1.1761 + mDestination = GetScrollPosition();
1.1762 + return;
1.1763 + }
1.1764 +
1.1765 + TimeStamp now = TimeStamp::Now();
1.1766 + bool isSmoothScroll = (aMode == nsIScrollableFrame::SMOOTH) &&
1.1767 + IsSmoothScrollingEnabled();
1.1768 +
1.1769 + if (!mAsyncScroll) {
1.1770 + mAsyncScroll = new AsyncScroll(GetScrollPosition());
1.1771 + if (!mAsyncScroll->SetRefreshObserver(this)) {
1.1772 + mAsyncScroll = nullptr;
1.1773 + // Observer setup failed. Scroll the normal way.
1.1774 + nsWeakFrame weakFrame(mOuter);
1.1775 + ScrollToImpl(mDestination, range, aOrigin);
1.1776 + if (!weakFrame.IsAlive()) {
1.1777 + return;
1.1778 + }
1.1779 + // We are done scrolling, set our destination to wherever we actually
1.1780 + // ended up scrolling to.
1.1781 + mDestination = GetScrollPosition();
1.1782 + return;
1.1783 + }
1.1784 + }
1.1785 +
1.1786 + mAsyncScroll->mIsSmoothScroll = isSmoothScroll;
1.1787 +
1.1788 + if (isSmoothScroll) {
1.1789 + mAsyncScroll->InitSmoothScroll(now, mDestination, aOrigin, range);
1.1790 + } else {
1.1791 + mAsyncScroll->Init(range);
1.1792 + }
1.1793 +}
1.1794 +
1.1795 +// We can't use nsContainerFrame::PositionChildViews here because
1.1796 +// we don't want to invalidate views that have moved.
1.1797 +static void AdjustViews(nsIFrame* aFrame)
1.1798 +{
1.1799 + nsView* view = aFrame->GetView();
1.1800 + if (view) {
1.1801 + nsPoint pt;
1.1802 + aFrame->GetParent()->GetClosestView(&pt);
1.1803 + pt += aFrame->GetPosition();
1.1804 + view->SetPosition(pt.x, pt.y);
1.1805 +
1.1806 + return;
1.1807 + }
1.1808 +
1.1809 + if (!(aFrame->GetStateBits() & NS_FRAME_HAS_CHILD_WITH_VIEW)) {
1.1810 + return;
1.1811 + }
1.1812 +
1.1813 + // Call AdjustViews recursively for all child frames except the popup list as
1.1814 + // the views for popups are not scrolled.
1.1815 + nsIFrame::ChildListIterator lists(aFrame);
1.1816 + for (; !lists.IsDone(); lists.Next()) {
1.1817 + if (lists.CurrentID() == nsIFrame::kPopupList) {
1.1818 + continue;
1.1819 + }
1.1820 + nsFrameList::Enumerator childFrames(lists.CurrentList());
1.1821 + for (; !childFrames.AtEnd(); childFrames.Next()) {
1.1822 + AdjustViews(childFrames.get());
1.1823 + }
1.1824 + }
1.1825 +}
1.1826 +
1.1827 +static bool
1.1828 +CanScrollWithBlitting(nsIFrame* aFrame)
1.1829 +{
1.1830 + if (aFrame->GetStateBits() & NS_SCROLLFRAME_INVALIDATE_CONTENTS_ON_SCROLL)
1.1831 + return false;
1.1832 +
1.1833 + for (nsIFrame* f = aFrame; f;
1.1834 + f = nsLayoutUtils::GetCrossDocParentFrame(f)) {
1.1835 + if (nsSVGIntegrationUtils::UsingEffectsForFrame(f) ||
1.1836 + f->IsFrameOfType(nsIFrame::eSVG) ||
1.1837 + f->GetStateBits() & NS_FRAME_NO_COMPONENT_ALPHA) {
1.1838 + return false;
1.1839 + }
1.1840 + if (nsLayoutUtils::IsPopup(f))
1.1841 + break;
1.1842 + }
1.1843 + return true;
1.1844 +}
1.1845 +
1.1846 +bool ScrollFrameHelper::IsIgnoringViewportClipping() const
1.1847 +{
1.1848 + if (!mIsRoot)
1.1849 + return false;
1.1850 + nsSubDocumentFrame* subdocFrame = static_cast<nsSubDocumentFrame*>
1.1851 + (nsLayoutUtils::GetCrossDocParentFrame(mOuter->PresContext()->PresShell()->GetRootFrame()));
1.1852 + return subdocFrame && !subdocFrame->ShouldClipSubdocument();
1.1853 +}
1.1854 +
1.1855 +bool ScrollFrameHelper::ShouldClampScrollPosition() const
1.1856 +{
1.1857 + if (!mIsRoot)
1.1858 + return true;
1.1859 + nsSubDocumentFrame* subdocFrame = static_cast<nsSubDocumentFrame*>
1.1860 + (nsLayoutUtils::GetCrossDocParentFrame(mOuter->PresContext()->PresShell()->GetRootFrame()));
1.1861 + return !subdocFrame || subdocFrame->ShouldClampScrollPosition();
1.1862 +}
1.1863 +
1.1864 +bool ScrollFrameHelper::IsAlwaysActive() const
1.1865 +{
1.1866 + if (nsDisplayItem::ForceActiveLayers()) {
1.1867 + return true;
1.1868 + }
1.1869 +
1.1870 + const nsStyleDisplay* disp = mOuter->StyleDisplay();
1.1871 + if (disp && (disp->mWillChangeBitField & NS_STYLE_WILL_CHANGE_SCROLL)) {
1.1872 + return true;
1.1873 + }
1.1874 +
1.1875 + // Unless this is the root scrollframe for a non-chrome document
1.1876 + // which is the direct child of a chrome document, we default to not
1.1877 + // being "active".
1.1878 + if (!(mIsRoot && mOuter->PresContext()->IsRootContentDocument())) {
1.1879 + return false;
1.1880 + }
1.1881 +
1.1882 + // If we have scrolled before, then we should stay active.
1.1883 + if (mHasBeenScrolled) {
1.1884 + return true;
1.1885 + }
1.1886 +
1.1887 + // If we're overflow:hidden, then start as inactive until
1.1888 + // we get scrolled manually.
1.1889 + ScrollbarStyles styles = GetScrollbarStylesFromFrame();
1.1890 + return (styles.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN &&
1.1891 + styles.mVertical != NS_STYLE_OVERFLOW_HIDDEN);
1.1892 +}
1.1893 +
1.1894 +void ScrollFrameHelper::MarkInactive()
1.1895 +{
1.1896 + if (IsAlwaysActive() || !mScrollingActive)
1.1897 + return;
1.1898 +
1.1899 + mScrollingActive = false;
1.1900 + mOuter->InvalidateFrameSubtree();
1.1901 +}
1.1902 +
1.1903 +void ScrollFrameHelper::MarkActive()
1.1904 +{
1.1905 + mScrollingActive = true;
1.1906 + if (IsAlwaysActive())
1.1907 + return;
1.1908 +
1.1909 + if (mActivityExpirationState.IsTracked()) {
1.1910 + gScrollFrameActivityTracker->MarkUsed(this);
1.1911 + } else {
1.1912 + if (!gScrollFrameActivityTracker) {
1.1913 + gScrollFrameActivityTracker = new ScrollFrameActivityTracker();
1.1914 + }
1.1915 + gScrollFrameActivityTracker->AddObject(this);
1.1916 + }
1.1917 +}
1.1918 +
1.1919 +void ScrollFrameHelper::ScrollVisual(nsPoint aOldScrolledFramePos)
1.1920 +{
1.1921 + // Mark this frame as having been scrolled. If this is the root
1.1922 + // scroll frame of a content document, then IsAlwaysActive()
1.1923 + // will return true from now on and MarkInactive() won't
1.1924 + // have any effect.
1.1925 + mHasBeenScrolled = true;
1.1926 +
1.1927 + AdjustViews(mScrolledFrame);
1.1928 + // We need to call this after fixing up the view positions
1.1929 + // to be consistent with the frame hierarchy.
1.1930 + bool canScrollWithBlitting = CanScrollWithBlitting(mOuter);
1.1931 + mOuter->RemoveStateBits(NS_SCROLLFRAME_INVALIDATE_CONTENTS_ON_SCROLL);
1.1932 + if (IsScrollingActive()) {
1.1933 + if (!canScrollWithBlitting) {
1.1934 + MarkInactive();
1.1935 + }
1.1936 + }
1.1937 + if (canScrollWithBlitting) {
1.1938 + MarkActive();
1.1939 + }
1.1940 +
1.1941 + mOuter->SchedulePaint();
1.1942 +}
1.1943 +
1.1944 +/**
1.1945 + * Clamp desired scroll position aDesired and range [aDestLower, aDestUpper]
1.1946 + * to [aBoundLower, aBoundUpper] and then select the appunit value from among
1.1947 + * aBoundLower, aBoundUpper and those such that (aDesired - aCurrent) *
1.1948 + * aRes/aAppUnitsPerPixel is an integer (or as close as we can get
1.1949 + * modulo rounding to appunits) that is in [aDestLower, aDestUpper] and
1.1950 + * closest to aDesired. If no such value exists, return the nearest in
1.1951 + * [aDestLower, aDestUpper].
1.1952 + */
1.1953 +static nscoord
1.1954 +ClampAndAlignWithPixels(nscoord aDesired,
1.1955 + nscoord aBoundLower, nscoord aBoundUpper,
1.1956 + nscoord aDestLower, nscoord aDestUpper,
1.1957 + nscoord aAppUnitsPerPixel, double aRes,
1.1958 + nscoord aCurrent)
1.1959 +{
1.1960 + // Intersect scroll range with allowed range, by clamping the ends
1.1961 + // of aRange to be within bounds
1.1962 + nscoord destLower = clamped(aDestLower, aBoundLower, aBoundUpper);
1.1963 + nscoord destUpper = clamped(aDestUpper, aBoundLower, aBoundUpper);
1.1964 +
1.1965 + nscoord desired = clamped(aDesired, destLower, destUpper);
1.1966 +
1.1967 + double currentLayerVal = (aRes*aCurrent)/aAppUnitsPerPixel;
1.1968 + double desiredLayerVal = (aRes*desired)/aAppUnitsPerPixel;
1.1969 + double delta = desiredLayerVal - currentLayerVal;
1.1970 + double nearestLayerVal = NS_round(delta) + currentLayerVal;
1.1971 +
1.1972 + // Convert back from ThebesLayer space to appunits relative to the top-left
1.1973 + // of the scrolled frame.
1.1974 + nscoord aligned =
1.1975 + NSToCoordRoundWithClamp(nearestLayerVal*aAppUnitsPerPixel/aRes);
1.1976 +
1.1977 + // Use a bound if it is within the allowed range and closer to desired than
1.1978 + // the nearest pixel-aligned value.
1.1979 + if (aBoundUpper == destUpper &&
1.1980 + static_cast<decltype(Abs(desired))>(aBoundUpper - desired) <
1.1981 + Abs(desired - aligned))
1.1982 + return aBoundUpper;
1.1983 +
1.1984 + if (aBoundLower == destLower &&
1.1985 + static_cast<decltype(Abs(desired))>(desired - aBoundLower) <
1.1986 + Abs(aligned - desired))
1.1987 + return aBoundLower;
1.1988 +
1.1989 + // Accept the nearest pixel-aligned value if it is within the allowed range.
1.1990 + if (aligned >= destLower && aligned <= destUpper)
1.1991 + return aligned;
1.1992 +
1.1993 + // Check if opposite pixel boundary fits into allowed range.
1.1994 + double oppositeLayerVal =
1.1995 + nearestLayerVal + ((nearestLayerVal < desiredLayerVal) ? 1.0 : -1.0);
1.1996 + nscoord opposite =
1.1997 + NSToCoordRoundWithClamp(oppositeLayerVal*aAppUnitsPerPixel/aRes);
1.1998 + if (opposite >= destLower && opposite <= destUpper) {
1.1999 + return opposite;
1.2000 + }
1.2001 +
1.2002 + // No alignment available.
1.2003 + return desired;
1.2004 +}
1.2005 +
1.2006 +/**
1.2007 + * Clamp desired scroll position aPt to aBounds and then snap
1.2008 + * it to the same layer pixel edges as aCurrent, keeping it within aRange
1.2009 + * during snapping. aCurrent is the current scroll position.
1.2010 + */
1.2011 +static nsPoint
1.2012 +ClampAndAlignWithLayerPixels(const nsPoint& aPt,
1.2013 + const nsRect& aBounds,
1.2014 + const nsRect& aRange,
1.2015 + const nsPoint& aCurrent,
1.2016 + nscoord aAppUnitsPerPixel,
1.2017 + const gfxSize& aScale)
1.2018 +{
1.2019 + return nsPoint(ClampAndAlignWithPixels(aPt.x, aBounds.x, aBounds.XMost(),
1.2020 + aRange.x, aRange.XMost(),
1.2021 + aAppUnitsPerPixel, aScale.width,
1.2022 + aCurrent.x),
1.2023 + ClampAndAlignWithPixels(aPt.y, aBounds.y, aBounds.YMost(),
1.2024 + aRange.y, aRange.YMost(),
1.2025 + aAppUnitsPerPixel, aScale.height,
1.2026 + aCurrent.y));
1.2027 +}
1.2028 +
1.2029 +/* static */ void
1.2030 +ScrollFrameHelper::ScrollActivityCallback(nsITimer *aTimer, void* anInstance)
1.2031 +{
1.2032 + ScrollFrameHelper* self = static_cast<ScrollFrameHelper*>(anInstance);
1.2033 +
1.2034 + // Fire the synth mouse move.
1.2035 + self->mScrollActivityTimer->Cancel();
1.2036 + self->mScrollActivityTimer = nullptr;
1.2037 + self->mOuter->PresContext()->PresShell()->SynthesizeMouseMove(true);
1.2038 +}
1.2039 +
1.2040 +
1.2041 +void
1.2042 +ScrollFrameHelper::ScheduleSyntheticMouseMove()
1.2043 +{
1.2044 + if (!mScrollActivityTimer) {
1.2045 + mScrollActivityTimer = do_CreateInstance("@mozilla.org/timer;1");
1.2046 + if (!mScrollActivityTimer)
1.2047 + return;
1.2048 + }
1.2049 +
1.2050 + mScrollActivityTimer->InitWithFuncCallback(
1.2051 + ScrollActivityCallback, this, 100, nsITimer::TYPE_ONE_SHOT);
1.2052 +}
1.2053 +
1.2054 +void
1.2055 +ScrollFrameHelper::ScrollToImpl(nsPoint aPt, const nsRect& aRange, nsIAtom* aOrigin)
1.2056 +{
1.2057 + if (aOrigin == nullptr) {
1.2058 + // If no origin was specified, we still want to set it to something that's
1.2059 + // non-null, so that we can use nullness to distinguish if the frame was scrolled
1.2060 + // at all. Default it to some generic placeholder.
1.2061 + aOrigin = nsGkAtoms::other;
1.2062 + }
1.2063 +
1.2064 + nsPresContext* presContext = mOuter->PresContext();
1.2065 + nscoord appUnitsPerDevPixel = presContext->AppUnitsPerDevPixel();
1.2066 + // 'scale' is our estimate of the scale factor that will be applied
1.2067 + // when rendering the scrolled content to its own ThebesLayer.
1.2068 + gfxSize scale = FrameLayerBuilder::GetThebesLayerScaleForFrame(mScrolledFrame);
1.2069 + nsPoint curPos = GetScrollPosition();
1.2070 + nsPoint alignWithPos = mScrollPosForLayerPixelAlignment == nsPoint(-1,-1)
1.2071 + ? curPos : mScrollPosForLayerPixelAlignment;
1.2072 + // Try to align aPt with curPos so they have an integer number of layer
1.2073 + // pixels between them. This gives us the best chance of scrolling without
1.2074 + // having to invalidate due to changes in subpixel rendering.
1.2075 + // Note that when we actually draw into a ThebesLayer, the coordinates
1.2076 + // that get mapped onto the layer buffer pixels are from the display list,
1.2077 + // which are relative to the display root frame's top-left increasing down,
1.2078 + // whereas here our coordinates are scroll positions which increase upward
1.2079 + // and are relative to the scrollport top-left. This difference doesn't actually
1.2080 + // matter since all we are about is that there be an integer number of
1.2081 + // layer pixels between pt and curPos.
1.2082 + nsPoint pt =
1.2083 + ClampAndAlignWithLayerPixels(aPt,
1.2084 + GetScrollRangeForClamping(),
1.2085 + aRange,
1.2086 + alignWithPos,
1.2087 + appUnitsPerDevPixel,
1.2088 + scale);
1.2089 + if (pt == curPos) {
1.2090 + return;
1.2091 + }
1.2092 +
1.2093 + bool needImageVisibilityUpdate = (mLastUpdateImagesPos == nsPoint(-1,-1));
1.2094 +
1.2095 + nsPoint dist(std::abs(pt.x - mLastUpdateImagesPos.x),
1.2096 + std::abs(pt.y - mLastUpdateImagesPos.y));
1.2097 + nsSize scrollPortSize = GetScrollPositionClampingScrollPortSize();
1.2098 + nscoord horzAllowance = std::max(scrollPortSize.width / std::max(sHorzScrollFraction, 1),
1.2099 + nsPresContext::AppUnitsPerCSSPixel());
1.2100 + nscoord vertAllowance = std::max(scrollPortSize.height / std::max(sVertScrollFraction, 1),
1.2101 + nsPresContext::AppUnitsPerCSSPixel());
1.2102 + if (dist.x >= horzAllowance || dist.y >= vertAllowance) {
1.2103 + needImageVisibilityUpdate = true;
1.2104 + }
1.2105 +
1.2106 + if (needImageVisibilityUpdate) {
1.2107 + presContext->PresShell()->ScheduleImageVisibilityUpdate();
1.2108 + }
1.2109 +
1.2110 + // notify the listeners.
1.2111 + for (uint32_t i = 0; i < mListeners.Length(); i++) {
1.2112 + mListeners[i]->ScrollPositionWillChange(pt.x, pt.y);
1.2113 + }
1.2114 +
1.2115 + nsPoint oldScrollFramePos = mScrolledFrame->GetPosition();
1.2116 + // Update frame position for scrolling
1.2117 + mScrolledFrame->SetPosition(mScrollPort.TopLeft() - pt);
1.2118 + mOriginOfLastScroll = aOrigin;
1.2119 + mScrollGeneration = ++sScrollGenerationCounter;
1.2120 +
1.2121 + // We pass in the amount to move visually
1.2122 + ScrollVisual(oldScrollFramePos);
1.2123 +
1.2124 + ScheduleSyntheticMouseMove();
1.2125 + nsWeakFrame weakFrame(mOuter);
1.2126 + UpdateScrollbarPosition();
1.2127 + if (!weakFrame.IsAlive()) {
1.2128 + return;
1.2129 + }
1.2130 + PostScrollEvent();
1.2131 +
1.2132 + // notify the listeners.
1.2133 + for (uint32_t i = 0; i < mListeners.Length(); i++) {
1.2134 + mListeners[i]->ScrollPositionDidChange(pt.x, pt.y);
1.2135 + }
1.2136 +
1.2137 + nsCOMPtr<nsIDocShell> docShell = presContext->GetDocShell();
1.2138 + if (docShell) {
1.2139 + docShell->NotifyScrollObservers();
1.2140 + }
1.2141 +}
1.2142 +
1.2143 +static int32_t
1.2144 +MaxZIndexInList(nsDisplayList* aList, nsDisplayListBuilder* aBuilder)
1.2145 +{
1.2146 + int32_t maxZIndex = 0;
1.2147 + for (nsDisplayItem* item = aList->GetBottom(); item; item = item->GetAbove()) {
1.2148 + maxZIndex = std::max(maxZIndex, item->ZIndex());
1.2149 + }
1.2150 + return maxZIndex;
1.2151 +}
1.2152 +
1.2153 +static void
1.2154 +AppendToTop(nsDisplayListBuilder* aBuilder, const nsDisplayListSet& aLists,
1.2155 + nsDisplayList* aSource, nsIFrame* aSourceFrame, bool aOwnLayer,
1.2156 + uint32_t aFlags, mozilla::layers::FrameMetrics::ViewID aScrollTargetId,
1.2157 + bool aPositioned)
1.2158 +{
1.2159 + if (aSource->IsEmpty())
1.2160 + return;
1.2161 +
1.2162 + nsDisplayWrapList* newItem = aOwnLayer?
1.2163 + new (aBuilder) nsDisplayOwnLayer(aBuilder, aSourceFrame, aSource,
1.2164 + aFlags, aScrollTargetId) :
1.2165 + new (aBuilder) nsDisplayWrapList(aBuilder, aSourceFrame, aSource);
1.2166 +
1.2167 + if (aPositioned) {
1.2168 + // We want overlay scrollbars to always be on top of the scrolled content,
1.2169 + // but we don't want them to unnecessarily cover overlapping elements from
1.2170 + // outside our scroll frame.
1.2171 + nsDisplayList* positionedDescendants = aLists.PositionedDescendants();
1.2172 + if (!positionedDescendants->IsEmpty()) {
1.2173 + newItem->SetOverrideZIndex(MaxZIndexInList(positionedDescendants, aBuilder));
1.2174 + positionedDescendants->AppendNewToTop(newItem);
1.2175 + } else {
1.2176 + aLists.Outlines()->AppendNewToTop(newItem);
1.2177 + }
1.2178 + } else {
1.2179 + aLists.BorderBackground()->AppendNewToTop(newItem);
1.2180 + }
1.2181 +}
1.2182 +
1.2183 +struct HoveredStateComparator
1.2184 +{
1.2185 + bool Equals(nsIFrame* A, nsIFrame* B) const {
1.2186 + bool aHovered = A->GetContent()->HasAttr(kNameSpaceID_None,
1.2187 + nsGkAtoms::hover);
1.2188 + bool bHovered = B->GetContent()->HasAttr(kNameSpaceID_None,
1.2189 + nsGkAtoms::hover);
1.2190 + return aHovered == bHovered;
1.2191 + }
1.2192 + bool LessThan(nsIFrame* A, nsIFrame* B) const {
1.2193 + bool aHovered = A->GetContent()->HasAttr(kNameSpaceID_None,
1.2194 + nsGkAtoms::hover);
1.2195 + bool bHovered = B->GetContent()->HasAttr(kNameSpaceID_None,
1.2196 + nsGkAtoms::hover);
1.2197 + return !aHovered && bHovered;
1.2198 + }
1.2199 +};
1.2200 +
1.2201 +void
1.2202 +ScrollFrameHelper::AppendScrollPartsTo(nsDisplayListBuilder* aBuilder,
1.2203 + const nsRect& aDirtyRect,
1.2204 + const nsDisplayListSet& aLists,
1.2205 + bool& aCreateLayer,
1.2206 + bool aPositioned)
1.2207 +{
1.2208 + nsITheme* theme = mOuter->PresContext()->GetTheme();
1.2209 + if (theme &&
1.2210 + theme->ShouldHideScrollbars()) {
1.2211 + return;
1.2212 + }
1.2213 +
1.2214 + bool overlayScrollbars =
1.2215 + LookAndFeel::GetInt(LookAndFeel::eIntID_UseOverlayScrollbars) != 0;
1.2216 +
1.2217 + nsAutoTArray<nsIFrame*, 3> scrollParts;
1.2218 + for (nsIFrame* kid = mOuter->GetFirstPrincipalChild(); kid; kid = kid->GetNextSibling()) {
1.2219 + if (kid == mScrolledFrame ||
1.2220 + (kid->IsPositioned() || overlayScrollbars) != aPositioned)
1.2221 + continue;
1.2222 +
1.2223 + scrollParts.AppendElement(kid);
1.2224 + }
1.2225 +
1.2226 + mozilla::layers::FrameMetrics::ViewID scrollTargetId = aCreateLayer
1.2227 + ? nsLayoutUtils::FindOrCreateIDFor(mScrolledFrame->GetContent())
1.2228 + : mozilla::layers::FrameMetrics::NULL_SCROLL_ID;
1.2229 +
1.2230 + scrollParts.Sort(HoveredStateComparator());
1.2231 +
1.2232 + for (uint32_t i = 0; i < scrollParts.Length(); ++i) {
1.2233 + nsDisplayListCollection partList;
1.2234 + mOuter->BuildDisplayListForChild(
1.2235 + aBuilder, scrollParts[i], aDirtyRect, partList,
1.2236 + nsIFrame::DISPLAY_CHILD_FORCE_STACKING_CONTEXT);
1.2237 +
1.2238 + uint32_t flags = 0;
1.2239 + if (scrollParts[i] == mVScrollbarBox) {
1.2240 + flags |= nsDisplayOwnLayer::VERTICAL_SCROLLBAR;
1.2241 + }
1.2242 + if (scrollParts[i] == mHScrollbarBox) {
1.2243 + flags |= nsDisplayOwnLayer::HORIZONTAL_SCROLLBAR;
1.2244 + }
1.2245 +
1.2246 + // DISPLAY_CHILD_FORCE_STACKING_CONTEXT put everything into
1.2247 + // partList.PositionedDescendants().
1.2248 + ::AppendToTop(aBuilder, aLists,
1.2249 + partList.PositionedDescendants(), scrollParts[i],
1.2250 + aCreateLayer, flags, scrollTargetId, aPositioned);
1.2251 + }
1.2252 +}
1.2253 +
1.2254 +class ScrollLayerWrapper : public nsDisplayWrapper
1.2255 +{
1.2256 +public:
1.2257 + ScrollLayerWrapper(nsIFrame* aScrollFrame, nsIFrame* aScrolledFrame)
1.2258 + : mCount(0)
1.2259 + , mProps(aScrolledFrame->Properties())
1.2260 + , mScrollFrame(aScrollFrame)
1.2261 + , mScrolledFrame(aScrolledFrame)
1.2262 + {
1.2263 + SetCount(0);
1.2264 + }
1.2265 +
1.2266 + virtual nsDisplayItem* WrapList(nsDisplayListBuilder* aBuilder,
1.2267 + nsIFrame* aFrame,
1.2268 + nsDisplayList* aList) MOZ_OVERRIDE {
1.2269 + SetCount(++mCount);
1.2270 + return new (aBuilder) nsDisplayScrollLayer(aBuilder, aList, mScrolledFrame, mScrolledFrame, mScrollFrame);
1.2271 + }
1.2272 +
1.2273 + virtual nsDisplayItem* WrapItem(nsDisplayListBuilder* aBuilder,
1.2274 + nsDisplayItem* aItem) MOZ_OVERRIDE {
1.2275 +
1.2276 + SetCount(++mCount);
1.2277 + return new (aBuilder) nsDisplayScrollLayer(aBuilder, aItem, aItem->Frame(), mScrolledFrame, mScrollFrame);
1.2278 + }
1.2279 +
1.2280 +protected:
1.2281 + void SetCount(intptr_t aCount) {
1.2282 + mProps.Set(nsIFrame::ScrollLayerCount(), reinterpret_cast<void*>(aCount));
1.2283 + }
1.2284 +
1.2285 + intptr_t mCount;
1.2286 + FrameProperties mProps;
1.2287 + nsIFrame* mScrollFrame;
1.2288 + nsIFrame* mScrolledFrame;
1.2289 +};
1.2290 +
1.2291 +/* static */ bool ScrollFrameHelper::sImageVisPrefsCached = false;
1.2292 +/* static */ uint32_t ScrollFrameHelper::sHorzExpandScrollPort = 0;
1.2293 +/* static */ uint32_t ScrollFrameHelper::sVertExpandScrollPort = 1;
1.2294 +/* static */ int32_t ScrollFrameHelper::sHorzScrollFraction = 2;
1.2295 +/* static */ int32_t ScrollFrameHelper::sVertScrollFraction = 2;
1.2296 +
1.2297 +/* static */ void
1.2298 +ScrollFrameHelper::EnsureImageVisPrefsCached()
1.2299 +{
1.2300 + if (!sImageVisPrefsCached) {
1.2301 + Preferences::AddUintVarCache(&sHorzExpandScrollPort,
1.2302 + "layout.imagevisibility.numscrollportwidths", (uint32_t)0);
1.2303 + Preferences::AddUintVarCache(&sVertExpandScrollPort,
1.2304 + "layout.imagevisibility.numscrollportheights", 1);
1.2305 +
1.2306 + Preferences::AddIntVarCache(&sHorzScrollFraction,
1.2307 + "layout.imagevisibility.amountscrollbeforeupdatehorizontal", 2);
1.2308 + Preferences::AddIntVarCache(&sVertScrollFraction,
1.2309 + "layout.imagevisibility.amountscrollbeforeupdatevertical", 2);
1.2310 +
1.2311 + sImageVisPrefsCached = true;
1.2312 + }
1.2313 +}
1.2314 +
1.2315 +nsRect
1.2316 +ScrollFrameHelper::ExpandRect(const nsRect& aRect) const
1.2317 +{
1.2318 + // We don't want to expand a rect in a direction that we can't scroll, so we
1.2319 + // check the scroll range.
1.2320 + nsRect scrollRange = GetScrollRangeForClamping();
1.2321 + nsPoint scrollPos = GetScrollPosition();
1.2322 + nsMargin expand(0, 0, 0, 0);
1.2323 +
1.2324 + nscoord vertShift = sVertExpandScrollPort * aRect.height;
1.2325 + if (scrollRange.y < scrollPos.y) {
1.2326 + expand.top = vertShift;
1.2327 + }
1.2328 + if (scrollPos.y < scrollRange.YMost()) {
1.2329 + expand.bottom = vertShift;
1.2330 + }
1.2331 +
1.2332 + nscoord horzShift = sHorzExpandScrollPort * aRect.width;
1.2333 + if (scrollRange.x < scrollPos.x) {
1.2334 + expand.left = horzShift;
1.2335 + }
1.2336 + if (scrollPos.x < scrollRange.XMost()) {
1.2337 + expand.right = horzShift;
1.2338 + }
1.2339 +
1.2340 + nsRect rect = aRect;
1.2341 + rect.Inflate(expand);
1.2342 + return rect;
1.2343 +}
1.2344 +
1.2345 +static bool
1.2346 +ShouldBeClippedByFrame(nsIFrame* aClipFrame, nsIFrame* aClippedFrame)
1.2347 +{
1.2348 + return nsLayoutUtils::IsProperAncestorFrame(aClipFrame, aClippedFrame);
1.2349 +}
1.2350 +
1.2351 +static void
1.2352 +ClipItemsExceptCaret(nsDisplayList* aList, nsDisplayListBuilder* aBuilder,
1.2353 + nsIFrame* aClipFrame, const DisplayItemClip& aClip)
1.2354 +{
1.2355 + nsDisplayItem* i = aList->GetBottom();
1.2356 + for (; i; i = i->GetAbove()) {
1.2357 + if (!::ShouldBeClippedByFrame(aClipFrame, i->Frame())) {
1.2358 + continue;
1.2359 + }
1.2360 +
1.2361 + bool unused;
1.2362 + nsRect bounds = i->GetBounds(aBuilder, &unused);
1.2363 + bool isAffectedByClip = aClip.IsRectAffectedByClip(bounds);
1.2364 + if (isAffectedByClip && nsDisplayItem::TYPE_CARET == i->GetType()) {
1.2365 + // Don't clip the caret if it overflows vertically only, and by half
1.2366 + // its height at most. This is to avoid clipping it when the line-height
1.2367 + // is small.
1.2368 + auto half = bounds.height / 2;
1.2369 + bounds.y += half;
1.2370 + bounds.height -= half;
1.2371 + isAffectedByClip = aClip.IsRectAffectedByClip(bounds);
1.2372 + if (isAffectedByClip) {
1.2373 + // Don't clip the caret if it's just outside on the right side.
1.2374 + nsRect rightSide(bounds.x - 1, bounds.y, 1, bounds.height);
1.2375 + isAffectedByClip = aClip.IsRectAffectedByClip(rightSide);
1.2376 + // Also, avoid clipping it in a zero-height line box (heuristic only).
1.2377 + if (isAffectedByClip) {
1.2378 + isAffectedByClip = i->Frame()->GetRect().height != 0;
1.2379 + }
1.2380 + }
1.2381 + }
1.2382 + if (isAffectedByClip) {
1.2383 + DisplayItemClip newClip;
1.2384 + newClip.IntersectWith(i->GetClip());
1.2385 + newClip.IntersectWith(aClip);
1.2386 + i->SetClip(aBuilder, newClip);
1.2387 + }
1.2388 + nsDisplayList* children = i->GetSameCoordinateSystemChildren();
1.2389 + if (children) {
1.2390 + ClipItemsExceptCaret(children, aBuilder, aClipFrame, aClip);
1.2391 + }
1.2392 + }
1.2393 +}
1.2394 +
1.2395 +static void
1.2396 +ClipListsExceptCaret(nsDisplayListCollection* aLists,
1.2397 + nsDisplayListBuilder* aBuilder,
1.2398 + nsIFrame* aClipFrame,
1.2399 + const DisplayItemClip& aClip)
1.2400 +{
1.2401 + ::ClipItemsExceptCaret(aLists->BorderBackground(), aBuilder, aClipFrame, aClip);
1.2402 + ::ClipItemsExceptCaret(aLists->BlockBorderBackgrounds(), aBuilder, aClipFrame, aClip);
1.2403 + ::ClipItemsExceptCaret(aLists->Floats(), aBuilder, aClipFrame, aClip);
1.2404 + ::ClipItemsExceptCaret(aLists->PositionedDescendants(), aBuilder, aClipFrame, aClip);
1.2405 + ::ClipItemsExceptCaret(aLists->Outlines(), aBuilder, aClipFrame, aClip);
1.2406 + ::ClipItemsExceptCaret(aLists->Content(), aBuilder, aClipFrame, aClip);
1.2407 +}
1.2408 +
1.2409 +static bool
1.2410 +DisplayportExceedsMaxTextureSize(nsPresContext* aPresContext, const nsRect& aDisplayPort)
1.2411 +{
1.2412 +#ifdef MOZ_WIDGET_GONK
1.2413 + // On B2G we actively run into max texture size limits because the displayport-sizing code
1.2414 + // in the AsyncPanZoomController code is slightly busted (bug 957668 will fix it properly).
1.2415 + // We sometimes end up requesting displayports for which the corresponding layer will be
1.2416 + // larger than the max GL texture size (which we assume to be 4096 here).
1.2417 + // If we run into this case, we should just not use the displayport at all and fall back to
1.2418 + // just making a ScrollInfoLayer so that we use the APZC's synchronous scrolling fallback
1.2419 + // mechanism.
1.2420 + // Note also that if we don't do this here, it is quite likely that the parent B2G process
1.2421 + // will kill this child process to prevent OOMs (see the patch that landed as part of bug
1.2422 + // 965945 for details).
1.2423 + gfxSize resolution = aPresContext->PresShell()->GetCumulativeResolution();
1.2424 + return (aPresContext->AppUnitsToDevPixels(aDisplayPort.width) * resolution.width > 4096) ||
1.2425 + (aPresContext->AppUnitsToDevPixels(aDisplayPort.height) * resolution.height > 4096);
1.2426 +#else
1.2427 + return false;
1.2428 +#endif
1.2429 +}
1.2430 +
1.2431 +void
1.2432 +ScrollFrameHelper::BuildDisplayList(nsDisplayListBuilder* aBuilder,
1.2433 + const nsRect& aDirtyRect,
1.2434 + const nsDisplayListSet& aLists)
1.2435 +{
1.2436 + if (aBuilder->IsForImageVisibility()) {
1.2437 + mLastUpdateImagesPos = GetScrollPosition();
1.2438 + }
1.2439 +
1.2440 + mOuter->DisplayBorderBackgroundOutline(aBuilder, aLists);
1.2441 +
1.2442 + if (aBuilder->IsPaintingToWindow()) {
1.2443 + mScrollPosAtLastPaint = GetScrollPosition();
1.2444 + if (IsScrollingActive() && !CanScrollWithBlitting(mOuter)) {
1.2445 + MarkInactive();
1.2446 + }
1.2447 + if (IsScrollingActive()) {
1.2448 + if (mScrollPosForLayerPixelAlignment == nsPoint(-1,-1)) {
1.2449 + mScrollPosForLayerPixelAlignment = mScrollPosAtLastPaint;
1.2450 + }
1.2451 + } else {
1.2452 + mScrollPosForLayerPixelAlignment = nsPoint(-1,-1);
1.2453 + }
1.2454 + }
1.2455 +
1.2456 + // We put scrollbars in their own layers when this is the root scroll
1.2457 + // frame and we are a toplevel content document. In this situation, the
1.2458 + // scrollbar(s) would normally be assigned their own layer anyway, since
1.2459 + // they're not scrolled with the rest of the document. But when both
1.2460 + // scrollbars are visible, the layer's visible rectangle would be the size
1.2461 + // of the viewport, so most layer implementations would create a layer buffer
1.2462 + // that's much larger than necessary. Creating independent layers for each
1.2463 + // scrollbar works around the problem.
1.2464 + bool createLayersForScrollbars = mIsRoot &&
1.2465 + mOuter->PresContext()->IsRootContentDocument();
1.2466 +
1.2467 + if (aBuilder->GetIgnoreScrollFrame() == mOuter || IsIgnoringViewportClipping()) {
1.2468 +
1.2469 + // If we are a root scroll frame that has a display port we want to add
1.2470 + // scrollbars, they will be children of the scrollable layer, but they get
1.2471 + // adjusted by the APZC automatically.
1.2472 + bool addScrollBars = mIsRoot &&
1.2473 + nsLayoutUtils::GetDisplayPort(mOuter->GetContent()) &&
1.2474 + !aBuilder->IsForEventDelivery();
1.2475 + // For now, don't add them for display root documents, cause we've never
1.2476 + // had them there.
1.2477 + if (aBuilder->RootReferenceFrame()->PresContext() == mOuter->PresContext()) {
1.2478 + addScrollBars = false;
1.2479 + }
1.2480 +
1.2481 + if (addScrollBars) {
1.2482 + // Add classic scrollbars.
1.2483 + AppendScrollPartsTo(aBuilder, aDirtyRect, aLists, createLayersForScrollbars,
1.2484 + false);
1.2485 + }
1.2486 +
1.2487 + // Don't clip the scrolled child, and don't paint scrollbars/scrollcorner.
1.2488 + // The scrolled frame shouldn't have its own background/border, so we
1.2489 + // can just pass aLists directly.
1.2490 + mOuter->BuildDisplayListForChild(aBuilder, mScrolledFrame,
1.2491 + aDirtyRect, aLists);
1.2492 +
1.2493 +#ifdef MOZ_WIDGET_GONK
1.2494 + // TODO: only layerize the overlay scrollbars if this scrollframe can be
1.2495 + // panned asynchronously. For now just always layerize on B2G because.
1.2496 + // that's where we want the layerized scrollbars
1.2497 + createLayersForScrollbars = true;
1.2498 +#endif
1.2499 + if (addScrollBars) {
1.2500 + // Add overlay scrollbars.
1.2501 + AppendScrollPartsTo(aBuilder, aDirtyRect, aLists, createLayersForScrollbars,
1.2502 + true);
1.2503 + }
1.2504 +
1.2505 + return;
1.2506 + }
1.2507 +
1.2508 + // Now display the scrollbars and scrollcorner. These parts are drawn
1.2509 + // in the border-background layer, on top of our own background and
1.2510 + // borders and underneath borders and backgrounds of later elements
1.2511 + // in the tree.
1.2512 + // Note that this does not apply for overlay scrollbars; those are drawn
1.2513 + // in the positioned-elements layer on top of everything else by the call
1.2514 + // to AppendScrollPartsTo(..., true) further down.
1.2515 + AppendScrollPartsTo(aBuilder, aDirtyRect, aLists, createLayersForScrollbars,
1.2516 + false);
1.2517 +
1.2518 + // Overflow clipping can never clip frames outside our subtree, so there
1.2519 + // is no need to worry about whether we are a moving frame that might clip
1.2520 + // non-moving frames.
1.2521 + // Not all our descendants will be clipped by overflow clipping, but all
1.2522 + // the ones that aren't clipped will be out of flow frames that have already
1.2523 + // had dirty rects saved for them by their parent frames calling
1.2524 + // MarkOutOfFlowChildrenForDisplayList, so it's safe to restrict our
1.2525 + // dirty rect here.
1.2526 + nsRect dirtyRect = aDirtyRect.Intersect(mScrollPort);
1.2527 +
1.2528 + nsRect displayPort;
1.2529 + bool usingDisplayport = false;
1.2530 + if (!aBuilder->IsForEventDelivery()) {
1.2531 + if (!mIsRoot) {
1.2532 + // For a non-root scroll frame, override the value of the display port
1.2533 + // base rect, and possibly create a display port if there isn't one
1.2534 + // already. For root scroll frame, nsLayoutUtils::PaintFrame or
1.2535 + // nsSubDocumentFrame::BuildDisplayList takes care of this.
1.2536 + nsRect displayportBase = dirtyRect;
1.2537 + usingDisplayport = nsLayoutUtils::GetOrMaybeCreateDisplayPort(
1.2538 + *aBuilder, mOuter, displayportBase, &displayPort);
1.2539 + } else {
1.2540 + // For a root frmae, just get the value of the existing of the display
1.2541 + // port, if any.
1.2542 + usingDisplayport = nsLayoutUtils::GetDisplayPort(mOuter->GetContent(), &displayPort);
1.2543 + }
1.2544 +
1.2545 + if (usingDisplayport && DisplayportExceedsMaxTextureSize(mOuter->PresContext(), displayPort)) {
1.2546 + usingDisplayport = false;
1.2547 + }
1.2548 +
1.2549 + // Override the dirty rectangle if the displayport has been set.
1.2550 + if (usingDisplayport) {
1.2551 + dirtyRect = displayPort;
1.2552 + }
1.2553 + }
1.2554 +
1.2555 + if (aBuilder->IsForImageVisibility()) {
1.2556 + // We expand the dirty rect to catch images just outside of the scroll port.
1.2557 + // We use the dirty rect instead of the whole scroll port to prevent
1.2558 + // too much expansion in the presence of very large (bigger than the
1.2559 + // viewport) scroll ports.
1.2560 + dirtyRect = ExpandRect(dirtyRect);
1.2561 + }
1.2562 +
1.2563 + // Since making new layers is expensive, only use nsDisplayScrollLayer
1.2564 + // if the area is scrollable and we're the content process (unless we're on
1.2565 + // B2G, where we support async scrolling for scrollable elements in the
1.2566 + // parent process as well).
1.2567 + // When a displayport is being used, force building of a layer so that
1.2568 + // CompositorParent can always find the scrollable layer for the root content
1.2569 + // document.
1.2570 + // If the element is marked 'scrollgrab', also force building of a layer
1.2571 + // so that APZ can implement scroll grabbing.
1.2572 + mShouldBuildScrollableLayer = usingDisplayport || nsContentUtils::HasScrollgrab(mOuter->GetContent());
1.2573 + bool shouldBuildLayer = false;
1.2574 + if (mShouldBuildScrollableLayer) {
1.2575 + shouldBuildLayer = true;
1.2576 + } else {
1.2577 + shouldBuildLayer =
1.2578 + nsLayoutUtils::WantSubAPZC() &&
1.2579 + WantAsyncScroll() &&
1.2580 + // If we are the root scroll frame for the display root then we don't need a scroll
1.2581 + // info layer to make a RecordFrameMetrics call for us as
1.2582 + // nsDisplayList::PaintForFrame already calls RecordFrameMetrics for us.
1.2583 + (!mIsRoot || aBuilder->RootReferenceFrame()->PresContext() != mOuter->PresContext());
1.2584 + }
1.2585 +
1.2586 + nsDisplayListCollection scrolledContent;
1.2587 + {
1.2588 + // Note that setting the current scroll parent id here means that positioned children
1.2589 + // of this scroll info layer will pick up the scroll info layer as their scroll handoff
1.2590 + // parent. This is intentional because that is what happens for positioned children
1.2591 + // of scroll layers, and we want to maintain consistent behaviour between scroll layers
1.2592 + // and scroll info layers.
1.2593 + nsDisplayListBuilder::AutoCurrentScrollParentIdSetter idSetter(
1.2594 + aBuilder,
1.2595 + shouldBuildLayer && mScrolledFrame->GetContent()
1.2596 + ? nsLayoutUtils::FindOrCreateIDFor(mScrolledFrame->GetContent())
1.2597 + : aBuilder->GetCurrentScrollParentId());
1.2598 + DisplayListClipState::AutoSaveRestore clipState(aBuilder);
1.2599 +
1.2600 + if (usingDisplayport) {
1.2601 + nsRect clip = displayPort + aBuilder->ToReferenceFrame(mOuter);
1.2602 +
1.2603 + // If we are using a display port, then ignore any pre-existing clip
1.2604 + // passed down from our parents, and use only the clip computed here
1.2605 + // based on the display port. The pre-existing clip would just defeat
1.2606 + // the purpose of a display port which is to paint regions that are not
1.2607 + // currently visible so that they can be brought into view asynchronously.
1.2608 + // Notes:
1.2609 + // - The pre-existing clip state will be restored when the
1.2610 + // AutoSaveRestore goes out of scope, so there is no permanent change
1.2611 + // to this clip state.
1.2612 + // - We still set a clip to the scroll port further below where we
1.2613 + // build the scroll wrapper. This doesn't prevent us from painting
1.2614 + // the entire displayport, but it lets the compositor know to
1.2615 + // clip to the scroll port after compositing.
1.2616 + clipState.Clear();
1.2617 +
1.2618 + if (mClipAllDescendants) {
1.2619 + clipState.ClipContentDescendants(clip);
1.2620 + } else {
1.2621 + clipState.ClipContainingBlockDescendants(clip, nullptr);
1.2622 + }
1.2623 + } else {
1.2624 + nsRect clip = mScrollPort + aBuilder->ToReferenceFrame(mOuter);
1.2625 + nscoord radii[8];
1.2626 + bool haveRadii = mOuter->GetPaddingBoxBorderRadii(radii);
1.2627 + // Our override of GetBorderRadii ensures we never have a radius at
1.2628 + // the corners where we have a scrollbar.
1.2629 + if (mClipAllDescendants) {
1.2630 + clipState.ClipContentDescendants(clip, haveRadii ? radii : nullptr);
1.2631 + } else {
1.2632 + clipState.ClipContainingBlockDescendants(clip, haveRadii ? radii : nullptr);
1.2633 + }
1.2634 + }
1.2635 +
1.2636 + mOuter->BuildDisplayListForChild(aBuilder, mScrolledFrame, dirtyRect, scrolledContent);
1.2637 + }
1.2638 +
1.2639 + if (MOZ_UNLIKELY(mOuter->StyleDisplay()->mOverflowClipBox ==
1.2640 + NS_STYLE_OVERFLOW_CLIP_BOX_CONTENT_BOX)) {
1.2641 + // We only clip if there is *scrollable* overflow, to avoid clipping
1.2642 + // *visual* overflow unnecessarily.
1.2643 + nsRect clipRect = mScrollPort + aBuilder->ToReferenceFrame(mOuter);
1.2644 + nsRect so = mScrolledFrame->GetScrollableOverflowRect();
1.2645 + if (clipRect.width != so.width || clipRect.height != so.height ||
1.2646 + so.x < 0 || so.y < 0) {
1.2647 + // The 'scrolledContent' items are clipped to the padding-box at this point.
1.2648 + // Now clip them again to the content-box, except the nsDisplayCaret item
1.2649 + // which we allow to overflow the content-box in various situations --
1.2650 + // see ::ClipItemsExceptCaret.
1.2651 + clipRect.Deflate(mOuter->GetUsedPadding());
1.2652 + DisplayItemClip clip;
1.2653 + clip.SetTo(clipRect);
1.2654 + ::ClipListsExceptCaret(&scrolledContent, aBuilder, mScrolledFrame, clip);
1.2655 + }
1.2656 + }
1.2657 +
1.2658 + if (shouldBuildLayer) {
1.2659 + // ScrollLayerWrapper must always be created because it initializes the
1.2660 + // scroll layer count. The display lists depend on this.
1.2661 + ScrollLayerWrapper wrapper(mOuter, mScrolledFrame);
1.2662 +
1.2663 + if (mShouldBuildScrollableLayer) {
1.2664 + DisplayListClipState::AutoSaveRestore clipState(aBuilder);
1.2665 +
1.2666 + // For root scrollframes in documents where the CSS viewport has been
1.2667 + // modified, the CSS viewport no longer corresponds to what is visible,
1.2668 + // so we don't want to clip the content to it. For root scrollframes
1.2669 + // in documents where the CSS viewport is NOT modified, the mScrollPort
1.2670 + // is the same as the CSS viewport, modulo scrollbars.
1.2671 + if (!(mIsRoot && mOuter->PresContext()->PresShell()->GetIsViewportOverridden())) {
1.2672 + nsRect clip = mScrollPort + aBuilder->ToReferenceFrame(mOuter);
1.2673 + if (mClipAllDescendants) {
1.2674 + clipState.ClipContentDescendants(clip);
1.2675 + } else {
1.2676 + clipState.ClipContainingBlockDescendants(clip);
1.2677 + }
1.2678 + }
1.2679 +
1.2680 + // Once a displayport is set, assume that scrolling needs to be fast
1.2681 + // so create a layer with all the content inside. The compositor
1.2682 + // process will be able to scroll the content asynchronously.
1.2683 + wrapper.WrapListsInPlace(aBuilder, mOuter, scrolledContent);
1.2684 + }
1.2685 +
1.2686 + // In case we are not using displayport or the nsDisplayScrollLayers are
1.2687 + // flattened during visibility computation, we still need to export the
1.2688 + // metadata about this scroll box to the compositor process.
1.2689 + nsDisplayScrollInfoLayer* layerItem = new (aBuilder) nsDisplayScrollInfoLayer(
1.2690 + aBuilder, mScrolledFrame, mOuter);
1.2691 + scrolledContent.BorderBackground()->AppendNewToBottom(layerItem);
1.2692 + }
1.2693 + // Now display overlay scrollbars and the resizer, if we have one.
1.2694 +#ifdef MOZ_WIDGET_GONK
1.2695 + // TODO: only layerize the overlay scrollbars if this scrollframe can be
1.2696 + // panned asynchronously. For now just always layerize on B2G because.
1.2697 + // that's where we want the layerized scrollbars
1.2698 + createLayersForScrollbars = true;
1.2699 +#endif
1.2700 + AppendScrollPartsTo(aBuilder, aDirtyRect, scrolledContent,
1.2701 + createLayersForScrollbars, true);
1.2702 + scrolledContent.MoveTo(aLists);
1.2703 +}
1.2704 +
1.2705 +bool
1.2706 +ScrollFrameHelper::IsRectNearlyVisible(const nsRect& aRect) const
1.2707 +{
1.2708 + // Use the right rect depending on if a display port is set.
1.2709 + nsRect displayPort;
1.2710 + bool usingDisplayport = nsLayoutUtils::GetDisplayPort(mOuter->GetContent(), &displayPort);
1.2711 + return aRect.Intersects(ExpandRect(usingDisplayport ? displayPort : mScrollPort));
1.2712 +}
1.2713 +
1.2714 +static void HandleScrollPref(nsIScrollable *aScrollable, int32_t aOrientation,
1.2715 + uint8_t& aValue)
1.2716 +{
1.2717 + int32_t pref;
1.2718 + aScrollable->GetDefaultScrollbarPreferences(aOrientation, &pref);
1.2719 + switch (pref) {
1.2720 + case nsIScrollable::Scrollbar_Auto:
1.2721 + // leave |aValue| untouched
1.2722 + break;
1.2723 + case nsIScrollable::Scrollbar_Never:
1.2724 + aValue = NS_STYLE_OVERFLOW_HIDDEN;
1.2725 + break;
1.2726 + case nsIScrollable::Scrollbar_Always:
1.2727 + aValue = NS_STYLE_OVERFLOW_SCROLL;
1.2728 + break;
1.2729 + }
1.2730 +}
1.2731 +
1.2732 +ScrollbarStyles
1.2733 +ScrollFrameHelper::GetScrollbarStylesFromFrame() const
1.2734 +{
1.2735 + nsPresContext* presContext = mOuter->PresContext();
1.2736 + if (!presContext->IsDynamic() &&
1.2737 + !(mIsRoot && presContext->HasPaginatedScrolling())) {
1.2738 + return ScrollbarStyles(NS_STYLE_OVERFLOW_HIDDEN, NS_STYLE_OVERFLOW_HIDDEN);
1.2739 + }
1.2740 +
1.2741 + if (!mIsRoot) {
1.2742 + const nsStyleDisplay* disp = mOuter->StyleDisplay();
1.2743 + return ScrollbarStyles(disp->mOverflowX, disp->mOverflowY);
1.2744 + }
1.2745 +
1.2746 + ScrollbarStyles result = presContext->GetViewportOverflowOverride();
1.2747 + nsCOMPtr<nsISupports> container = presContext->GetContainerWeak();
1.2748 + nsCOMPtr<nsIScrollable> scrollable = do_QueryInterface(container);
1.2749 + if (scrollable) {
1.2750 + HandleScrollPref(scrollable, nsIScrollable::ScrollOrientation_X,
1.2751 + result.mHorizontal);
1.2752 + HandleScrollPref(scrollable, nsIScrollable::ScrollOrientation_Y,
1.2753 + result.mVertical);
1.2754 + }
1.2755 + return result;
1.2756 +}
1.2757 +
1.2758 +nsRect
1.2759 +ScrollFrameHelper::GetScrollRange() const
1.2760 +{
1.2761 + return GetScrollRange(mScrollPort.width, mScrollPort.height);
1.2762 +}
1.2763 +
1.2764 +nsRect
1.2765 +ScrollFrameHelper::GetScrollRange(nscoord aWidth, nscoord aHeight) const
1.2766 +{
1.2767 + nsRect range = GetScrolledRect();
1.2768 + range.width = std::max(range.width - aWidth, 0);
1.2769 + range.height = std::max(range.height - aHeight, 0);
1.2770 + return range;
1.2771 +}
1.2772 +
1.2773 +nsRect
1.2774 +ScrollFrameHelper::GetScrollRangeForClamping() const
1.2775 +{
1.2776 + if (!ShouldClampScrollPosition()) {
1.2777 + return nsRect(nscoord_MIN/2, nscoord_MIN/2,
1.2778 + nscoord_MAX - nscoord_MIN/2, nscoord_MAX - nscoord_MIN/2);
1.2779 + }
1.2780 + nsSize scrollPortSize = GetScrollPositionClampingScrollPortSize();
1.2781 + return GetScrollRange(scrollPortSize.width, scrollPortSize.height);
1.2782 +}
1.2783 +
1.2784 +nsSize
1.2785 +ScrollFrameHelper::GetScrollPositionClampingScrollPortSize() const
1.2786 +{
1.2787 + nsIPresShell* presShell = mOuter->PresContext()->PresShell();
1.2788 + if (mIsRoot && presShell->IsScrollPositionClampingScrollPortSizeSet()) {
1.2789 + return presShell->GetScrollPositionClampingScrollPortSize();
1.2790 + }
1.2791 + return mScrollPort.Size();
1.2792 +}
1.2793 +
1.2794 +gfxSize
1.2795 +ScrollFrameHelper::GetResolution() const
1.2796 +{
1.2797 + return mResolution;
1.2798 +}
1.2799 +
1.2800 +void
1.2801 +ScrollFrameHelper::SetResolution(const gfxSize& aResolution)
1.2802 +{
1.2803 + mResolution = aResolution;
1.2804 + mIsResolutionSet = true;
1.2805 +}
1.2806 +
1.2807 +static void
1.2808 +AdjustForWholeDelta(int32_t aDelta, nscoord* aCoord)
1.2809 +{
1.2810 + if (aDelta < 0) {
1.2811 + *aCoord = nscoord_MIN;
1.2812 + } else if (aDelta > 0) {
1.2813 + *aCoord = nscoord_MAX;
1.2814 + }
1.2815 +}
1.2816 +
1.2817 +/**
1.2818 + * Calculate lower/upper scrollBy range in given direction.
1.2819 + * @param aDelta specifies scrollBy direction, if 0 then range will be 0 size
1.2820 + * @param aPos desired destination in AppUnits
1.2821 + * @param aNeg/PosTolerance defines relative range distance
1.2822 + * below and above of aPos point
1.2823 + * @param aMultiplier used for conversion of tolerance into appUnis
1.2824 + */
1.2825 +static void
1.2826 +CalcRangeForScrollBy(int32_t aDelta, nscoord aPos,
1.2827 + float aNegTolerance,
1.2828 + float aPosTolerance,
1.2829 + nscoord aMultiplier,
1.2830 + nscoord* aLower, nscoord* aUpper)
1.2831 +{
1.2832 + if (!aDelta) {
1.2833 + *aLower = *aUpper = aPos;
1.2834 + return;
1.2835 + }
1.2836 + *aLower = aPos - NSToCoordRound(aMultiplier * (aDelta > 0 ? aNegTolerance : aPosTolerance));
1.2837 + *aUpper = aPos + NSToCoordRound(aMultiplier * (aDelta > 0 ? aPosTolerance : aNegTolerance));
1.2838 +}
1.2839 +
1.2840 +void
1.2841 +ScrollFrameHelper::ScrollBy(nsIntPoint aDelta,
1.2842 + nsIScrollableFrame::ScrollUnit aUnit,
1.2843 + nsIScrollableFrame::ScrollMode aMode,
1.2844 + nsIntPoint* aOverflow,
1.2845 + nsIAtom *aOrigin)
1.2846 +{
1.2847 + nsSize deltaMultiplier;
1.2848 + float negativeTolerance;
1.2849 + float positiveTolerance;
1.2850 + if (!aOrigin){
1.2851 + aOrigin = nsGkAtoms::other;
1.2852 + }
1.2853 + bool isGenericOrigin = (aOrigin == nsGkAtoms::other);
1.2854 + switch (aUnit) {
1.2855 + case nsIScrollableFrame::DEVICE_PIXELS: {
1.2856 + nscoord appUnitsPerDevPixel =
1.2857 + mOuter->PresContext()->AppUnitsPerDevPixel();
1.2858 + deltaMultiplier = nsSize(appUnitsPerDevPixel, appUnitsPerDevPixel);
1.2859 + if (isGenericOrigin){
1.2860 + aOrigin = nsGkAtoms::pixels;
1.2861 + }
1.2862 + negativeTolerance = positiveTolerance = 0.5f;
1.2863 + break;
1.2864 + }
1.2865 + case nsIScrollableFrame::LINES: {
1.2866 + deltaMultiplier = GetLineScrollAmount();
1.2867 + if (isGenericOrigin){
1.2868 + aOrigin = nsGkAtoms::lines;
1.2869 + }
1.2870 + negativeTolerance = positiveTolerance = 0.1f;
1.2871 + break;
1.2872 + }
1.2873 + case nsIScrollableFrame::PAGES: {
1.2874 + deltaMultiplier = GetPageScrollAmount();
1.2875 + if (isGenericOrigin){
1.2876 + aOrigin = nsGkAtoms::pages;
1.2877 + }
1.2878 + negativeTolerance = 0.05f;
1.2879 + positiveTolerance = 0;
1.2880 + break;
1.2881 + }
1.2882 + case nsIScrollableFrame::WHOLE: {
1.2883 + nsPoint pos = GetScrollPosition();
1.2884 + AdjustForWholeDelta(aDelta.x, &pos.x);
1.2885 + AdjustForWholeDelta(aDelta.y, &pos.y);
1.2886 + ScrollTo(pos, aMode);
1.2887 + // 'this' might be destroyed here
1.2888 + if (aOverflow) {
1.2889 + *aOverflow = nsIntPoint(0, 0);
1.2890 + }
1.2891 + return;
1.2892 + }
1.2893 + default:
1.2894 + NS_ERROR("Invalid scroll mode");
1.2895 + return;
1.2896 + }
1.2897 +
1.2898 + nsPoint newPos = mDestination +
1.2899 + nsPoint(aDelta.x*deltaMultiplier.width, aDelta.y*deltaMultiplier.height);
1.2900 + // Calculate desired range values.
1.2901 + nscoord rangeLowerX, rangeUpperX, rangeLowerY, rangeUpperY;
1.2902 + CalcRangeForScrollBy(aDelta.x, newPos.x, negativeTolerance, positiveTolerance,
1.2903 + deltaMultiplier.width, &rangeLowerX, &rangeUpperX);
1.2904 + CalcRangeForScrollBy(aDelta.y, newPos.y, negativeTolerance, positiveTolerance,
1.2905 + deltaMultiplier.height, &rangeLowerY, &rangeUpperY);
1.2906 + nsRect range(rangeLowerX,
1.2907 + rangeLowerY,
1.2908 + rangeUpperX - rangeLowerX,
1.2909 + rangeUpperY - rangeLowerY);
1.2910 + nsWeakFrame weakFrame(mOuter);
1.2911 + ScrollToWithOrigin(newPos, aMode, aOrigin, &range);
1.2912 + if (!weakFrame.IsAlive()) {
1.2913 + return;
1.2914 + }
1.2915 +
1.2916 + if (aOverflow) {
1.2917 + nsPoint clampAmount = newPos - mDestination;
1.2918 + float appUnitsPerDevPixel = mOuter->PresContext()->AppUnitsPerDevPixel();
1.2919 + *aOverflow = nsIntPoint(
1.2920 + NSAppUnitsToIntPixels(clampAmount.x, appUnitsPerDevPixel),
1.2921 + NSAppUnitsToIntPixels(clampAmount.y, appUnitsPerDevPixel));
1.2922 + }
1.2923 +}
1.2924 +
1.2925 +nsSize
1.2926 +ScrollFrameHelper::GetLineScrollAmount() const
1.2927 +{
1.2928 + nsRefPtr<nsFontMetrics> fm;
1.2929 + nsLayoutUtils::GetFontMetricsForFrame(mOuter, getter_AddRefs(fm),
1.2930 + nsLayoutUtils::FontSizeInflationFor(mOuter));
1.2931 + NS_ASSERTION(fm, "FontMetrics is null, assuming fontHeight == 1 appunit");
1.2932 + static nscoord sMinLineScrollAmountInPixels = -1;
1.2933 + if (sMinLineScrollAmountInPixels < 0) {
1.2934 + Preferences::AddIntVarCache(&sMinLineScrollAmountInPixels,
1.2935 + "mousewheel.min_line_scroll_amount", 1);
1.2936 + }
1.2937 + int32_t appUnitsPerDevPixel = mOuter->PresContext()->AppUnitsPerDevPixel();
1.2938 + nscoord minScrollAmountInAppUnits =
1.2939 + std::max(1, sMinLineScrollAmountInPixels) * appUnitsPerDevPixel;
1.2940 + nscoord horizontalAmount = fm ? fm->AveCharWidth() : 0;
1.2941 + nscoord verticalAmount = fm ? fm->MaxHeight() : 0;
1.2942 + return nsSize(std::max(horizontalAmount, minScrollAmountInAppUnits),
1.2943 + std::max(verticalAmount, minScrollAmountInAppUnits));
1.2944 +}
1.2945 +
1.2946 +/**
1.2947 + * Compute the scrollport size excluding any fixed-pos headers and
1.2948 + * footers. A header or footer is an box that spans that entire width
1.2949 + * of the viewport and touches the top (or bottom, respectively) of the
1.2950 + * viewport. We also want to consider fixed elements that stack or overlap
1.2951 + * to effectively create a larger header or footer. Headers and footers that
1.2952 + * cover more than a third of the the viewport are ignored since they
1.2953 + * probably aren't true headers and footers and we don't want to restrict
1.2954 + * scrolling too much in such cases. This is a bit conservative --- some
1.2955 + * pages use elements as headers or footers that don't span the entire width
1.2956 + * of the viewport --- but it should be a good start.
1.2957 + */
1.2958 +struct TopAndBottom
1.2959 +{
1.2960 + TopAndBottom(nscoord aTop, nscoord aBottom) : top(aTop), bottom(aBottom) {}
1.2961 +
1.2962 + nscoord top, bottom;
1.2963 +};
1.2964 +struct TopComparator
1.2965 +{
1.2966 + bool Equals(const TopAndBottom& A, const TopAndBottom& B) const {
1.2967 + return A.top == B.top;
1.2968 + }
1.2969 + bool LessThan(const TopAndBottom& A, const TopAndBottom& B) const {
1.2970 + return A.top < B.top;
1.2971 + }
1.2972 +};
1.2973 +struct ReverseBottomComparator
1.2974 +{
1.2975 + bool Equals(const TopAndBottom& A, const TopAndBottom& B) const {
1.2976 + return A.bottom == B.bottom;
1.2977 + }
1.2978 + bool LessThan(const TopAndBottom& A, const TopAndBottom& B) const {
1.2979 + return A.bottom > B.bottom;
1.2980 + }
1.2981 +};
1.2982 +static nsSize
1.2983 +GetScrollPortSizeExcludingHeadersAndFooters(nsIFrame* aViewportFrame,
1.2984 + const nsRect& aScrollPort)
1.2985 +{
1.2986 + nsTArray<TopAndBottom> list;
1.2987 + nsFrameList fixedFrames = aViewportFrame->GetChildList(nsIFrame::kFixedList);
1.2988 + for (nsFrameList::Enumerator iterator(fixedFrames); !iterator.AtEnd();
1.2989 + iterator.Next()) {
1.2990 + nsIFrame* f = iterator.get();
1.2991 + nsRect r = f->GetRect().Intersect(aScrollPort);
1.2992 + if (r.x == 0 && r.width == aScrollPort.width &&
1.2993 + r.height <= aScrollPort.height/3) {
1.2994 + list.AppendElement(TopAndBottom(r.y, r.YMost()));
1.2995 + }
1.2996 + }
1.2997 +
1.2998 + list.Sort(TopComparator());
1.2999 + nscoord headerBottom = 0;
1.3000 + for (uint32_t i = 0; i < list.Length(); ++i) {
1.3001 + if (list[i].top <= headerBottom) {
1.3002 + headerBottom = std::max(headerBottom, list[i].bottom);
1.3003 + }
1.3004 + }
1.3005 +
1.3006 + list.Sort(ReverseBottomComparator());
1.3007 + nscoord footerTop = aScrollPort.height;
1.3008 + for (uint32_t i = 0; i < list.Length(); ++i) {
1.3009 + if (list[i].bottom >= footerTop) {
1.3010 + footerTop = std::min(footerTop, list[i].top);
1.3011 + }
1.3012 + }
1.3013 +
1.3014 + headerBottom = std::min(aScrollPort.height/3, headerBottom);
1.3015 + footerTop = std::max(aScrollPort.height - aScrollPort.height/3, footerTop);
1.3016 +
1.3017 + return nsSize(aScrollPort.width, footerTop - headerBottom);
1.3018 +}
1.3019 +
1.3020 +nsSize
1.3021 +ScrollFrameHelper::GetPageScrollAmount() const
1.3022 +{
1.3023 + nsSize lineScrollAmount = GetLineScrollAmount();
1.3024 + nsSize effectiveScrollPortSize;
1.3025 + if (mIsRoot) {
1.3026 + // Reduce effective scrollport height by the height of any fixed-pos
1.3027 + // headers or footers
1.3028 + nsIFrame* root = mOuter->PresContext()->PresShell()->GetRootFrame();
1.3029 + effectiveScrollPortSize =
1.3030 + GetScrollPortSizeExcludingHeadersAndFooters(root, mScrollPort);
1.3031 + } else {
1.3032 + effectiveScrollPortSize = mScrollPort.Size();
1.3033 + }
1.3034 + // The page increment is the size of the page, minus the smaller of
1.3035 + // 10% of the size or 2 lines.
1.3036 + return nsSize(
1.3037 + effectiveScrollPortSize.width -
1.3038 + std::min(effectiveScrollPortSize.width/10, 2*lineScrollAmount.width),
1.3039 + effectiveScrollPortSize.height -
1.3040 + std::min(effectiveScrollPortSize.height/10, 2*lineScrollAmount.height));
1.3041 +}
1.3042 +
1.3043 + /**
1.3044 + * this code is resposible for restoring the scroll position back to some
1.3045 + * saved position. if the user has not moved the scroll position manually
1.3046 + * we keep scrolling down until we get to our original position. keep in
1.3047 + * mind that content could incrementally be coming in. we only want to stop
1.3048 + * when we reach our new position.
1.3049 + */
1.3050 +void
1.3051 +ScrollFrameHelper::ScrollToRestoredPosition()
1.3052 +{
1.3053 + if (mRestorePos.y == -1 || mLastPos.x == -1 || mLastPos.y == -1) {
1.3054 + return;
1.3055 + }
1.3056 + // make sure our scroll position did not change for where we last put
1.3057 + // it. if it does then the user must have moved it, and we no longer
1.3058 + // need to restore.
1.3059 + //
1.3060 + // In the RTL case, we check whether the scroll position changed using the
1.3061 + // logical scroll position, but we scroll to the physical scroll position in
1.3062 + // all cases
1.3063 +
1.3064 + // if we didn't move, we still need to restore
1.3065 + if (GetLogicalScrollPosition() == mLastPos) {
1.3066 + // if our desired position is different to the scroll position, scroll.
1.3067 + // remember that we could be incrementally loading so we may enter
1.3068 + // and scroll many times.
1.3069 + if (mRestorePos != mLastPos /* GetLogicalScrollPosition() */) {
1.3070 + nsPoint scrollToPos = mRestorePos;
1.3071 + if (!IsLTR())
1.3072 + // convert from logical to physical scroll position
1.3073 + scrollToPos.x = mScrollPort.x -
1.3074 + (mScrollPort.XMost() - scrollToPos.x - mScrolledFrame->GetRect().width);
1.3075 + nsWeakFrame weakFrame(mOuter);
1.3076 + ScrollTo(scrollToPos, nsIScrollableFrame::INSTANT);
1.3077 + if (!weakFrame.IsAlive()) {
1.3078 + return;
1.3079 + }
1.3080 + // Re-get the scroll position, it might not be exactly equal to
1.3081 + // mRestorePos due to rounding and clamping.
1.3082 + mLastPos = GetLogicalScrollPosition();
1.3083 + } else {
1.3084 + // if we reached the position then stop
1.3085 + mRestorePos.y = -1;
1.3086 + mLastPos.x = -1;
1.3087 + mLastPos.y = -1;
1.3088 + }
1.3089 + } else {
1.3090 + // user moved the position, so we won't need to restore
1.3091 + mLastPos.x = -1;
1.3092 + mLastPos.y = -1;
1.3093 + }
1.3094 +}
1.3095 +
1.3096 +nsresult
1.3097 +ScrollFrameHelper::FireScrollPortEvent()
1.3098 +{
1.3099 + mAsyncScrollPortEvent.Forget();
1.3100 +
1.3101 + // Keep this in sync with PostOverflowEvent().
1.3102 + nsSize scrollportSize = mScrollPort.Size();
1.3103 + nsSize childSize = GetScrolledRect().Size();
1.3104 +
1.3105 + bool newVerticalOverflow = childSize.height > scrollportSize.height;
1.3106 + bool vertChanged = mVerticalOverflow != newVerticalOverflow;
1.3107 +
1.3108 + bool newHorizontalOverflow = childSize.width > scrollportSize.width;
1.3109 + bool horizChanged = mHorizontalOverflow != newHorizontalOverflow;
1.3110 +
1.3111 + if (!vertChanged && !horizChanged) {
1.3112 + return NS_OK;
1.3113 + }
1.3114 +
1.3115 + // If both either overflowed or underflowed then we dispatch only one
1.3116 + // DOM event.
1.3117 + bool both = vertChanged && horizChanged &&
1.3118 + newVerticalOverflow == newHorizontalOverflow;
1.3119 + InternalScrollPortEvent::orientType orient;
1.3120 + if (both) {
1.3121 + orient = InternalScrollPortEvent::both;
1.3122 + mHorizontalOverflow = newHorizontalOverflow;
1.3123 + mVerticalOverflow = newVerticalOverflow;
1.3124 + }
1.3125 + else if (vertChanged) {
1.3126 + orient = InternalScrollPortEvent::vertical;
1.3127 + mVerticalOverflow = newVerticalOverflow;
1.3128 + if (horizChanged) {
1.3129 + // We need to dispatch a separate horizontal DOM event. Do that the next
1.3130 + // time around since dispatching the vertical DOM event might destroy
1.3131 + // the frame.
1.3132 + PostOverflowEvent();
1.3133 + }
1.3134 + }
1.3135 + else {
1.3136 + orient = InternalScrollPortEvent::horizontal;
1.3137 + mHorizontalOverflow = newHorizontalOverflow;
1.3138 + }
1.3139 +
1.3140 + InternalScrollPortEvent event(true,
1.3141 + (orient == InternalScrollPortEvent::horizontal ? mHorizontalOverflow :
1.3142 + mVerticalOverflow) ?
1.3143 + NS_SCROLLPORT_OVERFLOW : NS_SCROLLPORT_UNDERFLOW, nullptr);
1.3144 + event.orient = orient;
1.3145 + return EventDispatcher::Dispatch(mOuter->GetContent(),
1.3146 + mOuter->PresContext(), &event);
1.3147 +}
1.3148 +
1.3149 +void
1.3150 +ScrollFrameHelper::ReloadChildFrames()
1.3151 +{
1.3152 + mScrolledFrame = nullptr;
1.3153 + mHScrollbarBox = nullptr;
1.3154 + mVScrollbarBox = nullptr;
1.3155 + mScrollCornerBox = nullptr;
1.3156 + mResizerBox = nullptr;
1.3157 +
1.3158 + nsIFrame* frame = mOuter->GetFirstPrincipalChild();
1.3159 + while (frame) {
1.3160 + nsIContent* content = frame->GetContent();
1.3161 + if (content == mOuter->GetContent()) {
1.3162 + NS_ASSERTION(!mScrolledFrame, "Already found the scrolled frame");
1.3163 + mScrolledFrame = frame;
1.3164 + } else {
1.3165 + nsAutoString value;
1.3166 + content->GetAttr(kNameSpaceID_None, nsGkAtoms::orient, value);
1.3167 + if (!value.IsEmpty()) {
1.3168 + // probably a scrollbar then
1.3169 + if (value.LowerCaseEqualsLiteral("horizontal")) {
1.3170 + NS_ASSERTION(!mHScrollbarBox, "Found multiple horizontal scrollbars?");
1.3171 + mHScrollbarBox = frame;
1.3172 + } else {
1.3173 + NS_ASSERTION(!mVScrollbarBox, "Found multiple vertical scrollbars?");
1.3174 + mVScrollbarBox = frame;
1.3175 + }
1.3176 + } else if (content->Tag() == nsGkAtoms::resizer) {
1.3177 + NS_ASSERTION(!mResizerBox, "Found multiple resizers");
1.3178 + mResizerBox = frame;
1.3179 + } else if (content->Tag() == nsGkAtoms::scrollcorner) {
1.3180 + // probably a scrollcorner
1.3181 + NS_ASSERTION(!mScrollCornerBox, "Found multiple scrollcorners");
1.3182 + mScrollCornerBox = frame;
1.3183 + }
1.3184 + }
1.3185 +
1.3186 + frame = frame->GetNextSibling();
1.3187 + }
1.3188 +}
1.3189 +
1.3190 +nsresult
1.3191 +ScrollFrameHelper::CreateAnonymousContent(
1.3192 + nsTArray<nsIAnonymousContentCreator::ContentInfo>& aElements)
1.3193 +{
1.3194 + nsPresContext* presContext = mOuter->PresContext();
1.3195 + nsIFrame* parent = mOuter->GetParent();
1.3196 +
1.3197 + // Don't create scrollbars if we're an SVG document being used as an image,
1.3198 + // or if we're printing/print previewing.
1.3199 + // (In the printing case, we allow scrollbars if this is the child of the
1.3200 + // viewport & paginated scrolling is enabled, because then we must be the
1.3201 + // scroll frame for the print preview window, & that does need scrollbars.)
1.3202 + if (presContext->Document()->IsBeingUsedAsImage() ||
1.3203 + (!presContext->IsDynamic() &&
1.3204 + !(mIsRoot && presContext->HasPaginatedScrolling()))) {
1.3205 + mNeverHasVerticalScrollbar = mNeverHasHorizontalScrollbar = true;
1.3206 + return NS_OK;
1.3207 + }
1.3208 +
1.3209 + // Check if the frame is resizable.
1.3210 + int8_t resizeStyle = mOuter->StyleDisplay()->mResize;
1.3211 + bool isResizable = resizeStyle != NS_STYLE_RESIZE_NONE;
1.3212 +
1.3213 + nsIScrollableFrame *scrollable = do_QueryFrame(mOuter);
1.3214 +
1.3215 + // If we're the scrollframe for the root, then we want to construct
1.3216 + // our scrollbar frames no matter what. That way later dynamic
1.3217 + // changes to propagated overflow styles will show or hide
1.3218 + // scrollbars on the viewport without requiring frame reconstruction
1.3219 + // of the viewport (good!).
1.3220 + bool canHaveHorizontal;
1.3221 + bool canHaveVertical;
1.3222 + if (!mIsRoot) {
1.3223 + ScrollbarStyles styles = scrollable->GetScrollbarStyles();
1.3224 + canHaveHorizontal = styles.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN;
1.3225 + canHaveVertical = styles.mVertical != NS_STYLE_OVERFLOW_HIDDEN;
1.3226 + if (!canHaveHorizontal && !canHaveVertical && !isResizable) {
1.3227 + // Nothing to do.
1.3228 + return NS_OK;
1.3229 + }
1.3230 + } else {
1.3231 + canHaveHorizontal = true;
1.3232 + canHaveVertical = true;
1.3233 + }
1.3234 +
1.3235 + // The anonymous <div> used by <inputs> never gets scrollbars.
1.3236 + nsITextControlFrame* textFrame = do_QueryFrame(parent);
1.3237 + if (textFrame) {
1.3238 + // Make sure we are not a text area.
1.3239 + nsCOMPtr<nsIDOMHTMLTextAreaElement> textAreaElement(do_QueryInterface(parent->GetContent()));
1.3240 + if (!textAreaElement) {
1.3241 + mNeverHasVerticalScrollbar = mNeverHasHorizontalScrollbar = true;
1.3242 + return NS_OK;
1.3243 + }
1.3244 + }
1.3245 +
1.3246 + nsNodeInfoManager *nodeInfoManager =
1.3247 + presContext->Document()->NodeInfoManager();
1.3248 + nsCOMPtr<nsINodeInfo> nodeInfo;
1.3249 + nodeInfo = nodeInfoManager->GetNodeInfo(nsGkAtoms::scrollbar, nullptr,
1.3250 + kNameSpaceID_XUL,
1.3251 + nsIDOMNode::ELEMENT_NODE);
1.3252 + NS_ENSURE_TRUE(nodeInfo, NS_ERROR_OUT_OF_MEMORY);
1.3253 +
1.3254 + if (canHaveHorizontal) {
1.3255 + nsCOMPtr<nsINodeInfo> ni = nodeInfo;
1.3256 + NS_TrustedNewXULElement(getter_AddRefs(mHScrollbarContent), ni.forget());
1.3257 + mHScrollbarContent->SetAttr(kNameSpaceID_None, nsGkAtoms::orient,
1.3258 + NS_LITERAL_STRING("horizontal"), false);
1.3259 + mHScrollbarContent->SetAttr(kNameSpaceID_None, nsGkAtoms::clickthrough,
1.3260 + NS_LITERAL_STRING("always"), false);
1.3261 + if (mIsRoot) {
1.3262 + mHScrollbarContent->SetAttr(kNameSpaceID_None, nsGkAtoms::root_,
1.3263 + NS_LITERAL_STRING("true"), false);
1.3264 + }
1.3265 + if (!aElements.AppendElement(mHScrollbarContent))
1.3266 + return NS_ERROR_OUT_OF_MEMORY;
1.3267 + }
1.3268 +
1.3269 + if (canHaveVertical) {
1.3270 + nsCOMPtr<nsINodeInfo> ni = nodeInfo;
1.3271 + NS_TrustedNewXULElement(getter_AddRefs(mVScrollbarContent), ni.forget());
1.3272 + mVScrollbarContent->SetAttr(kNameSpaceID_None, nsGkAtoms::orient,
1.3273 + NS_LITERAL_STRING("vertical"), false);
1.3274 + mVScrollbarContent->SetAttr(kNameSpaceID_None, nsGkAtoms::clickthrough,
1.3275 + NS_LITERAL_STRING("always"), false);
1.3276 + if (mIsRoot) {
1.3277 + mVScrollbarContent->SetAttr(kNameSpaceID_None, nsGkAtoms::root_,
1.3278 + NS_LITERAL_STRING("true"), false);
1.3279 + }
1.3280 + if (!aElements.AppendElement(mVScrollbarContent))
1.3281 + return NS_ERROR_OUT_OF_MEMORY;
1.3282 + }
1.3283 +
1.3284 + if (isResizable) {
1.3285 + nsCOMPtr<nsINodeInfo> nodeInfo;
1.3286 + nodeInfo = nodeInfoManager->GetNodeInfo(nsGkAtoms::resizer, nullptr,
1.3287 + kNameSpaceID_XUL,
1.3288 + nsIDOMNode::ELEMENT_NODE);
1.3289 + NS_ENSURE_TRUE(nodeInfo, NS_ERROR_OUT_OF_MEMORY);
1.3290 +
1.3291 + NS_TrustedNewXULElement(getter_AddRefs(mResizerContent), nodeInfo.forget());
1.3292 +
1.3293 + nsAutoString dir;
1.3294 + switch (resizeStyle) {
1.3295 + case NS_STYLE_RESIZE_HORIZONTAL:
1.3296 + if (IsScrollbarOnRight()) {
1.3297 + dir.AssignLiteral("right");
1.3298 + }
1.3299 + else {
1.3300 + dir.AssignLiteral("left");
1.3301 + }
1.3302 + break;
1.3303 + case NS_STYLE_RESIZE_VERTICAL:
1.3304 + dir.AssignLiteral("bottom");
1.3305 + break;
1.3306 + case NS_STYLE_RESIZE_BOTH:
1.3307 + dir.AssignLiteral("bottomend");
1.3308 + break;
1.3309 + default:
1.3310 + NS_WARNING("only resizable types should have resizers");
1.3311 + }
1.3312 + mResizerContent->SetAttr(kNameSpaceID_None, nsGkAtoms::dir, dir, false);
1.3313 +
1.3314 + if (mIsRoot) {
1.3315 + nsIContent* browserRoot = GetBrowserRoot(mOuter->GetContent());
1.3316 + mCollapsedResizer = !(browserRoot &&
1.3317 + browserRoot->HasAttr(kNameSpaceID_None, nsGkAtoms::showresizer));
1.3318 + }
1.3319 + else {
1.3320 + mResizerContent->SetAttr(kNameSpaceID_None, nsGkAtoms::element,
1.3321 + NS_LITERAL_STRING("_parent"), false);
1.3322 + }
1.3323 +
1.3324 + mResizerContent->SetAttr(kNameSpaceID_None, nsGkAtoms::clickthrough,
1.3325 + NS_LITERAL_STRING("always"), false);
1.3326 +
1.3327 + if (!aElements.AppendElement(mResizerContent))
1.3328 + return NS_ERROR_OUT_OF_MEMORY;
1.3329 + }
1.3330 +
1.3331 + if (canHaveHorizontal && canHaveVertical) {
1.3332 + nodeInfo = nodeInfoManager->GetNodeInfo(nsGkAtoms::scrollcorner, nullptr,
1.3333 + kNameSpaceID_XUL,
1.3334 + nsIDOMNode::ELEMENT_NODE);
1.3335 + NS_TrustedNewXULElement(getter_AddRefs(mScrollCornerContent), nodeInfo.forget());
1.3336 + if (!aElements.AppendElement(mScrollCornerContent))
1.3337 + return NS_ERROR_OUT_OF_MEMORY;
1.3338 + }
1.3339 +
1.3340 + return NS_OK;
1.3341 +}
1.3342 +
1.3343 +void
1.3344 +ScrollFrameHelper::AppendAnonymousContentTo(nsBaseContentList& aElements,
1.3345 + uint32_t aFilter)
1.3346 +{
1.3347 + aElements.MaybeAppendElement(mHScrollbarContent);
1.3348 + aElements.MaybeAppendElement(mVScrollbarContent);
1.3349 + aElements.MaybeAppendElement(mScrollCornerContent);
1.3350 + aElements.MaybeAppendElement(mResizerContent);
1.3351 +}
1.3352 +
1.3353 +void
1.3354 +ScrollFrameHelper::Destroy()
1.3355 +{
1.3356 + if (mScrollbarActivity) {
1.3357 + mScrollbarActivity->Destroy();
1.3358 + mScrollbarActivity = nullptr;
1.3359 + }
1.3360 +
1.3361 + // Unbind any content created in CreateAnonymousContent from the tree
1.3362 + nsContentUtils::DestroyAnonymousContent(&mHScrollbarContent);
1.3363 + nsContentUtils::DestroyAnonymousContent(&mVScrollbarContent);
1.3364 + nsContentUtils::DestroyAnonymousContent(&mScrollCornerContent);
1.3365 + nsContentUtils::DestroyAnonymousContent(&mResizerContent);
1.3366 +
1.3367 + if (mPostedReflowCallback) {
1.3368 + mOuter->PresContext()->PresShell()->CancelReflowCallback(this);
1.3369 + mPostedReflowCallback = false;
1.3370 + }
1.3371 +}
1.3372 +
1.3373 +/**
1.3374 + * Called when we want to update the scrollbar position, either because scrolling happened
1.3375 + * or the user moved the scrollbar position and we need to undo that (e.g., when the user
1.3376 + * clicks to scroll and we're using smooth scrolling, so we need to put the thumb back
1.3377 + * to its initial position for the start of the smooth sequence).
1.3378 + */
1.3379 +void
1.3380 +ScrollFrameHelper::UpdateScrollbarPosition()
1.3381 +{
1.3382 + nsWeakFrame weakFrame(mOuter);
1.3383 + mFrameIsUpdatingScrollbar = true;
1.3384 +
1.3385 + nsPoint pt = GetScrollPosition();
1.3386 + if (mVScrollbarBox) {
1.3387 + SetCoordAttribute(mVScrollbarBox->GetContent(), nsGkAtoms::curpos,
1.3388 + pt.y - GetScrolledRect().y);
1.3389 + if (!weakFrame.IsAlive()) {
1.3390 + return;
1.3391 + }
1.3392 + }
1.3393 + if (mHScrollbarBox) {
1.3394 + SetCoordAttribute(mHScrollbarBox->GetContent(), nsGkAtoms::curpos,
1.3395 + pt.x - GetScrolledRect().x);
1.3396 + if (!weakFrame.IsAlive()) {
1.3397 + return;
1.3398 + }
1.3399 + }
1.3400 +
1.3401 + mFrameIsUpdatingScrollbar = false;
1.3402 +}
1.3403 +
1.3404 +void ScrollFrameHelper::CurPosAttributeChanged(nsIContent* aContent)
1.3405 +{
1.3406 + NS_ASSERTION(aContent, "aContent must not be null");
1.3407 + NS_ASSERTION((mHScrollbarBox && mHScrollbarBox->GetContent() == aContent) ||
1.3408 + (mVScrollbarBox && mVScrollbarBox->GetContent() == aContent),
1.3409 + "unexpected child");
1.3410 +
1.3411 + // Attribute changes on the scrollbars happen in one of three ways:
1.3412 + // 1) The scrollbar changed the attribute in response to some user event
1.3413 + // 2) We changed the attribute in response to a ScrollPositionDidChange
1.3414 + // callback from the scrolling view
1.3415 + // 3) We changed the attribute to adjust the scrollbars for the start
1.3416 + // of a smooth scroll operation
1.3417 + //
1.3418 + // In cases 2 and 3 we do not need to scroll because we're just
1.3419 + // updating our scrollbar.
1.3420 + if (mFrameIsUpdatingScrollbar)
1.3421 + return;
1.3422 +
1.3423 + nsRect scrolledRect = GetScrolledRect();
1.3424 +
1.3425 + nsPoint current = GetScrollPosition() - scrolledRect.TopLeft();
1.3426 + nsPoint dest;
1.3427 + nsRect allowedRange;
1.3428 + dest.x = GetCoordAttribute(mHScrollbarBox, nsGkAtoms::curpos, current.x,
1.3429 + &allowedRange.x, &allowedRange.width);
1.3430 + dest.y = GetCoordAttribute(mVScrollbarBox, nsGkAtoms::curpos, current.y,
1.3431 + &allowedRange.y, &allowedRange.height);
1.3432 + current += scrolledRect.TopLeft();
1.3433 + dest += scrolledRect.TopLeft();
1.3434 + allowedRange += scrolledRect.TopLeft();
1.3435 +
1.3436 + // Don't try to scroll if we're already at an acceptable place.
1.3437 + // Don't call Contains here since Contains returns false when the point is
1.3438 + // on the bottom or right edge of the rectangle.
1.3439 + if (allowedRange.ClampPoint(current) == current) {
1.3440 + return;
1.3441 + }
1.3442 +
1.3443 + if (mScrollbarActivity) {
1.3444 + nsRefPtr<ScrollbarActivity> scrollbarActivity(mScrollbarActivity);
1.3445 + scrollbarActivity->ActivityOccurred();
1.3446 + }
1.3447 +
1.3448 + bool isSmooth = aContent->HasAttr(kNameSpaceID_None, nsGkAtoms::smooth);
1.3449 + if (isSmooth) {
1.3450 + // Make sure an attribute-setting callback occurs even if the view
1.3451 + // didn't actually move yet. We need to make sure other listeners
1.3452 + // see that the scroll position is not (yet) what they thought it
1.3453 + // was.
1.3454 + nsWeakFrame weakFrame(mOuter);
1.3455 + UpdateScrollbarPosition();
1.3456 + if (!weakFrame.IsAlive()) {
1.3457 + return;
1.3458 + }
1.3459 + }
1.3460 + ScrollToWithOrigin(dest,
1.3461 + isSmooth ? nsIScrollableFrame::SMOOTH : nsIScrollableFrame::INSTANT,
1.3462 + nsGkAtoms::scrollbars, &allowedRange);
1.3463 + // 'this' might be destroyed here
1.3464 +}
1.3465 +
1.3466 +/* ============= Scroll events ========== */
1.3467 +
1.3468 +NS_IMETHODIMP
1.3469 +ScrollFrameHelper::ScrollEvent::Run()
1.3470 +{
1.3471 + if (mHelper)
1.3472 + mHelper->FireScrollEvent();
1.3473 + return NS_OK;
1.3474 +}
1.3475 +
1.3476 +void
1.3477 +ScrollFrameHelper::FireScrollEvent()
1.3478 +{
1.3479 + mScrollEvent.Forget();
1.3480 +
1.3481 + WidgetGUIEvent event(true, NS_SCROLL_EVENT, nullptr);
1.3482 + nsEventStatus status = nsEventStatus_eIgnore;
1.3483 + nsIContent* content = mOuter->GetContent();
1.3484 + nsPresContext* prescontext = mOuter->PresContext();
1.3485 + // Fire viewport scroll events at the document (where they
1.3486 + // will bubble to the window)
1.3487 + if (mIsRoot) {
1.3488 + nsIDocument* doc = content->GetCurrentDoc();
1.3489 + if (doc) {
1.3490 + EventDispatcher::Dispatch(doc, prescontext, &event, nullptr, &status);
1.3491 + }
1.3492 + } else {
1.3493 + // scroll events fired at elements don't bubble (although scroll events
1.3494 + // fired at documents do, to the window)
1.3495 + event.mFlags.mBubbles = false;
1.3496 + EventDispatcher::Dispatch(content, prescontext, &event, nullptr, &status);
1.3497 + }
1.3498 +}
1.3499 +
1.3500 +void
1.3501 +ScrollFrameHelper::PostScrollEvent()
1.3502 +{
1.3503 + if (mScrollEvent.IsPending())
1.3504 + return;
1.3505 +
1.3506 + nsRootPresContext* rpc = mOuter->PresContext()->GetRootPresContext();
1.3507 + if (!rpc)
1.3508 + return;
1.3509 + mScrollEvent = new ScrollEvent(this);
1.3510 + rpc->AddWillPaintObserver(mScrollEvent.get());
1.3511 +}
1.3512 +
1.3513 +NS_IMETHODIMP
1.3514 +ScrollFrameHelper::AsyncScrollPortEvent::Run()
1.3515 +{
1.3516 + if (mHelper) {
1.3517 + mHelper->mOuter->PresContext()->GetPresShell()->
1.3518 + FlushPendingNotifications(Flush_InterruptibleLayout);
1.3519 + }
1.3520 + return mHelper ? mHelper->FireScrollPortEvent() : NS_OK;
1.3521 +}
1.3522 +
1.3523 +bool
1.3524 +nsXULScrollFrame::AddHorizontalScrollbar(nsBoxLayoutState& aState, bool aOnBottom)
1.3525 +{
1.3526 + if (!mHelper.mHScrollbarBox)
1.3527 + return true;
1.3528 +
1.3529 + return AddRemoveScrollbar(aState, aOnBottom, true, true);
1.3530 +}
1.3531 +
1.3532 +bool
1.3533 +nsXULScrollFrame::AddVerticalScrollbar(nsBoxLayoutState& aState, bool aOnRight)
1.3534 +{
1.3535 + if (!mHelper.mVScrollbarBox)
1.3536 + return true;
1.3537 +
1.3538 + return AddRemoveScrollbar(aState, aOnRight, false, true);
1.3539 +}
1.3540 +
1.3541 +void
1.3542 +nsXULScrollFrame::RemoveHorizontalScrollbar(nsBoxLayoutState& aState, bool aOnBottom)
1.3543 +{
1.3544 + // removing a scrollbar should always fit
1.3545 + DebugOnly<bool> result = AddRemoveScrollbar(aState, aOnBottom, true, false);
1.3546 + NS_ASSERTION(result, "Removing horizontal scrollbar failed to fit??");
1.3547 +}
1.3548 +
1.3549 +void
1.3550 +nsXULScrollFrame::RemoveVerticalScrollbar(nsBoxLayoutState& aState, bool aOnRight)
1.3551 +{
1.3552 + // removing a scrollbar should always fit
1.3553 + DebugOnly<bool> result = AddRemoveScrollbar(aState, aOnRight, false, false);
1.3554 + NS_ASSERTION(result, "Removing vertical scrollbar failed to fit??");
1.3555 +}
1.3556 +
1.3557 +bool
1.3558 +nsXULScrollFrame::AddRemoveScrollbar(nsBoxLayoutState& aState,
1.3559 + bool aOnRightOrBottom, bool aHorizontal, bool aAdd)
1.3560 +{
1.3561 + if (aHorizontal) {
1.3562 + if (mHelper.mNeverHasHorizontalScrollbar || !mHelper.mHScrollbarBox)
1.3563 + return false;
1.3564 +
1.3565 + nsSize hSize = mHelper.mHScrollbarBox->GetPrefSize(aState);
1.3566 + nsBox::AddMargin(mHelper.mHScrollbarBox, hSize);
1.3567 +
1.3568 + mHelper.SetScrollbarVisibility(mHelper.mHScrollbarBox, aAdd);
1.3569 +
1.3570 + bool hasHorizontalScrollbar;
1.3571 + bool fit = AddRemoveScrollbar(hasHorizontalScrollbar,
1.3572 + mHelper.mScrollPort.y,
1.3573 + mHelper.mScrollPort.height,
1.3574 + hSize.height, aOnRightOrBottom, aAdd);
1.3575 + mHelper.mHasHorizontalScrollbar = hasHorizontalScrollbar; // because mHasHorizontalScrollbar is a bool
1.3576 + if (!fit)
1.3577 + mHelper.SetScrollbarVisibility(mHelper.mHScrollbarBox, !aAdd);
1.3578 +
1.3579 + return fit;
1.3580 + } else {
1.3581 + if (mHelper.mNeverHasVerticalScrollbar || !mHelper.mVScrollbarBox)
1.3582 + return false;
1.3583 +
1.3584 + nsSize vSize = mHelper.mVScrollbarBox->GetPrefSize(aState);
1.3585 + nsBox::AddMargin(mHelper.mVScrollbarBox, vSize);
1.3586 +
1.3587 + mHelper.SetScrollbarVisibility(mHelper.mVScrollbarBox, aAdd);
1.3588 +
1.3589 + bool hasVerticalScrollbar;
1.3590 + bool fit = AddRemoveScrollbar(hasVerticalScrollbar,
1.3591 + mHelper.mScrollPort.x,
1.3592 + mHelper.mScrollPort.width,
1.3593 + vSize.width, aOnRightOrBottom, aAdd);
1.3594 + mHelper.mHasVerticalScrollbar = hasVerticalScrollbar; // because mHasVerticalScrollbar is a bool
1.3595 + if (!fit)
1.3596 + mHelper.SetScrollbarVisibility(mHelper.mVScrollbarBox, !aAdd);
1.3597 +
1.3598 + return fit;
1.3599 + }
1.3600 +}
1.3601 +
1.3602 +bool
1.3603 +nsXULScrollFrame::AddRemoveScrollbar(bool& aHasScrollbar, nscoord& aXY,
1.3604 + nscoord& aSize, nscoord aSbSize,
1.3605 + bool aOnRightOrBottom, bool aAdd)
1.3606 +{
1.3607 + nscoord size = aSize;
1.3608 + nscoord xy = aXY;
1.3609 +
1.3610 + if (size != NS_INTRINSICSIZE) {
1.3611 + if (aAdd) {
1.3612 + size -= aSbSize;
1.3613 + if (!aOnRightOrBottom && size >= 0)
1.3614 + xy += aSbSize;
1.3615 + } else {
1.3616 + size += aSbSize;
1.3617 + if (!aOnRightOrBottom)
1.3618 + xy -= aSbSize;
1.3619 + }
1.3620 + }
1.3621 +
1.3622 + // not enough room? Yes? Return true.
1.3623 + if (size >= 0) {
1.3624 + aHasScrollbar = aAdd;
1.3625 + aSize = size;
1.3626 + aXY = xy;
1.3627 + return true;
1.3628 + }
1.3629 +
1.3630 + aHasScrollbar = false;
1.3631 + return false;
1.3632 +}
1.3633 +
1.3634 +void
1.3635 +nsXULScrollFrame::LayoutScrollArea(nsBoxLayoutState& aState,
1.3636 + const nsPoint& aScrollPosition)
1.3637 +{
1.3638 + uint32_t oldflags = aState.LayoutFlags();
1.3639 + nsRect childRect = nsRect(mHelper.mScrollPort.TopLeft() - aScrollPosition,
1.3640 + mHelper.mScrollPort.Size());
1.3641 + int32_t flags = NS_FRAME_NO_MOVE_VIEW;
1.3642 +
1.3643 + nsSize minSize = mHelper.mScrolledFrame->GetMinSize(aState);
1.3644 +
1.3645 + if (minSize.height > childRect.height)
1.3646 + childRect.height = minSize.height;
1.3647 +
1.3648 + if (minSize.width > childRect.width)
1.3649 + childRect.width = minSize.width;
1.3650 +
1.3651 + aState.SetLayoutFlags(flags);
1.3652 + ClampAndSetBounds(aState, childRect, aScrollPosition);
1.3653 + mHelper.mScrolledFrame->Layout(aState);
1.3654 +
1.3655 + childRect = mHelper.mScrolledFrame->GetRect();
1.3656 +
1.3657 + if (childRect.width < mHelper.mScrollPort.width ||
1.3658 + childRect.height < mHelper.mScrollPort.height)
1.3659 + {
1.3660 + childRect.width = std::max(childRect.width, mHelper.mScrollPort.width);
1.3661 + childRect.height = std::max(childRect.height, mHelper.mScrollPort.height);
1.3662 +
1.3663 + // remove overflow areas when we update the bounds,
1.3664 + // because we've already accounted for it
1.3665 + // REVIEW: Have we accounted for both?
1.3666 + ClampAndSetBounds(aState, childRect, aScrollPosition, true);
1.3667 + }
1.3668 +
1.3669 + aState.SetLayoutFlags(oldflags);
1.3670 +
1.3671 +}
1.3672 +
1.3673 +void ScrollFrameHelper::PostOverflowEvent()
1.3674 +{
1.3675 + if (mAsyncScrollPortEvent.IsPending())
1.3676 + return;
1.3677 +
1.3678 + // Keep this in sync with FireScrollPortEvent().
1.3679 + nsSize scrollportSize = mScrollPort.Size();
1.3680 + nsSize childSize = GetScrolledRect().Size();
1.3681 +
1.3682 + bool newVerticalOverflow = childSize.height > scrollportSize.height;
1.3683 + bool vertChanged = mVerticalOverflow != newVerticalOverflow;
1.3684 +
1.3685 + bool newHorizontalOverflow = childSize.width > scrollportSize.width;
1.3686 + bool horizChanged = mHorizontalOverflow != newHorizontalOverflow;
1.3687 +
1.3688 + if (!vertChanged && !horizChanged) {
1.3689 + return;
1.3690 + }
1.3691 +
1.3692 + nsRootPresContext* rpc = mOuter->PresContext()->GetRootPresContext();
1.3693 + if (!rpc)
1.3694 + return;
1.3695 +
1.3696 + mAsyncScrollPortEvent = new AsyncScrollPortEvent(this);
1.3697 + rpc->AddWillPaintObserver(mAsyncScrollPortEvent.get());
1.3698 +}
1.3699 +
1.3700 +bool
1.3701 +ScrollFrameHelper::IsLTR() const
1.3702 +{
1.3703 + //TODO make bidi code set these from preferences
1.3704 +
1.3705 + nsIFrame *frame = mOuter;
1.3706 + // XXX This is a bit on the slow side.
1.3707 + if (mIsRoot) {
1.3708 + // If we're the root scrollframe, we need the root element's style data.
1.3709 + nsPresContext *presContext = mOuter->PresContext();
1.3710 + nsIDocument *document = presContext->Document();
1.3711 + Element *root = document->GetRootElement();
1.3712 +
1.3713 + // But for HTML and XHTML we want the body element.
1.3714 + nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(document);
1.3715 + if (htmlDoc) {
1.3716 + Element *bodyElement = document->GetBodyElement();
1.3717 + if (bodyElement)
1.3718 + root = bodyElement; // we can trust the document to hold on to it
1.3719 + }
1.3720 +
1.3721 + if (root) {
1.3722 + nsIFrame *rootsFrame = root->GetPrimaryFrame();
1.3723 + if (rootsFrame)
1.3724 + frame = rootsFrame;
1.3725 + }
1.3726 + }
1.3727 +
1.3728 + return frame->StyleVisibility()->mDirection != NS_STYLE_DIRECTION_RTL;
1.3729 +}
1.3730 +
1.3731 +bool
1.3732 +ScrollFrameHelper::IsScrollbarOnRight() const
1.3733 +{
1.3734 + nsPresContext *presContext = mOuter->PresContext();
1.3735 +
1.3736 + // The position of the scrollbar in top-level windows depends on the pref
1.3737 + // layout.scrollbar.side. For non-top-level elements, it depends only on the
1.3738 + // directionaliy of the element (equivalent to a value of "1" for the pref).
1.3739 + if (!mIsRoot)
1.3740 + return IsLTR();
1.3741 + switch (presContext->GetCachedIntPref(kPresContext_ScrollbarSide)) {
1.3742 + default:
1.3743 + case 0: // UI directionality
1.3744 + return presContext->GetCachedIntPref(kPresContext_BidiDirection)
1.3745 + == IBMBIDI_TEXTDIRECTION_LTR;
1.3746 + case 1: // Document / content directionality
1.3747 + return IsLTR();
1.3748 + case 2: // Always right
1.3749 + return true;
1.3750 + case 3: // Always left
1.3751 + return false;
1.3752 + }
1.3753 +}
1.3754 +
1.3755 +/**
1.3756 + * Reflow the scroll area if it needs it and return its size. Also determine if the reflow will
1.3757 + * cause any of the scrollbars to need to be reflowed.
1.3758 + */
1.3759 +nsresult
1.3760 +nsXULScrollFrame::Layout(nsBoxLayoutState& aState)
1.3761 +{
1.3762 + bool scrollbarRight = mHelper.IsScrollbarOnRight();
1.3763 + bool scrollbarBottom = true;
1.3764 +
1.3765 + // get the content rect
1.3766 + nsRect clientRect(0,0,0,0);
1.3767 + GetClientRect(clientRect);
1.3768 +
1.3769 + nsRect oldScrollAreaBounds = mHelper.mScrollPort;
1.3770 + nsPoint oldScrollPosition = mHelper.GetLogicalScrollPosition();
1.3771 +
1.3772 + // the scroll area size starts off as big as our content area
1.3773 + mHelper.mScrollPort = clientRect;
1.3774 +
1.3775 + /**************
1.3776 + Our basic strategy here is to first try laying out the content with
1.3777 + the scrollbars in their current state. We're hoping that that will
1.3778 + just "work"; the content will overflow wherever there's a scrollbar
1.3779 + already visible. If that does work, then there's no need to lay out
1.3780 + the scrollarea. Otherwise we fix up the scrollbars; first we add a
1.3781 + vertical one to scroll the content if necessary, or remove it if
1.3782 + it's not needed. Then we reflow the content if the scrollbar
1.3783 + changed. Then we add a horizontal scrollbar if necessary (or
1.3784 + remove if not needed), and if that changed, we reflow the content
1.3785 + again. At this point, any scrollbars that are needed to scroll the
1.3786 + content have been added.
1.3787 +
1.3788 + In the second phase we check to see if any scrollbars are too small
1.3789 + to display, and if so, we remove them. We check the horizontal
1.3790 + scrollbar first; removing it might make room for the vertical
1.3791 + scrollbar, and if we have room for just one scrollbar we'll save
1.3792 + the vertical one.
1.3793 +
1.3794 + Finally we position and size the scrollbars and scrollcorner (the
1.3795 + square that is needed in the corner of the window when two
1.3796 + scrollbars are visible), and reflow any fixed position views
1.3797 + (if we're the viewport and we added or removed a scrollbar).
1.3798 + **************/
1.3799 +
1.3800 + ScrollbarStyles styles = GetScrollbarStyles();
1.3801 +
1.3802 + // Look at our style do we always have vertical or horizontal scrollbars?
1.3803 + if (styles.mHorizontal == NS_STYLE_OVERFLOW_SCROLL)
1.3804 + mHelper.mHasHorizontalScrollbar = true;
1.3805 + if (styles.mVertical == NS_STYLE_OVERFLOW_SCROLL)
1.3806 + mHelper.mHasVerticalScrollbar = true;
1.3807 +
1.3808 + if (mHelper.mHasHorizontalScrollbar)
1.3809 + AddHorizontalScrollbar(aState, scrollbarBottom);
1.3810 +
1.3811 + if (mHelper.mHasVerticalScrollbar)
1.3812 + AddVerticalScrollbar(aState, scrollbarRight);
1.3813 +
1.3814 + // layout our the scroll area
1.3815 + LayoutScrollArea(aState, oldScrollPosition);
1.3816 +
1.3817 + // now look at the content area and see if we need scrollbars or not
1.3818 + bool needsLayout = false;
1.3819 +
1.3820 + // if we have 'auto' scrollbars look at the vertical case
1.3821 + if (styles.mVertical != NS_STYLE_OVERFLOW_SCROLL) {
1.3822 + // These are only good until the call to LayoutScrollArea.
1.3823 + nsRect scrolledRect = mHelper.GetScrolledRect();
1.3824 +
1.3825 + // There are two cases to consider
1.3826 + if (scrolledRect.height <= mHelper.mScrollPort.height
1.3827 + || styles.mVertical != NS_STYLE_OVERFLOW_AUTO) {
1.3828 + if (mHelper.mHasVerticalScrollbar) {
1.3829 + // We left room for the vertical scrollbar, but it's not needed;
1.3830 + // remove it.
1.3831 + RemoveVerticalScrollbar(aState, scrollbarRight);
1.3832 + needsLayout = true;
1.3833 + }
1.3834 + } else {
1.3835 + if (!mHelper.mHasVerticalScrollbar) {
1.3836 + // We didn't leave room for the vertical scrollbar, but it turns
1.3837 + // out we needed it
1.3838 + if (AddVerticalScrollbar(aState, scrollbarRight))
1.3839 + needsLayout = true;
1.3840 + }
1.3841 + }
1.3842 +
1.3843 + // ok layout at the right size
1.3844 + if (needsLayout) {
1.3845 + nsBoxLayoutState resizeState(aState);
1.3846 + LayoutScrollArea(resizeState, oldScrollPosition);
1.3847 + needsLayout = false;
1.3848 + }
1.3849 + }
1.3850 +
1.3851 +
1.3852 + // if scrollbars are auto look at the horizontal case
1.3853 + if (styles.mHorizontal != NS_STYLE_OVERFLOW_SCROLL)
1.3854 + {
1.3855 + // These are only good until the call to LayoutScrollArea.
1.3856 + nsRect scrolledRect = mHelper.GetScrolledRect();
1.3857 +
1.3858 + // if the child is wider that the scroll area
1.3859 + // and we don't have a scrollbar add one.
1.3860 + if ((scrolledRect.width > mHelper.mScrollPort.width)
1.3861 + && styles.mHorizontal == NS_STYLE_OVERFLOW_AUTO) {
1.3862 +
1.3863 + if (!mHelper.mHasHorizontalScrollbar) {
1.3864 + // no scrollbar?
1.3865 + if (AddHorizontalScrollbar(aState, scrollbarBottom))
1.3866 + needsLayout = true;
1.3867 +
1.3868 + // if we added a horizontal scrollbar and we did not have a vertical
1.3869 + // there is a chance that by adding the horizontal scrollbar we will
1.3870 + // suddenly need a vertical scrollbar. Is a special case but its
1.3871 + // important.
1.3872 + //if (!mHasVerticalScrollbar && scrolledRect.height > scrollAreaRect.height - sbSize.height)
1.3873 + // printf("****Gfx Scrollbar Special case hit!!*****\n");
1.3874 +
1.3875 + }
1.3876 + } else {
1.3877 + // if the area is smaller or equal to and we have a scrollbar then
1.3878 + // remove it.
1.3879 + if (mHelper.mHasHorizontalScrollbar) {
1.3880 + RemoveHorizontalScrollbar(aState, scrollbarBottom);
1.3881 + needsLayout = true;
1.3882 + }
1.3883 + }
1.3884 + }
1.3885 +
1.3886 + // we only need to set the rect. The inner child stays the same size.
1.3887 + if (needsLayout) {
1.3888 + nsBoxLayoutState resizeState(aState);
1.3889 + LayoutScrollArea(resizeState, oldScrollPosition);
1.3890 + needsLayout = false;
1.3891 + }
1.3892 +
1.3893 + // get the preferred size of the scrollbars
1.3894 + nsSize hMinSize(0, 0);
1.3895 + if (mHelper.mHScrollbarBox && mHelper.mHasHorizontalScrollbar) {
1.3896 + GetScrollbarMetrics(aState, mHelper.mHScrollbarBox, &hMinSize, nullptr, false);
1.3897 + }
1.3898 + nsSize vMinSize(0, 0);
1.3899 + if (mHelper.mVScrollbarBox && mHelper.mHasVerticalScrollbar) {
1.3900 + GetScrollbarMetrics(aState, mHelper.mVScrollbarBox, &vMinSize, nullptr, true);
1.3901 + }
1.3902 +
1.3903 + // Disable scrollbars that are too small
1.3904 + // Disable horizontal scrollbar first. If we have to disable only one
1.3905 + // scrollbar, we'd rather keep the vertical scrollbar.
1.3906 + // Note that we always give horizontal scrollbars their preferred height,
1.3907 + // never their min-height. So check that there's room for the preferred height.
1.3908 + if (mHelper.mHasHorizontalScrollbar &&
1.3909 + (hMinSize.width > clientRect.width - vMinSize.width
1.3910 + || hMinSize.height > clientRect.height)) {
1.3911 + RemoveHorizontalScrollbar(aState, scrollbarBottom);
1.3912 + needsLayout = true;
1.3913 + }
1.3914 + // Now disable vertical scrollbar if necessary
1.3915 + if (mHelper.mHasVerticalScrollbar &&
1.3916 + (vMinSize.height > clientRect.height - hMinSize.height
1.3917 + || vMinSize.width > clientRect.width)) {
1.3918 + RemoveVerticalScrollbar(aState, scrollbarRight);
1.3919 + needsLayout = true;
1.3920 + }
1.3921 +
1.3922 + // we only need to set the rect. The inner child stays the same size.
1.3923 + if (needsLayout) {
1.3924 + nsBoxLayoutState resizeState(aState);
1.3925 + LayoutScrollArea(resizeState, oldScrollPosition);
1.3926 + }
1.3927 +
1.3928 + if (!mHelper.mSupppressScrollbarUpdate) {
1.3929 + mHelper.LayoutScrollbars(aState, clientRect, oldScrollAreaBounds);
1.3930 + }
1.3931 + if (!mHelper.mPostedReflowCallback) {
1.3932 + // Make sure we'll try scrolling to restored position
1.3933 + PresContext()->PresShell()->PostReflowCallback(&mHelper);
1.3934 + mHelper.mPostedReflowCallback = true;
1.3935 + }
1.3936 + if (!(GetStateBits() & NS_FRAME_FIRST_REFLOW)) {
1.3937 + mHelper.mHadNonInitialReflow = true;
1.3938 + }
1.3939 +
1.3940 + mHelper.UpdateSticky();
1.3941 +
1.3942 + // Set up overflow areas for block frames for the benefit of
1.3943 + // text-overflow.
1.3944 + nsIFrame* f = mHelper.mScrolledFrame->GetContentInsertionFrame();
1.3945 + if (nsLayoutUtils::GetAsBlock(f)) {
1.3946 + nsRect origRect = f->GetRect();
1.3947 + nsRect clippedRect = origRect;
1.3948 + clippedRect.MoveBy(mHelper.mScrollPort.TopLeft());
1.3949 + clippedRect.IntersectRect(clippedRect, mHelper.mScrollPort);
1.3950 + nsOverflowAreas overflow = f->GetOverflowAreas();
1.3951 + f->FinishAndStoreOverflow(overflow, clippedRect.Size());
1.3952 + clippedRect.MoveTo(origRect.TopLeft());
1.3953 + f->SetRect(clippedRect);
1.3954 + }
1.3955 +
1.3956 + mHelper.PostOverflowEvent();
1.3957 + return NS_OK;
1.3958 +}
1.3959 +
1.3960 +void
1.3961 +ScrollFrameHelper::FinishReflowForScrollbar(nsIContent* aContent,
1.3962 + nscoord aMinXY, nscoord aMaxXY,
1.3963 + nscoord aCurPosXY,
1.3964 + nscoord aPageIncrement,
1.3965 + nscoord aIncrement)
1.3966 +{
1.3967 + // Scrollbars assume zero is the minimum position, so translate for them.
1.3968 + SetCoordAttribute(aContent, nsGkAtoms::curpos, aCurPosXY - aMinXY);
1.3969 + SetScrollbarEnabled(aContent, aMaxXY - aMinXY);
1.3970 + SetCoordAttribute(aContent, nsGkAtoms::maxpos, aMaxXY - aMinXY);
1.3971 + SetCoordAttribute(aContent, nsGkAtoms::pageincrement, aPageIncrement);
1.3972 + SetCoordAttribute(aContent, nsGkAtoms::increment, aIncrement);
1.3973 +}
1.3974 +
1.3975 +bool
1.3976 +ScrollFrameHelper::ReflowFinished()
1.3977 +{
1.3978 + nsAutoScriptBlocker scriptBlocker;
1.3979 + mPostedReflowCallback = false;
1.3980 +
1.3981 + ScrollToRestoredPosition();
1.3982 +
1.3983 + // Clamp current scroll position to new bounds. Normally this won't
1.3984 + // do anything.
1.3985 + nsPoint currentScrollPos = GetScrollPosition();
1.3986 + ScrollToImpl(currentScrollPos, nsRect(currentScrollPos, nsSize(0, 0)));
1.3987 + if (!mAsyncScroll) {
1.3988 + // We need to have mDestination track the current scroll position,
1.3989 + // in case it falls outside the new reflow area. mDestination is used
1.3990 + // by ScrollBy as its starting position.
1.3991 + mDestination = GetScrollPosition();
1.3992 + }
1.3993 +
1.3994 + if (NS_SUBTREE_DIRTY(mOuter) || !mUpdateScrollbarAttributes)
1.3995 + return false;
1.3996 +
1.3997 + mUpdateScrollbarAttributes = false;
1.3998 +
1.3999 + // Update scrollbar attributes.
1.4000 + nsPresContext* presContext = mOuter->PresContext();
1.4001 +
1.4002 + if (mMayHaveDirtyFixedChildren) {
1.4003 + mMayHaveDirtyFixedChildren = false;
1.4004 + nsIFrame* parentFrame = mOuter->GetParent();
1.4005 + for (nsIFrame* fixedChild =
1.4006 + parentFrame->GetFirstChild(nsIFrame::kFixedList);
1.4007 + fixedChild; fixedChild = fixedChild->GetNextSibling()) {
1.4008 + // force a reflow of the fixed child
1.4009 + presContext->PresShell()->
1.4010 + FrameNeedsReflow(fixedChild, nsIPresShell::eResize,
1.4011 + NS_FRAME_HAS_DIRTY_CHILDREN);
1.4012 + }
1.4013 + }
1.4014 +
1.4015 + nsRect scrolledContentRect = GetScrolledRect();
1.4016 + nscoord minX = scrolledContentRect.x;
1.4017 + nscoord maxX = scrolledContentRect.XMost() - mScrollPort.width;
1.4018 + nscoord minY = scrolledContentRect.y;
1.4019 + nscoord maxY = scrolledContentRect.YMost() - mScrollPort.height;
1.4020 +
1.4021 + // Suppress handling of the curpos attribute changes we make here.
1.4022 + NS_ASSERTION(!mFrameIsUpdatingScrollbar, "We shouldn't be reentering here");
1.4023 + mFrameIsUpdatingScrollbar = true;
1.4024 +
1.4025 + nsCOMPtr<nsIContent> vScroll =
1.4026 + mVScrollbarBox ? mVScrollbarBox->GetContent() : nullptr;
1.4027 + nsCOMPtr<nsIContent> hScroll =
1.4028 + mHScrollbarBox ? mHScrollbarBox->GetContent() : nullptr;
1.4029 +
1.4030 + // Note, in some cases mOuter may get deleted while finishing reflow
1.4031 + // for scrollbars. XXXmats is this still true now that we have a script
1.4032 + // blocker in this scope? (if not, remove the weak frame checks below).
1.4033 + if (vScroll || hScroll) {
1.4034 + nsWeakFrame weakFrame(mOuter);
1.4035 + nsPoint scrollPos = GetScrollPosition();
1.4036 + nsSize lineScrollAmount = GetLineScrollAmount();
1.4037 + if (vScroll) {
1.4038 + const double kScrollMultiplier =
1.4039 + Preferences::GetInt("toolkit.scrollbox.verticalScrollDistance",
1.4040 + NS_DEFAULT_VERTICAL_SCROLL_DISTANCE);
1.4041 + nscoord increment = lineScrollAmount.height * kScrollMultiplier;
1.4042 + // We normally use (scrollArea.height - increment) for height
1.4043 + // of page scrolling. However, it is too small when
1.4044 + // increment is very large. (If increment is larger than
1.4045 + // scrollArea.height, direction of scrolling will be opposite).
1.4046 + // To avoid it, we use (float(scrollArea.height) * 0.8) as
1.4047 + // lower bound value of height of page scrolling. (bug 383267)
1.4048 + // XXX shouldn't we use GetPageScrollAmount here?
1.4049 + nscoord pageincrement = nscoord(mScrollPort.height - increment);
1.4050 + nscoord pageincrementMin = nscoord(float(mScrollPort.height) * 0.8);
1.4051 + FinishReflowForScrollbar(vScroll, minY, maxY, scrollPos.y,
1.4052 + std::max(pageincrement, pageincrementMin),
1.4053 + increment);
1.4054 + }
1.4055 + if (hScroll) {
1.4056 + const double kScrollMultiplier =
1.4057 + Preferences::GetInt("toolkit.scrollbox.horizontalScrollDistance",
1.4058 + NS_DEFAULT_HORIZONTAL_SCROLL_DISTANCE);
1.4059 + nscoord increment = lineScrollAmount.width * kScrollMultiplier;
1.4060 + FinishReflowForScrollbar(hScroll, minX, maxX, scrollPos.x,
1.4061 + nscoord(float(mScrollPort.width) * 0.8),
1.4062 + increment);
1.4063 + }
1.4064 + NS_ENSURE_TRUE(weakFrame.IsAlive(), false);
1.4065 + }
1.4066 +
1.4067 + mFrameIsUpdatingScrollbar = false;
1.4068 + // We used to rely on the curpos attribute changes above to scroll the
1.4069 + // view. However, for scrolling to the left of the viewport, we
1.4070 + // rescale the curpos attribute, which means that operations like
1.4071 + // resizing the window while it is scrolled all the way to the left
1.4072 + // hold the curpos attribute constant at 0 while still requiring
1.4073 + // scrolling. So we suppress the effect of the changes above with
1.4074 + // mFrameIsUpdatingScrollbar and call CurPosAttributeChanged here.
1.4075 + // (It actually even works some of the time without this, thanks to
1.4076 + // nsSliderFrame::AttributeChanged's handling of maxpos, but not when
1.4077 + // we hide the scrollbar on a large size change, such as
1.4078 + // maximization.)
1.4079 + if (!mHScrollbarBox && !mVScrollbarBox)
1.4080 + return false;
1.4081 + CurPosAttributeChanged(mVScrollbarBox ? mVScrollbarBox->GetContent()
1.4082 + : mHScrollbarBox->GetContent());
1.4083 + return true;
1.4084 +}
1.4085 +
1.4086 +void
1.4087 +ScrollFrameHelper::ReflowCallbackCanceled()
1.4088 +{
1.4089 + mPostedReflowCallback = false;
1.4090 +}
1.4091 +
1.4092 +bool
1.4093 +ScrollFrameHelper::UpdateOverflow()
1.4094 +{
1.4095 + nsIScrollableFrame* sf = do_QueryFrame(mOuter);
1.4096 + ScrollbarStyles ss = sf->GetScrollbarStyles();
1.4097 +
1.4098 + if (ss.mVertical != NS_STYLE_OVERFLOW_HIDDEN ||
1.4099 + ss.mHorizontal != NS_STYLE_OVERFLOW_HIDDEN ||
1.4100 + GetScrollPosition() != nsPoint()) {
1.4101 + // If there are scrollbars, or we're not at the beginning of the pane,
1.4102 + // the scroll position may change. In this case, mark the frame as
1.4103 + // needing reflow. Don't use NS_FRAME_IS_DIRTY as dirty as that means
1.4104 + // we have to reflow the frame and all its descendants, and we don't
1.4105 + // have to do that here. Only this frame needs to be reflowed.
1.4106 + mOuter->PresContext()->PresShell()->FrameNeedsReflow(
1.4107 + mOuter, nsIPresShell::eResize, NS_FRAME_HAS_DIRTY_CHILDREN);
1.4108 + // Ensure that next time nsHTMLScrollFrame::Reflow runs, we don't skip
1.4109 + // updating the scrollbars. (Because the overflow area of the scrolled
1.4110 + // frame has probably just been updated, Reflow won't see it change.)
1.4111 + mSkippedScrollbarLayout = true;
1.4112 + return false; // reflowing will update overflow
1.4113 + }
1.4114 + PostOverflowEvent();
1.4115 + return mOuter->nsContainerFrame::UpdateOverflow();
1.4116 +}
1.4117 +
1.4118 +void
1.4119 +ScrollFrameHelper::UpdateSticky()
1.4120 +{
1.4121 + StickyScrollContainer* ssc = StickyScrollContainer::
1.4122 + GetStickyScrollContainerForScrollFrame(mOuter);
1.4123 + if (ssc) {
1.4124 + nsIScrollableFrame* scrollFrame = do_QueryFrame(mOuter);
1.4125 + ssc->UpdatePositions(scrollFrame->GetScrollPosition(), mOuter);
1.4126 + }
1.4127 +}
1.4128 +
1.4129 +void
1.4130 +ScrollFrameHelper::AdjustScrollbarRectForResizer(
1.4131 + nsIFrame* aFrame, nsPresContext* aPresContext,
1.4132 + nsRect& aRect, bool aHasResizer, bool aVertical)
1.4133 +{
1.4134 + if ((aVertical ? aRect.width : aRect.height) == 0)
1.4135 + return;
1.4136 +
1.4137 + // if a content resizer is present, use its size. Otherwise, check if the
1.4138 + // widget has a resizer.
1.4139 + nsRect resizerRect;
1.4140 + if (aHasResizer) {
1.4141 + resizerRect = mResizerBox->GetRect();
1.4142 + }
1.4143 + else {
1.4144 + nsPoint offset;
1.4145 + nsIWidget* widget = aFrame->GetNearestWidget(offset);
1.4146 + nsIntRect widgetRect;
1.4147 + if (!widget || !widget->ShowsResizeIndicator(&widgetRect))
1.4148 + return;
1.4149 +
1.4150 + resizerRect = nsRect(aPresContext->DevPixelsToAppUnits(widgetRect.x) - offset.x,
1.4151 + aPresContext->DevPixelsToAppUnits(widgetRect.y) - offset.y,
1.4152 + aPresContext->DevPixelsToAppUnits(widgetRect.width),
1.4153 + aPresContext->DevPixelsToAppUnits(widgetRect.height));
1.4154 + }
1.4155 +
1.4156 + if (!resizerRect.Contains(aRect.BottomRight() - nsPoint(1, 1)))
1.4157 + return;
1.4158 +
1.4159 + if (aVertical)
1.4160 + aRect.height = std::max(0, resizerRect.y - aRect.y);
1.4161 + else
1.4162 + aRect.width = std::max(0, resizerRect.x - aRect.x);
1.4163 +}
1.4164 +
1.4165 +static void
1.4166 +AdjustOverlappingScrollbars(nsRect& aVRect, nsRect& aHRect)
1.4167 +{
1.4168 + if (aVRect.IsEmpty() || aHRect.IsEmpty())
1.4169 + return;
1.4170 +
1.4171 + const nsRect oldVRect = aVRect;
1.4172 + const nsRect oldHRect = aHRect;
1.4173 + if (oldVRect.Contains(oldHRect.BottomRight() - nsPoint(1, 1))) {
1.4174 + aHRect.width = std::max(0, oldVRect.x - oldHRect.x);
1.4175 + } else if (oldVRect.Contains(oldHRect.BottomLeft() - nsPoint(0, 1))) {
1.4176 + nscoord overlap = std::min(oldHRect.width, oldVRect.XMost() - oldHRect.x);
1.4177 + aHRect.x += overlap;
1.4178 + aHRect.width -= overlap;
1.4179 + }
1.4180 + if (oldHRect.Contains(oldVRect.BottomRight() - nsPoint(1, 1))) {
1.4181 + aVRect.height = std::max(0, oldHRect.y - oldVRect.y);
1.4182 + }
1.4183 +}
1.4184 +
1.4185 +void
1.4186 +ScrollFrameHelper::LayoutScrollbars(nsBoxLayoutState& aState,
1.4187 + const nsRect& aContentArea,
1.4188 + const nsRect& aOldScrollArea)
1.4189 +{
1.4190 + NS_ASSERTION(!mSupppressScrollbarUpdate,
1.4191 + "This should have been suppressed");
1.4192 +
1.4193 + bool hasResizer = HasResizer();
1.4194 + bool scrollbarOnLeft = !IsScrollbarOnRight();
1.4195 +
1.4196 + // place the scrollcorner
1.4197 + if (mScrollCornerBox || mResizerBox) {
1.4198 + NS_PRECONDITION(!mScrollCornerBox || mScrollCornerBox->IsBoxFrame(), "Must be a box frame!");
1.4199 +
1.4200 + nsRect r(0, 0, 0, 0);
1.4201 + if (aContentArea.x != mScrollPort.x || scrollbarOnLeft) {
1.4202 + // scrollbar (if any) on left
1.4203 + r.x = aContentArea.x;
1.4204 + r.width = mScrollPort.x - aContentArea.x;
1.4205 + NS_ASSERTION(r.width >= 0, "Scroll area should be inside client rect");
1.4206 + } else {
1.4207 + // scrollbar (if any) on right
1.4208 + r.width = aContentArea.XMost() - mScrollPort.XMost();
1.4209 + r.x = aContentArea.XMost() - r.width;
1.4210 + NS_ASSERTION(r.width >= 0, "Scroll area should be inside client rect");
1.4211 + }
1.4212 + if (aContentArea.y != mScrollPort.y) {
1.4213 + NS_ERROR("top scrollbars not supported");
1.4214 + } else {
1.4215 + // scrollbar (if any) on bottom
1.4216 + r.height = aContentArea.YMost() - mScrollPort.YMost();
1.4217 + r.y = aContentArea.YMost() - r.height;
1.4218 + NS_ASSERTION(r.height >= 0, "Scroll area should be inside client rect");
1.4219 + }
1.4220 +
1.4221 + if (mScrollCornerBox) {
1.4222 + nsBoxFrame::LayoutChildAt(aState, mScrollCornerBox, r);
1.4223 + }
1.4224 +
1.4225 + if (hasResizer) {
1.4226 + // if a resizer is present, get its size. Assume a default size of 15 pixels.
1.4227 + nscoord defaultSize = nsPresContext::CSSPixelsToAppUnits(15);
1.4228 + nsSize resizerMinSize = mResizerBox->GetMinSize(aState);
1.4229 +
1.4230 + nscoord vScrollbarWidth = mVScrollbarBox ?
1.4231 + mVScrollbarBox->GetPrefSize(aState).width : defaultSize;
1.4232 + r.width = std::max(std::max(r.width, vScrollbarWidth), resizerMinSize.width);
1.4233 + if (aContentArea.x == mScrollPort.x && !scrollbarOnLeft) {
1.4234 + r.x = aContentArea.XMost() - r.width;
1.4235 + }
1.4236 +
1.4237 + nscoord hScrollbarHeight = mHScrollbarBox ?
1.4238 + mHScrollbarBox->GetPrefSize(aState).height : defaultSize;
1.4239 + r.height = std::max(std::max(r.height, hScrollbarHeight), resizerMinSize.height);
1.4240 + if (aContentArea.y == mScrollPort.y) {
1.4241 + r.y = aContentArea.YMost() - r.height;
1.4242 + }
1.4243 +
1.4244 + nsBoxFrame::LayoutChildAt(aState, mResizerBox, r);
1.4245 + }
1.4246 + else if (mResizerBox) {
1.4247 + // otherwise lay out the resizer with an empty rectangle
1.4248 + nsBoxFrame::LayoutChildAt(aState, mResizerBox, nsRect());
1.4249 + }
1.4250 + }
1.4251 +
1.4252 + nsPresContext* presContext = mScrolledFrame->PresContext();
1.4253 + nsRect vRect;
1.4254 + if (mVScrollbarBox) {
1.4255 + NS_PRECONDITION(mVScrollbarBox->IsBoxFrame(), "Must be a box frame!");
1.4256 + vRect = mScrollPort;
1.4257 + vRect.width = aContentArea.width - mScrollPort.width;
1.4258 + vRect.x = scrollbarOnLeft ? aContentArea.x : mScrollPort.XMost();
1.4259 + if (mHasVerticalScrollbar) {
1.4260 + nsMargin margin;
1.4261 + mVScrollbarBox->GetMargin(margin);
1.4262 + vRect.Deflate(margin);
1.4263 + }
1.4264 + AdjustScrollbarRectForResizer(mOuter, presContext, vRect, hasResizer, true);
1.4265 + }
1.4266 +
1.4267 + nsRect hRect;
1.4268 + if (mHScrollbarBox) {
1.4269 + NS_PRECONDITION(mHScrollbarBox->IsBoxFrame(), "Must be a box frame!");
1.4270 + hRect = mScrollPort;
1.4271 + hRect.height = aContentArea.height - mScrollPort.height;
1.4272 + hRect.y = true ? mScrollPort.YMost() : aContentArea.y;
1.4273 + if (mHasHorizontalScrollbar) {
1.4274 + nsMargin margin;
1.4275 + mHScrollbarBox->GetMargin(margin);
1.4276 + hRect.Deflate(margin);
1.4277 + }
1.4278 + AdjustScrollbarRectForResizer(mOuter, presContext, hRect, hasResizer, false);
1.4279 + }
1.4280 +
1.4281 + if (!LookAndFeel::GetInt(LookAndFeel::eIntID_AllowOverlayScrollbarsOverlap)) {
1.4282 + AdjustOverlappingScrollbars(vRect, hRect);
1.4283 + }
1.4284 + if (mVScrollbarBox) {
1.4285 + nsBoxFrame::LayoutChildAt(aState, mVScrollbarBox, vRect);
1.4286 + }
1.4287 + if (mHScrollbarBox) {
1.4288 + nsBoxFrame::LayoutChildAt(aState, mHScrollbarBox, hRect);
1.4289 + }
1.4290 +
1.4291 + // may need to update fixed position children of the viewport,
1.4292 + // if the client area changed size because of an incremental
1.4293 + // reflow of a descendant. (If the outer frame is dirty, the fixed
1.4294 + // children will be re-laid out anyway)
1.4295 + if (aOldScrollArea.Size() != mScrollPort.Size() &&
1.4296 + !(mOuter->GetStateBits() & NS_FRAME_IS_DIRTY) &&
1.4297 + mIsRoot) {
1.4298 + mMayHaveDirtyFixedChildren = true;
1.4299 + }
1.4300 +
1.4301 + // post reflow callback to modify scrollbar attributes
1.4302 + mUpdateScrollbarAttributes = true;
1.4303 + if (!mPostedReflowCallback) {
1.4304 + aState.PresContext()->PresShell()->PostReflowCallback(this);
1.4305 + mPostedReflowCallback = true;
1.4306 + }
1.4307 +}
1.4308 +
1.4309 +#if DEBUG
1.4310 +static bool ShellIsAlive(nsWeakPtr& aWeakPtr)
1.4311 +{
1.4312 + nsCOMPtr<nsIPresShell> shell(do_QueryReferent(aWeakPtr));
1.4313 + return !!shell;
1.4314 +}
1.4315 +#endif
1.4316 +
1.4317 +void
1.4318 +ScrollFrameHelper::SetScrollbarEnabled(nsIContent* aContent, nscoord aMaxPos)
1.4319 +{
1.4320 + DebugOnly<nsWeakPtr> weakShell(
1.4321 + do_GetWeakReference(mOuter->PresContext()->PresShell()));
1.4322 + if (aMaxPos) {
1.4323 + aContent->UnsetAttr(kNameSpaceID_None, nsGkAtoms::disabled, true);
1.4324 + } else {
1.4325 + aContent->SetAttr(kNameSpaceID_None, nsGkAtoms::disabled,
1.4326 + NS_LITERAL_STRING("true"), true);
1.4327 + }
1.4328 + MOZ_ASSERT(ShellIsAlive(weakShell), "pres shell was destroyed by scrolling");
1.4329 +}
1.4330 +
1.4331 +void
1.4332 +ScrollFrameHelper::SetCoordAttribute(nsIContent* aContent, nsIAtom* aAtom,
1.4333 + nscoord aSize)
1.4334 +{
1.4335 + DebugOnly<nsWeakPtr> weakShell(
1.4336 + do_GetWeakReference(mOuter->PresContext()->PresShell()));
1.4337 + // convert to pixels
1.4338 + aSize = nsPresContext::AppUnitsToIntCSSPixels(aSize);
1.4339 +
1.4340 + // only set the attribute if it changed.
1.4341 +
1.4342 + nsAutoString newValue;
1.4343 + newValue.AppendInt(aSize);
1.4344 +
1.4345 + if (aContent->AttrValueIs(kNameSpaceID_None, aAtom, newValue, eCaseMatters))
1.4346 + return;
1.4347 +
1.4348 + nsWeakFrame weakFrame(mOuter);
1.4349 + nsCOMPtr<nsIContent> kungFuDeathGrip = aContent;
1.4350 + aContent->SetAttr(kNameSpaceID_None, aAtom, newValue, true);
1.4351 + MOZ_ASSERT(ShellIsAlive(weakShell), "pres shell was destroyed by scrolling");
1.4352 + if (!weakFrame.IsAlive()) {
1.4353 + return;
1.4354 + }
1.4355 +
1.4356 + if (mScrollbarActivity) {
1.4357 + nsRefPtr<ScrollbarActivity> scrollbarActivity(mScrollbarActivity);
1.4358 + scrollbarActivity->ActivityOccurred();
1.4359 + }
1.4360 +}
1.4361 +
1.4362 +static void
1.4363 +ReduceRadii(nscoord aXBorder, nscoord aYBorder,
1.4364 + nscoord& aXRadius, nscoord& aYRadius)
1.4365 +{
1.4366 + // In order to ensure that the inside edge of the border has no
1.4367 + // curvature, we need at least one of its radii to be zero.
1.4368 + if (aXRadius <= aXBorder || aYRadius <= aYBorder)
1.4369 + return;
1.4370 +
1.4371 + // For any corner where we reduce the radii, preserve the corner's shape.
1.4372 + double ratio = std::max(double(aXBorder) / aXRadius,
1.4373 + double(aYBorder) / aYRadius);
1.4374 + aXRadius *= ratio;
1.4375 + aYRadius *= ratio;
1.4376 +}
1.4377 +
1.4378 +/**
1.4379 + * Implement an override for nsIFrame::GetBorderRadii to ensure that
1.4380 + * the clipping region for the border radius does not clip the scrollbars.
1.4381 + *
1.4382 + * In other words, we require that the border radius be reduced until the
1.4383 + * inner border radius at the inner edge of the border is 0 wherever we
1.4384 + * have scrollbars.
1.4385 + */
1.4386 +bool
1.4387 +ScrollFrameHelper::GetBorderRadii(nscoord aRadii[8]) const
1.4388 +{
1.4389 + if (!mOuter->nsContainerFrame::GetBorderRadii(aRadii))
1.4390 + return false;
1.4391 +
1.4392 + // Since we can use GetActualScrollbarSizes (rather than
1.4393 + // GetDesiredScrollbarSizes) since this doesn't affect reflow, we
1.4394 + // probably should.
1.4395 + nsMargin sb = GetActualScrollbarSizes();
1.4396 + nsMargin border = mOuter->GetUsedBorder();
1.4397 +
1.4398 + if (sb.left > 0 || sb.top > 0) {
1.4399 + ReduceRadii(border.left, border.top,
1.4400 + aRadii[NS_CORNER_TOP_LEFT_X],
1.4401 + aRadii[NS_CORNER_TOP_LEFT_Y]);
1.4402 + }
1.4403 +
1.4404 + if (sb.top > 0 || sb.right > 0) {
1.4405 + ReduceRadii(border.right, border.top,
1.4406 + aRadii[NS_CORNER_TOP_RIGHT_X],
1.4407 + aRadii[NS_CORNER_TOP_RIGHT_Y]);
1.4408 + }
1.4409 +
1.4410 + if (sb.right > 0 || sb.bottom > 0) {
1.4411 + ReduceRadii(border.right, border.bottom,
1.4412 + aRadii[NS_CORNER_BOTTOM_RIGHT_X],
1.4413 + aRadii[NS_CORNER_BOTTOM_RIGHT_Y]);
1.4414 + }
1.4415 +
1.4416 + if (sb.bottom > 0 || sb.left > 0) {
1.4417 + ReduceRadii(border.left, border.bottom,
1.4418 + aRadii[NS_CORNER_BOTTOM_LEFT_X],
1.4419 + aRadii[NS_CORNER_BOTTOM_LEFT_Y]);
1.4420 + }
1.4421 +
1.4422 + return true;
1.4423 +}
1.4424 +
1.4425 +nsRect
1.4426 +ScrollFrameHelper::GetScrolledRect() const
1.4427 +{
1.4428 + nsRect result =
1.4429 + GetScrolledRectInternal(mScrolledFrame->GetScrollableOverflowRect(),
1.4430 + mScrollPort.Size());
1.4431 +
1.4432 + if (result.width < mScrollPort.width) {
1.4433 + NS_WARNING("Scrolled rect smaller than scrollport?");
1.4434 + }
1.4435 + if (result.height < mScrollPort.height) {
1.4436 + NS_WARNING("Scrolled rect smaller than scrollport?");
1.4437 + }
1.4438 + return result;
1.4439 +}
1.4440 +
1.4441 +nsRect
1.4442 +ScrollFrameHelper::GetScrolledRectInternal(const nsRect& aScrolledFrameOverflowArea,
1.4443 + const nsSize& aScrollPortSize) const
1.4444 +{
1.4445 + return nsLayoutUtils::GetScrolledRect(mScrolledFrame,
1.4446 + aScrolledFrameOverflowArea, aScrollPortSize,
1.4447 + IsLTR() ? NS_STYLE_DIRECTION_LTR : NS_STYLE_DIRECTION_RTL);
1.4448 +}
1.4449 +
1.4450 +nsMargin
1.4451 +ScrollFrameHelper::GetActualScrollbarSizes() const
1.4452 +{
1.4453 + nsRect r = mOuter->GetPaddingRect() - mOuter->GetPosition();
1.4454 +
1.4455 + return nsMargin(mScrollPort.y - r.y,
1.4456 + r.XMost() - mScrollPort.XMost(),
1.4457 + r.YMost() - mScrollPort.YMost(),
1.4458 + mScrollPort.x - r.x);
1.4459 +}
1.4460 +
1.4461 +void
1.4462 +ScrollFrameHelper::SetScrollbarVisibility(nsIFrame* aScrollbar, bool aVisible)
1.4463 +{
1.4464 + nsScrollbarFrame* scrollbar = do_QueryFrame(aScrollbar);
1.4465 + if (scrollbar) {
1.4466 + // See if we have a mediator.
1.4467 + nsIScrollbarMediator* mediator = scrollbar->GetScrollbarMediator();
1.4468 + if (mediator) {
1.4469 + // Inform the mediator of the visibility change.
1.4470 + mediator->VisibilityChanged(aVisible);
1.4471 + }
1.4472 + }
1.4473 +}
1.4474 +
1.4475 +nscoord
1.4476 +ScrollFrameHelper::GetCoordAttribute(nsIFrame* aBox, nsIAtom* aAtom,
1.4477 + nscoord aDefaultValue,
1.4478 + nscoord* aRangeStart,
1.4479 + nscoord* aRangeLength)
1.4480 +{
1.4481 + if (aBox) {
1.4482 + nsIContent* content = aBox->GetContent();
1.4483 +
1.4484 + nsAutoString value;
1.4485 + content->GetAttr(kNameSpaceID_None, aAtom, value);
1.4486 + if (!value.IsEmpty())
1.4487 + {
1.4488 + nsresult error;
1.4489 + // convert it to appunits
1.4490 + nscoord result = nsPresContext::CSSPixelsToAppUnits(value.ToInteger(&error));
1.4491 + nscoord halfPixel = nsPresContext::CSSPixelsToAppUnits(0.5f);
1.4492 + // Any nscoord value that would round to the attribute value when converted
1.4493 + // to CSS pixels is allowed.
1.4494 + *aRangeStart = result - halfPixel;
1.4495 + *aRangeLength = halfPixel*2 - 1;
1.4496 + return result;
1.4497 + }
1.4498 + }
1.4499 +
1.4500 + // Only this exact default value is allowed.
1.4501 + *aRangeStart = aDefaultValue;
1.4502 + *aRangeLength = 0;
1.4503 + return aDefaultValue;
1.4504 +}
1.4505 +
1.4506 +nsPresState*
1.4507 +ScrollFrameHelper::SaveState() const
1.4508 +{
1.4509 + nsIScrollbarMediator* mediator = do_QueryFrame(GetScrolledFrame());
1.4510 + if (mediator) {
1.4511 + // child handles its own scroll state, so don't bother saving state here
1.4512 + return nullptr;
1.4513 + }
1.4514 +
1.4515 + // Don't store a scroll state if we never have been scrolled or restored
1.4516 + // a previous scroll state.
1.4517 + if (!mHasBeenScrolled && !mDidHistoryRestore) {
1.4518 + return nullptr;
1.4519 + }
1.4520 +
1.4521 + nsPresState* state = new nsPresState();
1.4522 + // Save mRestorePos instead of our actual current scroll position, if it's
1.4523 + // valid and we haven't moved since the last update of mLastPos (same check
1.4524 + // that ScrollToRestoredPosition uses). This ensures if a reframe occurs
1.4525 + // while we're in the process of loading content to scroll to a restored
1.4526 + // position, we'll keep trying after the reframe.
1.4527 + nsPoint pt = GetLogicalScrollPosition();
1.4528 + if (mRestorePos.y != -1 && pt == mLastPos) {
1.4529 + pt = mRestorePos;
1.4530 + }
1.4531 + state->SetScrollState(pt);
1.4532 + state->SetResolution(mResolution);
1.4533 + return state;
1.4534 +}
1.4535 +
1.4536 +void
1.4537 +ScrollFrameHelper::RestoreState(nsPresState* aState)
1.4538 +{
1.4539 + mRestorePos = aState->GetScrollState();
1.4540 + mDidHistoryRestore = true;
1.4541 + mLastPos = mScrolledFrame ? GetLogicalScrollPosition() : nsPoint(0,0);
1.4542 + mResolution = aState->GetResolution();
1.4543 + mIsResolutionSet = true;
1.4544 +
1.4545 + if (mIsRoot) {
1.4546 + mOuter->PresContext()->PresShell()->SetResolution(mResolution.width, mResolution.height);
1.4547 + }
1.4548 +}
1.4549 +
1.4550 +void
1.4551 +ScrollFrameHelper::PostScrolledAreaEvent()
1.4552 +{
1.4553 + if (mScrolledAreaEvent.IsPending()) {
1.4554 + return;
1.4555 + }
1.4556 + mScrolledAreaEvent = new ScrolledAreaEvent(this);
1.4557 + nsContentUtils::AddScriptRunner(mScrolledAreaEvent.get());
1.4558 +}
1.4559 +
1.4560 +////////////////////////////////////////////////////////////////////////////////
1.4561 +// ScrolledArea change event dispatch
1.4562 +
1.4563 +NS_IMETHODIMP
1.4564 +ScrollFrameHelper::ScrolledAreaEvent::Run()
1.4565 +{
1.4566 + if (mHelper) {
1.4567 + mHelper->FireScrolledAreaEvent();
1.4568 + }
1.4569 + return NS_OK;
1.4570 +}
1.4571 +
1.4572 +void
1.4573 +ScrollFrameHelper::FireScrolledAreaEvent()
1.4574 +{
1.4575 + mScrolledAreaEvent.Forget();
1.4576 +
1.4577 + InternalScrollAreaEvent event(true, NS_SCROLLEDAREACHANGED, nullptr);
1.4578 + nsPresContext *prescontext = mOuter->PresContext();
1.4579 + nsIContent* content = mOuter->GetContent();
1.4580 +
1.4581 + event.mArea = mScrolledFrame->GetScrollableOverflowRectRelativeToParent();
1.4582 +
1.4583 + nsIDocument *doc = content->GetCurrentDoc();
1.4584 + if (doc) {
1.4585 + EventDispatcher::Dispatch(doc, prescontext, &event, nullptr);
1.4586 + }
1.4587 +}
1.4588 +
1.4589 +uint32_t
1.4590 +nsIScrollableFrame::GetPerceivedScrollingDirections() const
1.4591 +{
1.4592 + nscoord oneDevPixel = GetScrolledFrame()->PresContext()->AppUnitsPerDevPixel();
1.4593 + uint32_t directions = GetScrollbarVisibility();
1.4594 + nsRect scrollRange = GetScrollRange();
1.4595 + if (scrollRange.width >= oneDevPixel) {
1.4596 + directions |= HORIZONTAL;
1.4597 + }
1.4598 + if (scrollRange.height >= oneDevPixel) {
1.4599 + directions |= VERTICAL;
1.4600 + }
1.4601 + return directions;
1.4602 +}
