michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0:  * rendering object that is the root of the frame tree, which contains
michael@0:  * the document's scrollbars and contains fixed-positioned elements
michael@0:  */
michael@0: 
michael@0: #include "nsViewportFrame.h"
michael@0: #include "nsGkAtoms.h"
michael@0: #include "nsIScrollableFrame.h"
michael@0: #include "nsSubDocumentFrame.h"
michael@0: #include "nsAbsoluteContainingBlock.h"
michael@0: #include "GeckoProfiler.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: 
michael@0: nsIFrame*
michael@0: NS_NewViewportFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
michael@0: {
michael@0:   return new (aPresShell) ViewportFrame(aContext);
michael@0: }
michael@0: 
michael@0: NS_IMPL_FRAMEARENA_HELPERS(ViewportFrame)
michael@0: NS_QUERYFRAME_HEAD(ViewportFrame)
michael@0:   NS_QUERYFRAME_ENTRY(ViewportFrame)
michael@0: NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
michael@0: 
michael@0: void
michael@0: ViewportFrame::Init(nsIContent*      aContent,
michael@0:                     nsIFrame*        aParent,
michael@0:                     nsIFrame*        aPrevInFlow)
michael@0: {
michael@0:   Super::Init(aContent, aParent, aPrevInFlow);
michael@0: 
michael@0:   nsIFrame* parent = nsLayoutUtils::GetCrossDocParentFrame(this);
michael@0:   if (parent) {
michael@0:     nsFrameState state = parent->GetStateBits();
michael@0: 
michael@0:     mState |= state & (NS_FRAME_IN_POPUP);
michael@0:   }
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: ViewportFrame::SetInitialChildList(ChildListID     aListID,
michael@0:                                    nsFrameList&    aChildList)
michael@0: {
michael@0:   // See which child list to add the frames to
michael@0: #ifdef DEBUG
michael@0:   nsFrame::VerifyDirtyBitSet(aChildList);
michael@0: #endif
michael@0:   return nsContainerFrame::SetInitialChildList(aListID, aChildList);
michael@0: }
michael@0: 
michael@0: void
michael@0: ViewportFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
michael@0:                                 const nsRect&           aDirtyRect,
michael@0:                                 const nsDisplayListSet& aLists)
michael@0: {
michael@0:   PROFILER_LABEL("ViewportFrame", "BuildDisplayList");
michael@0:   nsIFrame* kid = mFrames.FirstChild();
michael@0:   if (!kid)
michael@0:     return;
michael@0: 
michael@0:   // make the kid's BorderBackground our own. This ensures that the canvas
michael@0:   // frame's background becomes our own background and therefore appears
michael@0:   // below negative z-index elements.
michael@0:   BuildDisplayListForChild(aBuilder, kid, aDirtyRect, aLists);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: ViewportFrame::AppendFrames(ChildListID     aListID,
michael@0:                             nsFrameList&    aFrameList)
michael@0: {
michael@0:   NS_ASSERTION(aListID == kPrincipalList ||
michael@0:                aListID == GetAbsoluteListID(), "unexpected child list");
michael@0:   NS_ASSERTION(aListID != GetAbsoluteListID() ||
michael@0:                GetChildList(aListID).IsEmpty(), "Shouldn't have any kids!");
michael@0:   return nsContainerFrame::AppendFrames(aListID, aFrameList);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: ViewportFrame::InsertFrames(ChildListID     aListID,
michael@0:                             nsIFrame*       aPrevFrame,
michael@0:                             nsFrameList&    aFrameList)
michael@0: {
michael@0:   NS_ASSERTION(aListID == kPrincipalList ||
michael@0:                aListID == GetAbsoluteListID(), "unexpected child list");
michael@0:   NS_ASSERTION(aListID != GetAbsoluteListID() ||
michael@0:                GetChildList(aListID).IsEmpty(), "Shouldn't have any kids!");
michael@0:   return nsContainerFrame::InsertFrames(aListID, aPrevFrame, aFrameList);
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: ViewportFrame::RemoveFrame(ChildListID     aListID,
michael@0:                            nsIFrame*       aOldFrame)
michael@0: {
michael@0:   NS_ASSERTION(aListID == kPrincipalList ||
michael@0:                aListID == GetAbsoluteListID(), "unexpected child list");
michael@0:   return nsContainerFrame::RemoveFrame(aListID, aOldFrame);
michael@0: }
michael@0: 
michael@0: /* virtual */ nscoord
michael@0: ViewportFrame::GetMinWidth(nsRenderingContext *aRenderingContext)
michael@0: {
michael@0:   nscoord result;
michael@0:   DISPLAY_MIN_WIDTH(this, result);
michael@0:   if (mFrames.IsEmpty())
michael@0:     result = 0;
michael@0:   else
michael@0:     result = mFrames.FirstChild()->GetMinWidth(aRenderingContext);
michael@0: 
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: /* virtual */ nscoord
michael@0: ViewportFrame::GetPrefWidth(nsRenderingContext *aRenderingContext)
michael@0: {
michael@0:   nscoord result;
michael@0:   DISPLAY_PREF_WIDTH(this, result);
michael@0:   if (mFrames.IsEmpty())
michael@0:     result = 0;
michael@0:   else
michael@0:     result = mFrames.FirstChild()->GetPrefWidth(aRenderingContext);
michael@0: 
michael@0:   return result;
michael@0: }
michael@0: 
michael@0: nsPoint
michael@0: ViewportFrame::AdjustReflowStateForScrollbars(nsHTMLReflowState* aReflowState) const
michael@0: {
michael@0:   // Get our prinicpal child frame and see if we're scrollable
michael@0:   nsIFrame* kidFrame = mFrames.FirstChild();
michael@0:   nsIScrollableFrame* scrollingFrame = do_QueryFrame(kidFrame);
michael@0: 
michael@0:   if (scrollingFrame) {
michael@0:     nsMargin scrollbars = scrollingFrame->GetActualScrollbarSizes();
michael@0:     aReflowState->SetComputedWidth(aReflowState->ComputedWidth() -
michael@0:                                    scrollbars.LeftRight());
michael@0:     aReflowState->AvailableWidth() -= scrollbars.LeftRight();
michael@0:     aReflowState->SetComputedHeightWithoutResettingResizeFlags(
michael@0:       aReflowState->ComputedHeight() - scrollbars.TopBottom());
michael@0:     return nsPoint(scrollbars.left, scrollbars.top);
michael@0:   }
michael@0:   return nsPoint(0, 0);
michael@0: }
michael@0: 
michael@0: nsRect
michael@0: ViewportFrame::AdjustReflowStateAsContainingBlock(nsHTMLReflowState* aReflowState) const
michael@0: {
michael@0: #ifdef DEBUG
michael@0:   nsPoint offset =
michael@0: #endif
michael@0:     AdjustReflowStateForScrollbars(aReflowState);
michael@0: 
michael@0:   NS_ASSERTION(GetAbsoluteContainingBlock()->GetChildList().IsEmpty() ||
michael@0:                (offset.x == 0 && offset.y == 0),
michael@0:                "We don't handle correct positioning of fixed frames with "
michael@0:                "scrollbars in odd positions");
michael@0: 
michael@0:   // If a scroll position clamping scroll-port size has been set, layout
michael@0:   // fixed position elements to this size instead of the computed size.
michael@0:   nsRect rect(0, 0, aReflowState->ComputedWidth(), aReflowState->ComputedHeight());
michael@0:   nsIPresShell* ps = PresContext()->PresShell();
michael@0:   if (ps->IsScrollPositionClampingScrollPortSizeSet()) {
michael@0:     rect.SizeTo(ps->GetScrollPositionClampingScrollPortSize());
michael@0:   }
michael@0: 
michael@0:   // Make sure content document fixed-position margins are respected.
michael@0:   rect.Deflate(ps->GetContentDocumentFixedPositionMargins());
michael@0:   return rect;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: ViewportFrame::Reflow(nsPresContext*           aPresContext,
michael@0:                       nsHTMLReflowMetrics&     aDesiredSize,
michael@0:                       const nsHTMLReflowState& aReflowState,
michael@0:                       nsReflowStatus&          aStatus)
michael@0: {
michael@0:   DO_GLOBAL_REFLOW_COUNT("ViewportFrame");
michael@0:   DISPLAY_REFLOW(aPresContext, this, aReflowState, aDesiredSize, aStatus);
michael@0:   NS_FRAME_TRACE_REFLOW_IN("ViewportFrame::Reflow");
michael@0: 
michael@0:   // Initialize OUT parameters
michael@0:   aStatus = NS_FRAME_COMPLETE;
michael@0: 
michael@0:   // Because |Reflow| sets mComputedHeight on the child to
michael@0:   // availableHeight.
michael@0:   AddStateBits(NS_FRAME_CONTAINS_RELATIVE_HEIGHT);
michael@0: 
michael@0:   // Set our size up front, since some parts of reflow depend on it
michael@0:   // being already set.  Note that the computed height may be
michael@0:   // unconstrained; that's ok.  Consumers should watch out for that.
michael@0:   SetSize(nsSize(aReflowState.ComputedWidth(), aReflowState.ComputedHeight()));
michael@0:  
michael@0:   // Reflow the main content first so that the placeholders of the
michael@0:   // fixed-position frames will be in the right places on an initial
michael@0:   // reflow.
michael@0:   nscoord kidHeight = 0;
michael@0: 
michael@0:   nsresult rv = NS_OK;
michael@0:   
michael@0:   if (mFrames.NotEmpty()) {
michael@0:     // Deal with a non-incremental reflow or an incremental reflow
michael@0:     // targeted at our one-and-only principal child frame.
michael@0:     if (aReflowState.ShouldReflowAllKids() ||
michael@0:         aReflowState.mFlags.mVResize ||
michael@0:         NS_SUBTREE_DIRTY(mFrames.FirstChild())) {
michael@0:       // Reflow our one-and-only principal child frame
michael@0:       nsIFrame*           kidFrame = mFrames.FirstChild();
michael@0:       nsHTMLReflowMetrics kidDesiredSize(aReflowState);
michael@0:       nsSize              availableSpace(aReflowState.AvailableWidth(),
michael@0:                                          aReflowState.AvailableHeight());
michael@0:       nsHTMLReflowState   kidReflowState(aPresContext, aReflowState,
michael@0:                                          kidFrame, availableSpace);
michael@0: 
michael@0:       // Reflow the frame
michael@0:       kidReflowState.SetComputedHeight(aReflowState.ComputedHeight());
michael@0:       rv = ReflowChild(kidFrame, aPresContext, kidDesiredSize, kidReflowState,
michael@0:                        0, 0, 0, aStatus);
michael@0:       kidHeight = kidDesiredSize.Height();
michael@0: 
michael@0:       FinishReflowChild(kidFrame, aPresContext, kidDesiredSize, nullptr, 0, 0, 0);
michael@0:     } else {
michael@0:       kidHeight = mFrames.FirstChild()->GetSize().height;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   NS_ASSERTION(aReflowState.AvailableWidth() != NS_UNCONSTRAINEDSIZE,
michael@0:                "shouldn't happen anymore");
michael@0: 
michael@0:   // Return the max size as our desired size
michael@0:   aDesiredSize.Width() = aReflowState.AvailableWidth();
michael@0:   // Being flowed initially at an unconstrained height means we should
michael@0:   // return our child's intrinsic size.
michael@0:   aDesiredSize.Height() = aReflowState.ComputedHeight() != NS_UNCONSTRAINEDSIZE
michael@0:                           ? aReflowState.ComputedHeight()
michael@0:                           : kidHeight;
michael@0:   aDesiredSize.SetOverflowAreasToDesiredBounds();
michael@0: 
michael@0:   if (mFrames.NotEmpty()) {
michael@0:     ConsiderChildOverflow(aDesiredSize.mOverflowAreas, mFrames.FirstChild());
michael@0:   }
michael@0: 
michael@0:   if (IsAbsoluteContainer()) {
michael@0:     // Make a copy of the reflow state and change the computed width and height
michael@0:     // to reflect the available space for the fixed items
michael@0:     nsHTMLReflowState reflowState(aReflowState);
michael@0: 
michael@0:     if (reflowState.AvailableHeight() == NS_UNCONSTRAINEDSIZE) {
michael@0:       // We have an intrinsic-height document with abs-pos/fixed-pos children.
michael@0:       // Set the available height and mComputedHeight to our chosen height.
michael@0:       reflowState.AvailableHeight() = aDesiredSize.Height();
michael@0:       // Not having border/padding simplifies things
michael@0:       NS_ASSERTION(reflowState.ComputedPhysicalBorderPadding() == nsMargin(0,0,0,0),
michael@0:                    "Viewports can't have border/padding");
michael@0:       reflowState.SetComputedHeight(aDesiredSize.Height());
michael@0:     }
michael@0: 
michael@0:     nsRect rect = AdjustReflowStateAsContainingBlock(&reflowState);
michael@0: 
michael@0:     // Just reflow all the fixed-pos frames.
michael@0:     rv = GetAbsoluteContainingBlock()->Reflow(this, aPresContext, reflowState, aStatus,
michael@0:                                               rect,
michael@0:                                               false, true, true, // XXX could be optimized
michael@0:                                               &aDesiredSize.mOverflowAreas);
michael@0:   }
michael@0: 
michael@0:   // If we were dirty then do a repaint
michael@0:   if (GetStateBits() & NS_FRAME_IS_DIRTY) {
michael@0:     InvalidateFrame();
michael@0:   }
michael@0: 
michael@0:   // Clipping is handled by the document container (e.g., nsSubDocumentFrame),
michael@0:   // so we don't need to change our overflow areas.
michael@0:   bool overflowChanged = FinishAndStoreOverflow(&aDesiredSize);
michael@0:   if (overflowChanged) {
michael@0:     // We may need to alert our container to get it to pick up the
michael@0:     // overflow change.
michael@0:     nsSubDocumentFrame* container = static_cast<nsSubDocumentFrame*>
michael@0:       (nsLayoutUtils::GetCrossDocParentFrame(this));
michael@0:     if (container && !container->ShouldClipSubdocument()) {
michael@0:       container->PresContext()->PresShell()->
michael@0:         FrameNeedsReflow(container, nsIPresShell::eResize, NS_FRAME_IS_DIRTY);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   NS_FRAME_TRACE_REFLOW_OUT("ViewportFrame::Reflow", aStatus);
michael@0:   NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aDesiredSize);
michael@0:   return rv; 
michael@0: }
michael@0: 
michael@0: nsIAtom*
michael@0: ViewportFrame::GetType() const
michael@0: {
michael@0:   return nsGkAtoms::viewportFrame;
michael@0: }
michael@0: 
michael@0: #ifdef DEBUG_FRAME_DUMP
michael@0: nsresult
michael@0: ViewportFrame::GetFrameName(nsAString& aResult) const
michael@0: {
michael@0:   return MakeFrameName(NS_LITERAL_STRING("Viewport"), aResult);
michael@0: }
michael@0: #endif