1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/layout/base/nsFrameTraversal.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,531 @@
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 +#include "nsCOMPtr.h"
1.9 +#include "nsGkAtoms.h"
1.10 +
1.11 +#include "nsFrameTraversal.h"
1.12 +#include "nsFrameList.h"
1.13 +#include "nsPlaceholderFrame.h"
1.14 +
1.15 +
1.16 +class nsFrameIterator : public nsIFrameEnumerator
1.17 +{
1.18 +public:
1.19 + typedef nsIFrame::ChildListID ChildListID;
1.20 +
1.21 + NS_DECL_ISUPPORTS
1.22 +
1.23 + virtual ~nsFrameIterator() {}
1.24 +
1.25 + virtual void First() MOZ_OVERRIDE;
1.26 + virtual void Next() MOZ_OVERRIDE;
1.27 + virtual nsIFrame* CurrentItem() MOZ_OVERRIDE;
1.28 + virtual bool IsDone() MOZ_OVERRIDE;
1.29 +
1.30 + virtual void Last() MOZ_OVERRIDE;
1.31 + virtual void Prev() MOZ_OVERRIDE;
1.32 +
1.33 + nsFrameIterator(nsPresContext* aPresContext, nsIFrame *aStart,
1.34 + nsIteratorType aType, bool aLockScroll, bool aFollowOOFs);
1.35 +
1.36 +protected:
1.37 + void setCurrent(nsIFrame *aFrame){mCurrent = aFrame;}
1.38 + nsIFrame *getCurrent(){return mCurrent;}
1.39 + nsIFrame *getStart(){return mStart;}
1.40 + nsIFrame *getLast(){return mLast;}
1.41 + void setLast(nsIFrame *aFrame){mLast = aFrame;}
1.42 + int8_t getOffEdge(){return mOffEdge;}
1.43 + void setOffEdge(int8_t aOffEdge){mOffEdge = aOffEdge;}
1.44 +
1.45 + /*
1.46 + Our own versions of the standard frame tree navigation
1.47 + methods, which, if the iterator is following out-of-flows,
1.48 + apply the following rules for placeholder frames:
1.49 +
1.50 + - If a frame HAS a placeholder frame, getting its parent
1.51 + gets the placeholder's parent.
1.52 +
1.53 + - If a frame's first child or next/prev sibling IS a
1.54 + placeholder frame, then we instead return the real frame.
1.55 +
1.56 + - If a frame HAS a placeholder frame, getting its next/prev
1.57 + sibling gets the placeholder frame's next/prev sibling.
1.58 +
1.59 + These are all applied recursively to support multiple levels of
1.60 + placeholders.
1.61 + */
1.62 +
1.63 + nsIFrame* GetParentFrame(nsIFrame* aFrame);
1.64 + // like GetParentFrame but returns null once a popup frame is reached
1.65 + nsIFrame* GetParentFrameNotPopup(nsIFrame* aFrame);
1.66 +
1.67 + nsIFrame* GetFirstChild(nsIFrame* aFrame);
1.68 + nsIFrame* GetLastChild(nsIFrame* aFrame);
1.69 +
1.70 + nsIFrame* GetNextSibling(nsIFrame* aFrame);
1.71 + nsIFrame* GetPrevSibling(nsIFrame* aFrame);
1.72 +
1.73 + /*
1.74 + These methods are overridden by the bidi visual iterator to have the
1.75 + semantics of "get first child in visual order", "get last child in visual
1.76 + order", "get next sibling in visual order" and "get previous sibling in visual
1.77 + order".
1.78 + */
1.79 +
1.80 + virtual nsIFrame* GetFirstChildInner(nsIFrame* aFrame);
1.81 + virtual nsIFrame* GetLastChildInner(nsIFrame* aFrame);
1.82 +
1.83 + virtual nsIFrame* GetNextSiblingInner(nsIFrame* aFrame);
1.84 + virtual nsIFrame* GetPrevSiblingInner(nsIFrame* aFrame);
1.85 +
1.86 + nsIFrame* GetPlaceholderFrame(nsIFrame* aFrame);
1.87 + bool IsPopupFrame(nsIFrame* aFrame);
1.88 +
1.89 + nsPresContext* const mPresContext;
1.90 + const bool mLockScroll;
1.91 + const bool mFollowOOFs;
1.92 + const nsIteratorType mType;
1.93 +
1.94 +private:
1.95 + nsIFrame* const mStart;
1.96 + nsIFrame* mCurrent;
1.97 + nsIFrame* mLast; //the last one that was in current;
1.98 + int8_t mOffEdge; //0= no -1 to far prev, 1 to far next;
1.99 +};
1.100 +
1.101 +
1.102 +
1.103 +// Bidi visual iterator
1.104 +class nsVisualIterator: public nsFrameIterator
1.105 +{
1.106 +public:
1.107 + nsVisualIterator(nsPresContext* aPresContext, nsIFrame *aStart,
1.108 + nsIteratorType aType, bool aLockScroll, bool aFollowOOFs) :
1.109 + nsFrameIterator(aPresContext, aStart, aType, aLockScroll, aFollowOOFs) {}
1.110 +
1.111 +protected:
1.112 + nsIFrame* GetFirstChildInner(nsIFrame* aFrame) MOZ_OVERRIDE;
1.113 + nsIFrame* GetLastChildInner(nsIFrame* aFrame) MOZ_OVERRIDE;
1.114 +
1.115 + nsIFrame* GetNextSiblingInner(nsIFrame* aFrame) MOZ_OVERRIDE;
1.116 + nsIFrame* GetPrevSiblingInner(nsIFrame* aFrame) MOZ_OVERRIDE;
1.117 +};
1.118 +
1.119 +/************IMPLEMENTATIONS**************/
1.120 +
1.121 +nsresult NS_CreateFrameTraversal(nsIFrameTraversal** aResult)
1.122 +{
1.123 + NS_ENSURE_ARG_POINTER(aResult);
1.124 + *aResult = nullptr;
1.125 +
1.126 + nsCOMPtr<nsIFrameTraversal> t(new nsFrameTraversal());
1.127 +
1.128 + *aResult = t;
1.129 + NS_ADDREF(*aResult);
1.130 +
1.131 + return NS_OK;
1.132 +}
1.133 +
1.134 +nsresult
1.135 +NS_NewFrameTraversal(nsIFrameEnumerator **aEnumerator,
1.136 + nsPresContext* aPresContext,
1.137 + nsIFrame *aStart,
1.138 + nsIteratorType aType,
1.139 + bool aVisual,
1.140 + bool aLockInScrollView,
1.141 + bool aFollowOOFs)
1.142 +{
1.143 + if (!aEnumerator || !aStart)
1.144 + return NS_ERROR_NULL_POINTER;
1.145 +
1.146 + if (aFollowOOFs) {
1.147 + aStart = nsPlaceholderFrame::GetRealFrameFor(aStart);
1.148 + }
1.149 +
1.150 + nsCOMPtr<nsIFrameEnumerator> trav;
1.151 + if (aVisual) {
1.152 + trav = new nsVisualIterator(aPresContext, aStart, aType,
1.153 + aLockInScrollView, aFollowOOFs);
1.154 + } else {
1.155 + trav = new nsFrameIterator(aPresContext, aStart, aType,
1.156 + aLockInScrollView, aFollowOOFs);
1.157 + }
1.158 + trav.forget(aEnumerator);
1.159 + return NS_OK;
1.160 +}
1.161 +
1.162 +
1.163 +nsFrameTraversal::nsFrameTraversal()
1.164 +{
1.165 +}
1.166 +
1.167 +nsFrameTraversal::~nsFrameTraversal()
1.168 +{
1.169 +}
1.170 +
1.171 +NS_IMPL_ISUPPORTS(nsFrameTraversal,nsIFrameTraversal)
1.172 +
1.173 +NS_IMETHODIMP
1.174 + nsFrameTraversal::NewFrameTraversal(nsIFrameEnumerator **aEnumerator,
1.175 + nsPresContext* aPresContext,
1.176 + nsIFrame *aStart,
1.177 + int32_t aType,
1.178 + bool aVisual,
1.179 + bool aLockInScrollView,
1.180 + bool aFollowOOFs)
1.181 +{
1.182 + return NS_NewFrameTraversal(aEnumerator, aPresContext, aStart,
1.183 + static_cast<nsIteratorType>(aType),
1.184 + aVisual, aLockInScrollView, aFollowOOFs);
1.185 +}
1.186 +
1.187 +// nsFrameIterator implementation
1.188 +
1.189 +NS_IMPL_ISUPPORTS(nsFrameIterator, nsIFrameEnumerator)
1.190 +
1.191 +nsFrameIterator::nsFrameIterator(nsPresContext* aPresContext, nsIFrame *aStart,
1.192 + nsIteratorType aType, bool aLockInScrollView,
1.193 + bool aFollowOOFs)
1.194 +: mPresContext(aPresContext),
1.195 + mLockScroll(aLockInScrollView),
1.196 + mFollowOOFs(aFollowOOFs),
1.197 + mType(aType),
1.198 + mStart(aStart),
1.199 + mCurrent(aStart),
1.200 + mLast(aStart),
1.201 + mOffEdge(0)
1.202 +{
1.203 + MOZ_ASSERT(!aFollowOOFs || aStart->GetType() != nsGkAtoms::placeholderFrame,
1.204 + "Caller should have resolved placeholder frame");
1.205 +}
1.206 +
1.207 +
1.208 +
1.209 +nsIFrame*
1.210 +nsFrameIterator::CurrentItem()
1.211 +{
1.212 + if (mOffEdge)
1.213 + return nullptr;
1.214 +
1.215 + return mCurrent;
1.216 +}
1.217 +
1.218 +
1.219 +
1.220 +bool
1.221 +nsFrameIterator::IsDone()
1.222 +{
1.223 + return mOffEdge != 0;
1.224 +}
1.225 +
1.226 +void
1.227 +nsFrameIterator::First()
1.228 +{
1.229 + mCurrent = mStart;
1.230 +}
1.231 +
1.232 +static bool
1.233 +IsRootFrame(nsIFrame* aFrame)
1.234 +{
1.235 + nsIAtom* atom = aFrame->GetType();
1.236 + return (atom == nsGkAtoms::canvasFrame) ||
1.237 + (atom == nsGkAtoms::rootFrame);
1.238 +}
1.239 +
1.240 +void
1.241 +nsFrameIterator::Last()
1.242 +{
1.243 + nsIFrame* result;
1.244 + nsIFrame* parent = getCurrent();
1.245 + // If the current frame is a popup, don't move farther up the tree.
1.246 + // Otherwise, get the nearest root frame or popup.
1.247 + if (parent->GetType() != nsGkAtoms::menuPopupFrame) {
1.248 + while (!IsRootFrame(parent) && (result = GetParentFrameNotPopup(parent)))
1.249 + parent = result;
1.250 + }
1.251 +
1.252 + while ((result = GetLastChild(parent))) {
1.253 + parent = result;
1.254 + }
1.255 +
1.256 + setCurrent(parent);
1.257 + if (!parent)
1.258 + setOffEdge(1);
1.259 +}
1.260 +
1.261 +void
1.262 +nsFrameIterator::Next()
1.263 +{
1.264 + // recursive-oid method to get next frame
1.265 + nsIFrame *result = nullptr;
1.266 + nsIFrame *parent = getCurrent();
1.267 + if (!parent)
1.268 + parent = getLast();
1.269 +
1.270 + if (mType == eLeaf) {
1.271 + // Drill down to first leaf
1.272 + while ((result = GetFirstChild(parent))) {
1.273 + parent = result;
1.274 + }
1.275 + } else if (mType == ePreOrder) {
1.276 + result = GetFirstChild(parent);
1.277 + if (result)
1.278 + parent = result;
1.279 + }
1.280 +
1.281 + if (parent != getCurrent()) {
1.282 + result = parent;
1.283 + } else {
1.284 + while (parent) {
1.285 + result = GetNextSibling(parent);
1.286 + if (result) {
1.287 + if (mType != ePreOrder) {
1.288 + parent = result;
1.289 + while ((result = GetFirstChild(parent))) {
1.290 + parent = result;
1.291 + }
1.292 + result = parent;
1.293 + }
1.294 + break;
1.295 + }
1.296 + else {
1.297 + result = GetParentFrameNotPopup(parent);
1.298 + if (!result || IsRootFrame(result) ||
1.299 + (mLockScroll && result->GetType() == nsGkAtoms::scrollFrame)) {
1.300 + result = nullptr;
1.301 + break;
1.302 + }
1.303 + if (mType == ePostOrder)
1.304 + break;
1.305 + parent = result;
1.306 + }
1.307 + }
1.308 + }
1.309 +
1.310 + setCurrent(result);
1.311 + if (!result) {
1.312 + setOffEdge(1);
1.313 + setLast(parent);
1.314 + }
1.315 +}
1.316 +
1.317 +void
1.318 +nsFrameIterator::Prev()
1.319 +{
1.320 + // recursive-oid method to get prev frame
1.321 + nsIFrame *result = nullptr;
1.322 + nsIFrame *parent = getCurrent();
1.323 + if (!parent)
1.324 + parent = getLast();
1.325 +
1.326 + if (mType == eLeaf) {
1.327 + // Drill down to last leaf
1.328 + while ((result = GetLastChild(parent))) {
1.329 + parent = result;
1.330 + }
1.331 + } else if (mType == ePostOrder) {
1.332 + result = GetLastChild(parent);
1.333 + if (result)
1.334 + parent = result;
1.335 + }
1.336 +
1.337 + if (parent != getCurrent()) {
1.338 + result = parent;
1.339 + } else {
1.340 + while (parent) {
1.341 + result = GetPrevSibling(parent);
1.342 + if (result) {
1.343 + if (mType != ePostOrder) {
1.344 + parent = result;
1.345 + while ((result = GetLastChild(parent))) {
1.346 + parent = result;
1.347 + }
1.348 + result = parent;
1.349 + }
1.350 + break;
1.351 + } else {
1.352 + result = GetParentFrameNotPopup(parent);
1.353 + if (!result || IsRootFrame(result) ||
1.354 + (mLockScroll && result->GetType() == nsGkAtoms::scrollFrame)) {
1.355 + result = nullptr;
1.356 + break;
1.357 + }
1.358 + if (mType == ePreOrder)
1.359 + break;
1.360 + parent = result;
1.361 + }
1.362 + }
1.363 + }
1.364 +
1.365 + setCurrent(result);
1.366 + if (!result) {
1.367 + setOffEdge(-1);
1.368 + setLast(parent);
1.369 + }
1.370 +}
1.371 +
1.372 +nsIFrame*
1.373 +nsFrameIterator::GetParentFrame(nsIFrame* aFrame)
1.374 +{
1.375 + if (mFollowOOFs)
1.376 + aFrame = GetPlaceholderFrame(aFrame);
1.377 + if (aFrame)
1.378 + return aFrame->GetParent();
1.379 +
1.380 + return nullptr;
1.381 +}
1.382 +
1.383 +nsIFrame*
1.384 +nsFrameIterator::GetParentFrameNotPopup(nsIFrame* aFrame)
1.385 +{
1.386 + if (mFollowOOFs)
1.387 + aFrame = GetPlaceholderFrame(aFrame);
1.388 + if (aFrame) {
1.389 + nsIFrame* parent = aFrame->GetParent();
1.390 + if (!IsPopupFrame(parent))
1.391 + return parent;
1.392 + }
1.393 +
1.394 + return nullptr;
1.395 +}
1.396 +
1.397 +nsIFrame*
1.398 +nsFrameIterator::GetFirstChild(nsIFrame* aFrame)
1.399 +{
1.400 + nsIFrame* result = GetFirstChildInner(aFrame);
1.401 + if (mLockScroll && result && result->GetType() == nsGkAtoms::scrollFrame)
1.402 + return nullptr;
1.403 + if (result && mFollowOOFs) {
1.404 + result = nsPlaceholderFrame::GetRealFrameFor(result);
1.405 +
1.406 + if (IsPopupFrame(result))
1.407 + result = GetNextSibling(result);
1.408 + }
1.409 + return result;
1.410 +}
1.411 +
1.412 +nsIFrame*
1.413 +nsFrameIterator::GetLastChild(nsIFrame* aFrame)
1.414 +{
1.415 + nsIFrame* result = GetLastChildInner(aFrame);
1.416 + if (mLockScroll && result && result->GetType() == nsGkAtoms::scrollFrame)
1.417 + return nullptr;
1.418 + if (result && mFollowOOFs) {
1.419 + result = nsPlaceholderFrame::GetRealFrameFor(result);
1.420 +
1.421 + if (IsPopupFrame(result))
1.422 + result = GetPrevSibling(result);
1.423 + }
1.424 + return result;
1.425 +}
1.426 +
1.427 +nsIFrame*
1.428 +nsFrameIterator::GetNextSibling(nsIFrame* aFrame)
1.429 +{
1.430 + nsIFrame* result = nullptr;
1.431 + if (mFollowOOFs)
1.432 + aFrame = GetPlaceholderFrame(aFrame);
1.433 + if (aFrame) {
1.434 + result = GetNextSiblingInner(aFrame);
1.435 + if (result && mFollowOOFs)
1.436 + result = nsPlaceholderFrame::GetRealFrameFor(result);
1.437 + }
1.438 +
1.439 + if (mFollowOOFs && IsPopupFrame(result))
1.440 + result = GetNextSibling(result);
1.441 +
1.442 + return result;
1.443 +}
1.444 +
1.445 +nsIFrame*
1.446 +nsFrameIterator::GetPrevSibling(nsIFrame* aFrame)
1.447 +{
1.448 + nsIFrame* result = nullptr;
1.449 + if (mFollowOOFs)
1.450 + aFrame = GetPlaceholderFrame(aFrame);
1.451 + if (aFrame) {
1.452 + result = GetPrevSiblingInner(aFrame);
1.453 + if (result && mFollowOOFs)
1.454 + result = nsPlaceholderFrame::GetRealFrameFor(result);
1.455 + }
1.456 +
1.457 + if (mFollowOOFs && IsPopupFrame(result))
1.458 + result = GetPrevSibling(result);
1.459 +
1.460 + return result;
1.461 +}
1.462 +
1.463 +nsIFrame*
1.464 +nsFrameIterator::GetFirstChildInner(nsIFrame* aFrame) {
1.465 + return aFrame->GetFirstPrincipalChild();
1.466 +}
1.467 +
1.468 +nsIFrame*
1.469 +nsFrameIterator::GetLastChildInner(nsIFrame* aFrame) {
1.470 + return aFrame->PrincipalChildList().LastChild();
1.471 +}
1.472 +
1.473 +nsIFrame*
1.474 +nsFrameIterator::GetNextSiblingInner(nsIFrame* aFrame) {
1.475 + return aFrame->GetNextSibling();
1.476 +}
1.477 +
1.478 +nsIFrame*
1.479 +nsFrameIterator::GetPrevSiblingInner(nsIFrame* aFrame) {
1.480 + return aFrame->GetPrevSibling();
1.481 +}
1.482 +
1.483 +
1.484 +nsIFrame*
1.485 +nsFrameIterator::GetPlaceholderFrame(nsIFrame* aFrame)
1.486 +{
1.487 + nsIFrame* result = aFrame;
1.488 + nsIPresShell *presShell = mPresContext->GetPresShell();
1.489 + if (presShell) {
1.490 + nsIFrame* placeholder = presShell->GetPlaceholderFrameFor(aFrame);
1.491 + if (placeholder)
1.492 + result = placeholder;
1.493 + }
1.494 +
1.495 + if (result != aFrame)
1.496 + result = GetPlaceholderFrame(result);
1.497 +
1.498 + return result;
1.499 +}
1.500 +
1.501 +bool
1.502 +nsFrameIterator::IsPopupFrame(nsIFrame* aFrame)
1.503 +{
1.504 + return (aFrame &&
1.505 + aFrame->StyleDisplay()->mDisplay == NS_STYLE_DISPLAY_POPUP);
1.506 +}
1.507 +
1.508 +// nsVisualIterator implementation
1.509 +
1.510 +nsIFrame*
1.511 +nsVisualIterator::GetFirstChildInner(nsIFrame* aFrame) {
1.512 + return aFrame->PrincipalChildList().GetNextVisualFor(nullptr);
1.513 +}
1.514 +
1.515 +nsIFrame*
1.516 +nsVisualIterator::GetLastChildInner(nsIFrame* aFrame) {
1.517 + return aFrame->PrincipalChildList().GetPrevVisualFor(nullptr);
1.518 +}
1.519 +
1.520 +nsIFrame*
1.521 +nsVisualIterator::GetNextSiblingInner(nsIFrame* aFrame) {
1.522 + nsIFrame* parent = GetParentFrame(aFrame);
1.523 + if (!parent)
1.524 + return nullptr;
1.525 + return parent->PrincipalChildList().GetNextVisualFor(aFrame);
1.526 +}
1.527 +
1.528 +nsIFrame*
1.529 +nsVisualIterator::GetPrevSiblingInner(nsIFrame* aFrame) {
1.530 + nsIFrame* parent = GetParentFrame(aFrame);
1.531 + if (!parent)
1.532 + return nullptr;
1.533 + return parent->PrincipalChildList().GetPrevVisualFor(aFrame);
1.534 +}
