/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ /** * Code responsible for managing style changes: tracking what style * changes need to happen, scheduling them, and doing them. */ #include "RestyleManager.h" #include "nsLayoutUtils.h" #include "GeckoProfiler.h" #include "nsStyleChangeList.h" #include "nsRuleProcessorData.h" #include "nsStyleUtil.h" #include "nsCSSFrameConstructor.h" #include "nsSVGEffects.h" #include "nsCSSRendering.h" #include "nsAnimationManager.h" #include "nsTransitionManager.h" #include "nsViewManager.h" #include "nsRenderingContext.h" #include "nsSVGIntegrationUtils.h" #include "nsCSSAnonBoxes.h" #include "nsContainerFrame.h" #include "nsPlaceholderFrame.h" #include "nsBlockFrame.h" #include "nsViewportFrame.h" #include "nsSVGTextFrame2.h" #include "nsSVGTextPathFrame.h" #include "StickyScrollContainer.h" #include "nsIRootBox.h" #include "nsIDOMMutationEvent.h" #include "nsContentUtils.h" #include "nsIFrameInlines.h" #ifdef ACCESSIBILITY #include "nsAccessibilityService.h" #endif namespace mozilla { RestyleManager::RestyleManager(nsPresContext* aPresContext) : mPresContext(aPresContext) , mRebuildAllStyleData(false) , mObservingRefreshDriver(false) , mInStyleRefresh(false) , mHoverGeneration(0) , mRebuildAllExtraHint(nsChangeHint(0)) , mAnimationGeneration(0) , mPendingRestyles(ELEMENT_HAS_PENDING_RESTYLE | ELEMENT_IS_POTENTIAL_RESTYLE_ROOT) , mPendingAnimationRestyles(ELEMENT_HAS_PENDING_ANIMATION_RESTYLE | ELEMENT_IS_POTENTIAL_ANIMATION_RESTYLE_ROOT) { mPendingRestyles.Init(this); mPendingAnimationRestyles.Init(this); } void RestyleManager::NotifyDestroyingFrame(nsIFrame* aFrame) { mOverflowChangedTracker.RemoveFrame(aFrame); } #ifdef DEBUG // To ensure that the functions below are only called within // |ApplyRenderingChangeToTree|. static bool gInApplyRenderingChangeToTree = false; #endif static void DoApplyRenderingChangeToTree(nsIFrame* aFrame, nsChangeHint aChange); /** * Sync views on aFrame and all of aFrame's descendants (following placeholders), * if aChange has nsChangeHint_SyncFrameView. * Calls DoApplyRenderingChangeToTree on all aFrame's out-of-flow descendants * (following placeholders), if aChange has nsChangeHint_RepaintFrame. * aFrame should be some combination of nsChangeHint_SyncFrameView and * nsChangeHint_RepaintFrame and nsChangeHint_UpdateOpacityLayer, nothing else. */ static void SyncViewsAndInvalidateDescendants(nsIFrame* aFrame, nsChangeHint aChange) { NS_PRECONDITION(gInApplyRenderingChangeToTree, "should only be called within ApplyRenderingChangeToTree"); NS_ASSERTION(aChange == (aChange & (nsChangeHint_RepaintFrame | nsChangeHint_SyncFrameView | nsChangeHint_UpdateOpacityLayer)), "Invalid change flag"); nsView* view = aFrame->GetView(); if (view) { if (aChange & nsChangeHint_SyncFrameView) { nsContainerFrame::SyncFrameViewProperties(aFrame->PresContext(), aFrame, nullptr, view); } } nsIFrame::ChildListIterator lists(aFrame); for (; !lists.IsDone(); lists.Next()) { nsFrameList::Enumerator childFrames(lists.CurrentList()); for (; !childFrames.AtEnd(); childFrames.Next()) { nsIFrame* child = childFrames.get(); if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW)) { // only do frames that don't have placeholders if (nsGkAtoms::placeholderFrame == child->GetType()) { // do the out-of-flow frame and its continuations nsIFrame* outOfFlowFrame = nsPlaceholderFrame::GetRealFrameForPlaceholder(child); DoApplyRenderingChangeToTree(outOfFlowFrame, aChange); } else if (lists.CurrentID() == nsIFrame::kPopupList) { DoApplyRenderingChangeToTree(child, aChange); } else { // regular frame SyncViewsAndInvalidateDescendants(child, aChange); } } } } } /** * To handle nsChangeHint_ChildrenOnlyTransform we must iterate over the child * frames of the SVG frame concerned. This helper function is used to find that * SVG frame when we encounter nsChangeHint_ChildrenOnlyTransform to ensure * that we iterate over the intended children, since sometimes we end up * handling that hint while processing hints for one of the SVG frame's * ancestor frames. * * The reason that we sometimes end up trying to process the hint for an * ancestor of the SVG frame that the hint is intended for is due to the way we * process restyle events. ApplyRenderingChangeToTree adjusts the frame from * the restyled element's principle frame to one of its ancestor frames based * on what nsCSSRendering::FindBackground returns, since the background style * may have been propagated up to an ancestor frame. Processing hints using an * ancestor frame is fine in general, but nsChangeHint_ChildrenOnlyTransform is * a special case since it is intended to update the children of a specific * frame. */ static nsIFrame* GetFrameForChildrenOnlyTransformHint(nsIFrame *aFrame) { if (aFrame->GetType() == nsGkAtoms::viewportFrame) { // This happens if the root- is fixed positioned, in which case we // can't use aFrame->GetContent() to find the primary frame, since // GetContent() returns nullptr for ViewportFrame. aFrame = aFrame->GetFirstPrincipalChild(); } // For an nsHTMLScrollFrame, this will get the SVG frame that has the // children-only transforms: aFrame = aFrame->GetContent()->GetPrimaryFrame(); if (aFrame->GetType() == nsGkAtoms::svgOuterSVGFrame) { aFrame = aFrame->GetFirstPrincipalChild(); NS_ABORT_IF_FALSE(aFrame->GetType() == nsGkAtoms::svgOuterSVGAnonChildFrame, "Where is the nsSVGOuterSVGFrame's anon child??"); } NS_ABORT_IF_FALSE(aFrame->IsFrameOfType(nsIFrame::eSVG | nsIFrame::eSVGContainer), "Children-only transforms only expected on SVG frames"); return aFrame; } static void DoApplyRenderingChangeToTree(nsIFrame* aFrame, nsChangeHint aChange) { NS_PRECONDITION(gInApplyRenderingChangeToTree, "should only be called within ApplyRenderingChangeToTree"); for ( ; aFrame; aFrame = nsLayoutUtils::GetNextContinuationOrSpecialSibling(aFrame)) { // Invalidate and sync views on all descendant frames, following placeholders. // We don't need to update transforms in SyncViewsAndInvalidateDescendants, because // there can't be any out-of-flows or popups that need to be transformed; // all out-of-flow descendants of the transformed element must also be // descendants of the transformed frame. SyncViewsAndInvalidateDescendants(aFrame, nsChangeHint(aChange & (nsChangeHint_RepaintFrame | nsChangeHint_SyncFrameView | nsChangeHint_UpdateOpacityLayer))); // This must be set to true if the rendering change needs to // invalidate content. If it's false, a composite-only paint // (empty transaction) will be scheduled. bool needInvalidatingPaint = false; // if frame has view, will already be invalidated if (aChange & nsChangeHint_RepaintFrame) { // Note that this whole block will be skipped when painting is suppressed // (due to our caller ApplyRendingChangeToTree() discarding the // nsChangeHint_RepaintFrame hint). If you add handling for any other // hints within this block, be sure that they too should be ignored when // painting is suppressed. needInvalidatingPaint = true; aFrame->InvalidateFrameSubtree(); if (aChange & nsChangeHint_UpdateEffects && aFrame->IsFrameOfType(nsIFrame::eSVG) && !(aFrame->GetStateBits() & NS_STATE_IS_OUTER_SVG)) { // Need to update our overflow rects: nsSVGUtils::ScheduleReflowSVG(aFrame); } } if (aChange & nsChangeHint_UpdateTextPath) { if (aFrame->GetType() == nsGkAtoms::svgTextPathFrame) { // Invalidate and reflow the entire nsSVGTextFrame: static_cast(aFrame)->NotifyGlyphMetricsChange(); } else if (aFrame->IsSVGText()) { // Invalidate and reflow the entire nsSVGTextFrame2: NS_ASSERTION(aFrame->GetContent()->IsSVG(nsGkAtoms::textPath), "expected frame for a element"); nsIFrame* text = nsLayoutUtils::GetClosestFrameOfType( aFrame, nsGkAtoms::svgTextFrame2); NS_ASSERTION(text, "expected to find an ancestor nsSVGTextFrame2"); static_cast(text)->NotifyGlyphMetricsChange(); } else { NS_ABORT_IF_FALSE(false, "unexpected frame got " "nsChangeHint_UpdateTextPath"); } } if (aChange & nsChangeHint_UpdateOpacityLayer) { // FIXME/bug 796697: we can get away with empty transactions for // opacity updates in many cases. needInvalidatingPaint = true; aFrame->MarkLayersActive(nsChangeHint_UpdateOpacityLayer); if (nsSVGIntegrationUtils::UsingEffectsForFrame(aFrame)) { // SVG effects paints the opacity without using // nsDisplayOpacity. We need to invalidate manually. aFrame->InvalidateFrameSubtree(); } } if ((aChange & nsChangeHint_UpdateTransformLayer) && aFrame->IsTransformed()) { aFrame->MarkLayersActive(nsChangeHint_UpdateTransformLayer); // If we're not already going to do an invalidating paint, see // if we can get away with only updating the transform on a // layer for this frame, and not scheduling an invalidating // paint. if (!needInvalidatingPaint) { needInvalidatingPaint |= !aFrame->TryUpdateTransformOnly(); } } if (aChange & nsChangeHint_ChildrenOnlyTransform) { needInvalidatingPaint = true; nsIFrame* childFrame = GetFrameForChildrenOnlyTransformHint(aFrame)->GetFirstPrincipalChild(); for ( ; childFrame; childFrame = childFrame->GetNextSibling()) { childFrame->MarkLayersActive(nsChangeHint_UpdateTransformLayer); } } aFrame->SchedulePaint(needInvalidatingPaint ? nsIFrame::PAINT_DEFAULT : nsIFrame::PAINT_COMPOSITE_ONLY); } } static void ApplyRenderingChangeToTree(nsPresContext* aPresContext, nsIFrame* aFrame, nsChangeHint aChange) { // We check StyleDisplay()->HasTransform() in addition to checking // IsTransformed() since we can get here for some frames that don't support // CSS transforms. NS_ASSERTION(!(aChange & nsChangeHint_UpdateTransformLayer) || aFrame->IsTransformed() || aFrame->StyleDisplay()->HasTransformStyle(), "Unexpected UpdateTransformLayer hint"); nsIPresShell *shell = aPresContext->PresShell(); if (shell->IsPaintingSuppressed()) { // Don't allow synchronous rendering changes when painting is turned off. aChange = NS_SubtractHint(aChange, nsChangeHint_RepaintFrame); if (!aChange) { return; } } // If the frame's background is propagated to an ancestor, walk up to // that ancestor. nsStyleContext *bgSC; while (!nsCSSRendering::FindBackground(aFrame, &bgSC)) { aFrame = aFrame->GetParent(); NS_ASSERTION(aFrame, "root frame must paint"); } // Trigger rendering updates by damaging this frame and any // continuations of this frame. // XXX this needs to detect the need for a view due to an opacity change and deal with it... #ifdef DEBUG gInApplyRenderingChangeToTree = true; #endif DoApplyRenderingChangeToTree(aFrame, aChange); #ifdef DEBUG gInApplyRenderingChangeToTree = false; #endif } bool RestyleManager::RecomputePosition(nsIFrame* aFrame) { // Don't process position changes on table frames, since we already handle // the dynamic position change on the outer table frame, and the reflow-based // fallback code path also ignores positions on inner table frames. if (aFrame->GetType() == nsGkAtoms::tableFrame) { return true; } // Don't process position changes on frames which have views or the ones which // have a view somewhere in their descendants, because the corresponding view // needs to be repositioned properly as well. if (aFrame->HasView() || (aFrame->GetStateBits() & NS_FRAME_HAS_CHILD_WITH_VIEW)) { StyleChangeReflow(aFrame, nsChangeHint_NeedReflow); return false; } const nsStyleDisplay* display = aFrame->StyleDisplay(); // Changes to the offsets of a non-positioned element can safely be ignored. if (display->mPosition == NS_STYLE_POSITION_STATIC) { return true; } aFrame->SchedulePaint(); // For relative positioning, we can simply update the frame rect if (display->IsRelativelyPositionedStyle()) { switch (display->mDisplay) { case NS_STYLE_DISPLAY_TABLE_CAPTION: case NS_STYLE_DISPLAY_TABLE_CELL: case NS_STYLE_DISPLAY_TABLE_ROW: case NS_STYLE_DISPLAY_TABLE_ROW_GROUP: case NS_STYLE_DISPLAY_TABLE_HEADER_GROUP: case NS_STYLE_DISPLAY_TABLE_FOOTER_GROUP: case NS_STYLE_DISPLAY_TABLE_COLUMN: case NS_STYLE_DISPLAY_TABLE_COLUMN_GROUP: // We don't currently support relative positioning of inner // table elements. If we apply offsets to things we haven't // previously offset, we'll get confused. So bail. return true; default: break; } // Move the frame if (display->mPosition == NS_STYLE_POSITION_STICKY) { // Update sticky positioning for an entire element at once when // RecomputePosition is called with the first continuation in a chain. StickyScrollContainer::ComputeStickyOffsets(aFrame); StickyScrollContainer* ssc = StickyScrollContainer::GetStickyScrollContainerForFrame(aFrame); if (ssc) { ssc->PositionContinuations(aFrame); } } else { MOZ_ASSERT(NS_STYLE_POSITION_RELATIVE == display->mPosition, "Unexpected type of positioning"); for (nsIFrame *cont = aFrame; cont; cont = nsLayoutUtils::GetNextContinuationOrSpecialSibling(cont)) { nsIFrame* cb = cont->GetContainingBlock(); nsMargin newOffsets; const nsSize size = cb->GetContentRectRelativeToSelf().Size(); nsHTMLReflowState::ComputeRelativeOffsets( cb->StyleVisibility()->mDirection, cont, size.width, size.height, newOffsets); NS_ASSERTION(newOffsets.left == -newOffsets.right && newOffsets.top == -newOffsets.bottom, "ComputeRelativeOffsets should return valid results"); // nsHTMLReflowState::ApplyRelativePositioning would work here, but // since we've already checked mPosition and aren't changing the frame's // normal position, go ahead and add the offsets directly. cont->SetPosition(cont->GetNormalPosition() + nsPoint(newOffsets.left, newOffsets.top)); } } return true; } // For absolute positioning, the width can potentially change if width is // auto and either of left or right are not. The height can also potentially // change if height is auto and either of top or bottom are not. In these // cases we fall back to a reflow, and in all other cases, we attempt to // move the frame here. // Note that it is possible for the dimensions to not change in the above // cases, so we should be a little smarter here and only fall back to reflow // when the dimensions will really change (bug 745485). const nsStylePosition* position = aFrame->StylePosition(); if (position->mWidth.GetUnit() != eStyleUnit_Auto && position->mHeight.GetUnit() != eStyleUnit_Auto) { // For the absolute positioning case, set up a fake HTML reflow state for // the frame, and then get the offsets from it. nsRefPtr rc = aFrame->PresContext()->GetPresShell()-> GetReferenceRenderingContext(); // Construct a bogus parent reflow state so that there's a usable // containing block reflow state. nsIFrame* parentFrame = aFrame->GetParent(); nsSize parentSize = parentFrame->GetSize(); nsFrameState savedState = parentFrame->GetStateBits(); nsHTMLReflowState parentReflowState(aFrame->PresContext(), parentFrame, rc, parentSize); parentFrame->RemoveStateBits(~nsFrameState(0)); parentFrame->AddStateBits(savedState); NS_WARN_IF_FALSE(parentSize.width != NS_INTRINSICSIZE && parentSize.height != NS_INTRINSICSIZE, "parentSize should be valid"); parentReflowState.SetComputedWidth(std::max(parentSize.width, 0)); parentReflowState.SetComputedHeight(std::max(parentSize.height, 0)); parentReflowState.mComputedMargin.SizeTo(0, 0, 0, 0); parentSize.height = NS_AUTOHEIGHT; parentReflowState.mComputedPadding = parentFrame->GetUsedPadding(); parentReflowState.mComputedBorderPadding = parentFrame->GetUsedBorderAndPadding(); nsSize availSize(parentSize.width, NS_INTRINSICSIZE); nsSize size = aFrame->GetSize(); ViewportFrame* viewport = do_QueryFrame(parentFrame); nsSize cbSize = viewport ? viewport->AdjustReflowStateAsContainingBlock(&parentReflowState).Size() : aFrame->GetContainingBlock()->GetSize(); const nsMargin& parentBorder = parentReflowState.mStyleBorder->GetComputedBorder(); cbSize -= nsSize(parentBorder.LeftRight(), parentBorder.TopBottom()); nsHTMLReflowState reflowState(aFrame->PresContext(), parentReflowState, aFrame, availSize, cbSize.width, cbSize.height); // If we're solving for 'left' or 'top', then compute it here, in order to // match the reflow code path. if (NS_AUTOOFFSET == reflowState.mComputedOffsets.left) { reflowState.mComputedOffsets.left = cbSize.width - reflowState.mComputedOffsets.right - reflowState.mComputedMargin.right - size.width - reflowState.mComputedMargin.left; } if (NS_AUTOOFFSET == reflowState.mComputedOffsets.top) { reflowState.mComputedOffsets.top = cbSize.height - reflowState.mComputedOffsets.bottom - reflowState.mComputedMargin.bottom - size.height - reflowState.mComputedMargin.top; } // Move the frame nsPoint pos(parentBorder.left + reflowState.mComputedOffsets.left + reflowState.mComputedMargin.left, parentBorder.top + reflowState.mComputedOffsets.top + reflowState.mComputedMargin.top); aFrame->SetPosition(pos); return true; } // Fall back to a reflow StyleChangeReflow(aFrame, nsChangeHint_NeedReflow); return false; } nsresult RestyleManager::StyleChangeReflow(nsIFrame* aFrame, nsChangeHint aHint) { // If the frame hasn't even received an initial reflow, then don't // send it a style-change reflow! if (aFrame->GetStateBits() & NS_FRAME_FIRST_REFLOW) return NS_OK; nsIPresShell::IntrinsicDirty dirtyType; if (aHint & nsChangeHint_ClearDescendantIntrinsics) { NS_ASSERTION(aHint & nsChangeHint_ClearAncestorIntrinsics, "Please read the comments in nsChangeHint.h"); dirtyType = nsIPresShell::eStyleChange; } else if (aHint & nsChangeHint_ClearAncestorIntrinsics) { dirtyType = nsIPresShell::eTreeChange; } else { dirtyType = nsIPresShell::eResize; } nsFrameState dirtyBits; if (aHint & nsChangeHint_NeedDirtyReflow) { dirtyBits = NS_FRAME_IS_DIRTY; } else { dirtyBits = NS_FRAME_HAS_DIRTY_CHILDREN; } do { mPresContext->PresShell()->FrameNeedsReflow(aFrame, dirtyType, dirtyBits); aFrame = nsLayoutUtils::GetNextContinuationOrSpecialSibling(aFrame); } while (aFrame); return NS_OK; } NS_DECLARE_FRAME_PROPERTY(ChangeListProperty, nullptr) /** * Return true if aFrame's subtree has placeholders for out-of-flow content * whose 'position' style's bit in aPositionMask is set. */ static bool FrameHasPositionedPlaceholderDescendants(nsIFrame* aFrame, uint32_t aPositionMask) { const nsIFrame::ChildListIDs skip(nsIFrame::kAbsoluteList | nsIFrame::kFixedList); for (nsIFrame::ChildListIterator lists(aFrame); !lists.IsDone(); lists.Next()) { if (!skip.Contains(lists.CurrentID())) { for (nsFrameList::Enumerator childFrames(lists.CurrentList()); !childFrames.AtEnd(); childFrames.Next()) { nsIFrame* f = childFrames.get(); if (f->GetType() == nsGkAtoms::placeholderFrame) { nsIFrame* outOfFlow = nsPlaceholderFrame::GetRealFrameForPlaceholder(f); // If SVG text frames could appear here, they could confuse us since // they ignore their position style ... but they can't. NS_ASSERTION(!outOfFlow->IsSVGText(), "SVG text frames can't be out of flow"); if (aPositionMask & (1 << outOfFlow->StyleDisplay()->mPosition)) { return true; } } if (FrameHasPositionedPlaceholderDescendants(f, aPositionMask)) { return true; } } } } return false; } static bool NeedToReframeForAddingOrRemovingTransform(nsIFrame* aFrame) { static_assert(0 <= NS_STYLE_POSITION_ABSOLUTE && NS_STYLE_POSITION_ABSOLUTE < 32, "Style constant out of range"); static_assert(0 <= NS_STYLE_POSITION_FIXED && NS_STYLE_POSITION_FIXED < 32, "Style constant out of range"); uint32_t positionMask; // Don't call aFrame->IsPositioned here, since that returns true if // the frame already has a transform, and we want to ignore that here if (aFrame->IsAbsolutelyPositioned() || aFrame->IsRelativelyPositioned()) { // This frame is a container for abs-pos descendants whether or not it // has a transform. // So abs-pos descendants are no problem; we only need to reframe if // we have fixed-pos descendants. positionMask = 1 << NS_STYLE_POSITION_FIXED; } else { // This frame may not be a container for abs-pos descendants already. // So reframe if we have abs-pos or fixed-pos descendants. positionMask = (1 << NS_STYLE_POSITION_FIXED) | (1 << NS_STYLE_POSITION_ABSOLUTE); } for (nsIFrame* f = aFrame; f; f = nsLayoutUtils::GetNextContinuationOrSpecialSibling(f)) { if (FrameHasPositionedPlaceholderDescendants(f, positionMask)) { return true; } } return false; } nsresult RestyleManager::ProcessRestyledFrames(nsStyleChangeList& aChangeList) { NS_ASSERTION(!nsContentUtils::IsSafeToRunScript(), "Someone forgot a script blocker"); int32_t count = aChangeList.Count(); if (!count) return NS_OK; PROFILER_LABEL("CSS", "ProcessRestyledFrames"); // Make sure to not rebuild quote or counter lists while we're // processing restyles FrameConstructor()->BeginUpdate(); FramePropertyTable* propTable = mPresContext->PropertyTable(); // Mark frames so that we skip frames that die along the way, bug 123049. // A frame can be in the list multiple times with different hints. Further // optmization is possible if nsStyleChangeList::AppendChange could coalesce int32_t index = count; while (0 <= --index) { const nsStyleChangeData* changeData; aChangeList.ChangeAt(index, &changeData); if (changeData->mFrame) { propTable->Set(changeData->mFrame, ChangeListProperty(), NS_INT32_TO_PTR(1)); } } index = count; bool didUpdateCursor = false; while (0 <= --index) { nsIFrame* frame; nsIContent* content; bool didReflowThisFrame = false; nsChangeHint hint; aChangeList.ChangeAt(index, frame, content, hint); NS_ASSERTION(!(hint & nsChangeHint_AllReflowHints) || (hint & nsChangeHint_NeedReflow), "Reflow hint bits set without actually asking for a reflow"); // skip any frame that has been destroyed due to a ripple effect if (frame && !propTable->Get(frame, ChangeListProperty())) { continue; } if (frame && frame->GetContent() != content) { // XXXbz this is due to image maps messing with the primary frame of // s. See bug 135040. Remove this block once that's fixed. frame = nullptr; if (!(hint & nsChangeHint_ReconstructFrame)) { continue; } } if ((hint & nsChangeHint_AddOrRemoveTransform) && frame && !(hint & nsChangeHint_ReconstructFrame)) { if (NeedToReframeForAddingOrRemovingTransform(frame)) { NS_UpdateHint(hint, nsChangeHint_ReconstructFrame); } else { for (nsIFrame *cont = frame; cont; cont = nsLayoutUtils::GetNextContinuationOrSpecialSibling(cont)) { // Normally frame construction would set state bits as needed, // but we're not going to reconstruct the frame so we need to set them. // It's because we need to set this state on each affected frame // that we can't coalesce nsChangeHint_AddOrRemoveTransform hints up // to ancestors (i.e. it can't be an inherited change hint). if (cont->IsPositioned()) { // If a transform has been added, we'll be taking this path, // but we may be taking this path even if a transform has been // removed. It's OK to add the bit even if it's not needed. cont->AddStateBits(NS_FRAME_MAY_BE_TRANSFORMED); if (!cont->IsAbsoluteContainer() && (cont->GetStateBits() & NS_FRAME_CAN_HAVE_ABSPOS_CHILDREN)) { cont->MarkAsAbsoluteContainingBlock(); } } else { // Don't remove NS_FRAME_MAY_BE_TRANSFORMED since it may still by // transformed by other means. It's OK to have the bit even if it's // not needed. if (cont->IsAbsoluteContainer()) { cont->MarkAsNotAbsoluteContainingBlock(); } } } } } if (hint & nsChangeHint_ReconstructFrame) { // If we ever start passing true here, be careful of restyles // that involve a reframe and animations. In particular, if the // restyle we're processing here is an animation restyle, but // the style resolution we will do for the frame construction // happens async when we're not in an animation restyle already, // problems could arise. FrameConstructor()->RecreateFramesForContent(content, false); } else { NS_ASSERTION(frame, "This shouldn't happen"); if ((frame->GetStateBits() & NS_FRAME_SVG_LAYOUT) && (frame->GetStateBits() & NS_FRAME_IS_NONDISPLAY)) { // frame does not maintain overflow rects, so avoid calling // FinishAndStoreOverflow on it: hint = NS_SubtractHint(hint, NS_CombineHint(nsChangeHint_UpdateOverflow, nsChangeHint_ChildrenOnlyTransform)); } if (hint & nsChangeHint_UpdateEffects) { for (nsIFrame *cont = frame; cont; cont = nsLayoutUtils::GetNextContinuationOrSpecialSibling(cont)) { nsSVGEffects::UpdateEffects(cont); } } if (hint & nsChangeHint_NeedReflow) { StyleChangeReflow(frame, hint); didReflowThisFrame = true; } if (hint & (nsChangeHint_RepaintFrame | nsChangeHint_SyncFrameView | nsChangeHint_UpdateOpacityLayer | nsChangeHint_UpdateTransformLayer | nsChangeHint_ChildrenOnlyTransform)) { ApplyRenderingChangeToTree(mPresContext, frame, hint); } if ((hint & nsChangeHint_RecomputePosition) && !didReflowThisFrame) { // It is possible for this to fall back to a reflow if (!RecomputePosition(frame)) { didReflowThisFrame = true; } } NS_ASSERTION(!(hint & nsChangeHint_ChildrenOnlyTransform) || (hint & nsChangeHint_UpdateOverflow), "nsChangeHint_UpdateOverflow should be passed too"); if ((hint & nsChangeHint_UpdateOverflow) && !didReflowThisFrame) { if (hint & nsChangeHint_ChildrenOnlyTransform) { // The overflow areas of the child frames need to be updated: nsIFrame* hintFrame = GetFrameForChildrenOnlyTransformHint(frame); nsIFrame* childFrame = hintFrame->GetFirstPrincipalChild(); NS_ASSERTION(!nsLayoutUtils::GetNextContinuationOrSpecialSibling(frame), "SVG frames should not have continuations or special siblings"); NS_ASSERTION(!nsLayoutUtils::GetNextContinuationOrSpecialSibling(hintFrame), "SVG frames should not have continuations or special siblings"); for ( ; childFrame; childFrame = childFrame->GetNextSibling()) { NS_ABORT_IF_FALSE(childFrame->IsFrameOfType(nsIFrame::eSVG), "Not expecting non-SVG children"); // If |childFrame| is dirty or has dirty children, we don't bother // updating overflows since that will happen when it's reflowed. if (!(childFrame->GetStateBits() & (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN))) { mOverflowChangedTracker.AddFrame(childFrame); } NS_ASSERTION(!nsLayoutUtils::GetNextContinuationOrSpecialSibling(childFrame), "SVG frames should not have continuations or special siblings"); NS_ASSERTION(childFrame->GetParent() == hintFrame, "SVG child frame not expected to have different parent"); } } // If |frame| is dirty or has dirty children, we don't bother updating // overflows since that will happen when it's reflowed. if (!(frame->GetStateBits() & (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN))) { for (nsIFrame *cont = frame; cont; cont = nsLayoutUtils::GetNextContinuationOrSpecialSibling(cont)) { mOverflowChangedTracker.AddFrame(cont); } } } if ((hint & nsChangeHint_UpdateCursor) && !didUpdateCursor) { mPresContext->PresShell()->SynthesizeMouseMove(false); didUpdateCursor = true; } } } FrameConstructor()->EndUpdate(); // cleanup references and verify the style tree. Note that the latter needs // to happen once we've processed the whole list, since until then the tree // is not in fact in a consistent state. index = count; while (0 <= --index) { const nsStyleChangeData* changeData; aChangeList.ChangeAt(index, &changeData); if (changeData->mFrame) { propTable->Delete(changeData->mFrame, ChangeListProperty()); } #ifdef DEBUG // reget frame from content since it may have been regenerated... if (changeData->mContent) { if (!nsAnimationManager::ContentOrAncestorHasAnimation(changeData->mContent) && !nsTransitionManager::ContentOrAncestorHasTransition(changeData->mContent)) { nsIFrame* frame = changeData->mContent->GetPrimaryFrame(); if (frame) { DebugVerifyStyleTree(frame); } } } else if (!changeData->mFrame || changeData->mFrame->GetType() != nsGkAtoms::viewportFrame) { NS_WARNING("Unable to test style tree integrity -- no content node " "(and not a viewport frame)"); } #endif } aChangeList.Clear(); return NS_OK; } void RestyleManager::RestyleElement(Element* aElement, nsIFrame* aPrimaryFrame, nsChangeHint aMinHint, RestyleTracker& aRestyleTracker, bool aRestyleDescendants) { NS_ASSERTION(aPrimaryFrame == aElement->GetPrimaryFrame(), "frame/content mismatch"); if (aPrimaryFrame && aPrimaryFrame->GetContent() != aElement) { // XXXbz this is due to image maps messing with the primary frame pointer // of s. See bug 135040. We can remove this block once that's fixed. aPrimaryFrame = nullptr; } NS_ASSERTION(!aPrimaryFrame || aPrimaryFrame->GetContent() == aElement, "frame/content mismatch"); // If we're restyling the root element and there are 'rem' units in // use, handle dynamic changes to the definition of a 'rem' here. if (mPresContext->UsesRootEMUnits() && aPrimaryFrame) { nsStyleContext *oldContext = aPrimaryFrame->StyleContext(); if (!oldContext->GetParent()) { // check that we're the root element nsRefPtr newContext = mPresContext->StyleSet()-> ResolveStyleFor(aElement, nullptr /* == oldContext->GetParent() */); if (oldContext->StyleFont()->mFont.size != newContext->StyleFont()->mFont.size) { // The basis for 'rem' units has changed. newContext = nullptr; DoRebuildAllStyleData(aRestyleTracker, nsChangeHint(0)); if (aMinHint == 0) { return; } aPrimaryFrame = aElement->GetPrimaryFrame(); } } } if (aMinHint & nsChangeHint_ReconstructFrame) { FrameConstructor()->RecreateFramesForContent(aElement, false); } else if (aPrimaryFrame) { nsStyleChangeList changeList; ComputeStyleChangeFor(aPrimaryFrame, &changeList, aMinHint, aRestyleTracker, aRestyleDescendants); ProcessRestyledFrames(changeList); } else { // no frames, reconstruct for content FrameConstructor()->MaybeRecreateFramesForElement(aElement); } } // Forwarded nsIDocumentObserver method, to handle restyling (and // passing the notification to the frame). nsresult RestyleManager::ContentStateChanged(nsIContent* aContent, nsEventStates aStateMask) { // XXXbz it would be good if this function only took Elements, but // we'd have to make ESM guarantee that usefully. if (!aContent->IsElement()) { return NS_OK; } Element* aElement = aContent->AsElement(); nsStyleSet* styleSet = mPresContext->StyleSet(); NS_ASSERTION(styleSet, "couldn't get style set"); nsChangeHint hint = NS_STYLE_HINT_NONE; // Any change to a content state that affects which frames we construct // must lead to a frame reconstruct here if we already have a frame. // Note that we never decide through non-CSS means to not create frames // based on content states, so if we already don't have a frame we don't // need to force a reframe -- if it's needed, the HasStateDependentStyle // call will handle things. nsIFrame* primaryFrame = aElement->GetPrimaryFrame(); if (primaryFrame) { // If it's generated content, ignore LOADING/etc state changes on it. if (!primaryFrame->IsGeneratedContentFrame() && aStateMask.HasAtLeastOneOfStates(NS_EVENT_STATE_BROKEN | NS_EVENT_STATE_USERDISABLED | NS_EVENT_STATE_SUPPRESSED | NS_EVENT_STATE_LOADING)) { hint = nsChangeHint_ReconstructFrame; } else { uint8_t app = primaryFrame->StyleDisplay()->mAppearance; if (app) { nsITheme *theme = mPresContext->GetTheme(); if (theme && theme->ThemeSupportsWidget(mPresContext, primaryFrame, app)) { bool repaint = false; theme->WidgetStateChanged(primaryFrame, app, nullptr, &repaint); if (repaint) { NS_UpdateHint(hint, nsChangeHint_RepaintFrame); } } } } primaryFrame->ContentStatesChanged(aStateMask); } nsRestyleHint rshint = styleSet->HasStateDependentStyle(mPresContext, aElement, aStateMask); if (aStateMask.HasState(NS_EVENT_STATE_HOVER) && rshint != 0) { ++mHoverGeneration; } if (aStateMask.HasState(NS_EVENT_STATE_VISITED)) { // Exposing information to the page about whether the link is // visited or not isn't really something we can worry about here. // FIXME: We could probably do this a bit better. NS_UpdateHint(hint, nsChangeHint_RepaintFrame); } PostRestyleEvent(aElement, rshint, hint); return NS_OK; } // Forwarded nsIMutationObserver method, to handle restyling. void RestyleManager::AttributeWillChange(Element* aElement, int32_t aNameSpaceID, nsIAtom* aAttribute, int32_t aModType) { nsRestyleHint rshint = mPresContext->StyleSet()->HasAttributeDependentStyle(mPresContext, aElement, aAttribute, aModType, false); PostRestyleEvent(aElement, rshint, NS_STYLE_HINT_NONE); } // Forwarded nsIMutationObserver method, to handle restyling (and // passing the notification to the frame). void RestyleManager::AttributeChanged(Element* aElement, int32_t aNameSpaceID, nsIAtom* aAttribute, int32_t aModType) { // Hold onto the PresShell to prevent ourselves from being destroyed. // XXXbz how, exactly, would this attribute change cause us to be // destroyed from inside this function? nsCOMPtr shell = mPresContext->GetPresShell(); // Get the frame associated with the content which is the highest in the frame tree nsIFrame* primaryFrame = aElement->GetPrimaryFrame(); #if 0 NS_FRAME_LOG(NS_FRAME_TRACE_CALLS, ("RestyleManager::AttributeChanged: content=%p[%s] frame=%p", aContent, ContentTag(aElement, 0), frame)); #endif // the style tag has its own interpretation based on aHint nsChangeHint hint = aElement->GetAttributeChangeHint(aAttribute, aModType); bool reframe = (hint & nsChangeHint_ReconstructFrame) != 0; #ifdef MOZ_XUL // The following listbox widget trap prevents offscreen listbox widget // content from being removed and re-inserted (which is what would // happen otherwise). if (!primaryFrame && !reframe) { int32_t namespaceID; nsIAtom* tag = mPresContext->Document()->BindingManager()-> ResolveTag(aElement, &namespaceID); if (namespaceID == kNameSpaceID_XUL && (tag == nsGkAtoms::listitem || tag == nsGkAtoms::listcell)) return; } if (aAttribute == nsGkAtoms::tooltiptext || aAttribute == nsGkAtoms::tooltip) { nsIRootBox* rootBox = nsIRootBox::GetRootBox(mPresContext->GetPresShell()); if (rootBox) { if (aModType == nsIDOMMutationEvent::REMOVAL) rootBox->RemoveTooltipSupport(aElement); if (aModType == nsIDOMMutationEvent::ADDITION) rootBox->AddTooltipSupport(aElement); } } #endif // MOZ_XUL if (primaryFrame) { // See if we have appearance information for a theme. const nsStyleDisplay* disp = primaryFrame->StyleDisplay(); if (disp->mAppearance) { nsITheme *theme = mPresContext->GetTheme(); if (theme && theme->ThemeSupportsWidget(mPresContext, primaryFrame, disp->mAppearance)) { bool repaint = false; theme->WidgetStateChanged(primaryFrame, disp->mAppearance, aAttribute, &repaint); if (repaint) NS_UpdateHint(hint, nsChangeHint_RepaintFrame); } } // let the frame deal with it now, so we don't have to deal later primaryFrame->AttributeChanged(aNameSpaceID, aAttribute, aModType); // XXXwaterson should probably check for special IB siblings // here, and propagate the AttributeChanged notification to // them, as well. Currently, inline frames don't do anything on // this notification, so it's not that big a deal. } // See if we can optimize away the style re-resolution -- must be called after // the frame's AttributeChanged() in case it does something that affects the style nsRestyleHint rshint = mPresContext->StyleSet()->HasAttributeDependentStyle(mPresContext, aElement, aAttribute, aModType, true); PostRestyleEvent(aElement, rshint, hint); } void RestyleManager::RestyleForEmptyChange(Element* aContainer) { // In some cases (:empty + E, :empty ~ E), a change if the content of // an element requires restyling its parent's siblings. nsRestyleHint hint = eRestyle_Subtree; nsIContent* grandparent = aContainer->GetParent(); if (grandparent && (grandparent->GetFlags() & NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS)) { hint = nsRestyleHint(hint | eRestyle_LaterSiblings); } PostRestyleEvent(aContainer, hint, NS_STYLE_HINT_NONE); } void RestyleManager::RestyleForAppend(Element* aContainer, nsIContent* aFirstNewContent) { NS_ASSERTION(aContainer, "must have container for append"); #ifdef DEBUG { for (nsIContent* cur = aFirstNewContent; cur; cur = cur->GetNextSibling()) { NS_ASSERTION(!cur->IsRootOfAnonymousSubtree(), "anonymous nodes should not be in child lists"); } } #endif uint32_t selectorFlags = aContainer->GetFlags() & (NODE_ALL_SELECTOR_FLAGS & ~NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS); if (selectorFlags == 0) return; if (selectorFlags & NODE_HAS_EMPTY_SELECTOR) { // see whether we need to restyle the container bool wasEmpty = true; // :empty or :-moz-only-whitespace for (nsIContent* cur = aContainer->GetFirstChild(); cur != aFirstNewContent; cur = cur->GetNextSibling()) { // We don't know whether we're testing :empty or :-moz-only-whitespace, // so be conservative and assume :-moz-only-whitespace (i.e., make // IsSignificantChild less likely to be true, and thus make us more // likely to restyle). if (nsStyleUtil::IsSignificantChild(cur, true, false)) { wasEmpty = false; break; } } if (wasEmpty) { RestyleForEmptyChange(aContainer); return; } } if (selectorFlags & NODE_HAS_SLOW_SELECTOR) { PostRestyleEvent(aContainer, eRestyle_Subtree, NS_STYLE_HINT_NONE); // Restyling the container is the most we can do here, so we're done. return; } if (selectorFlags & NODE_HAS_EDGE_CHILD_SELECTOR) { // restyle the last element child before this node for (nsIContent* cur = aFirstNewContent->GetPreviousSibling(); cur; cur = cur->GetPreviousSibling()) { if (cur->IsElement()) { PostRestyleEvent(cur->AsElement(), eRestyle_Subtree, NS_STYLE_HINT_NONE); break; } } } } // Needed since we can't use PostRestyleEvent on non-elements (with // eRestyle_LaterSiblings or nsRestyleHint(eRestyle_Subtree | // eRestyle_LaterSiblings) as appropriate). static void RestyleSiblingsStartingWith(RestyleManager* aRestyleManager, nsIContent* aStartingSibling /* may be null */) { for (nsIContent *sibling = aStartingSibling; sibling; sibling = sibling->GetNextSibling()) { if (sibling->IsElement()) { aRestyleManager-> PostRestyleEvent(sibling->AsElement(), nsRestyleHint(eRestyle_Subtree | eRestyle_LaterSiblings), NS_STYLE_HINT_NONE); break; } } } // Restyling for a ContentInserted or CharacterDataChanged notification. // This could be used for ContentRemoved as well if we got the // notification before the removal happened (and sometimes // CharacterDataChanged is more like a removal than an addition). // The comments are written and variables are named in terms of it being // a ContentInserted notification. void RestyleManager::RestyleForInsertOrChange(Element* aContainer, nsIContent* aChild) { NS_ASSERTION(!aChild->IsRootOfAnonymousSubtree(), "anonymous nodes should not be in child lists"); uint32_t selectorFlags = aContainer ? (aContainer->GetFlags() & NODE_ALL_SELECTOR_FLAGS) : 0; if (selectorFlags == 0) return; if (selectorFlags & NODE_HAS_EMPTY_SELECTOR) { // see whether we need to restyle the container bool wasEmpty = true; // :empty or :-moz-only-whitespace for (nsIContent* child = aContainer->GetFirstChild(); child; child = child->GetNextSibling()) { if (child == aChild) continue; // We don't know whether we're testing :empty or :-moz-only-whitespace, // so be conservative and assume :-moz-only-whitespace (i.e., make // IsSignificantChild less likely to be true, and thus make us more // likely to restyle). if (nsStyleUtil::IsSignificantChild(child, true, false)) { wasEmpty = false; break; } } if (wasEmpty) { RestyleForEmptyChange(aContainer); return; } } if (selectorFlags & NODE_HAS_SLOW_SELECTOR) { PostRestyleEvent(aContainer, eRestyle_Subtree, NS_STYLE_HINT_NONE); // Restyling the container is the most we can do here, so we're done. return; } if (selectorFlags & NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS) { // Restyle all later siblings. RestyleSiblingsStartingWith(this, aChild->GetNextSibling()); } if (selectorFlags & NODE_HAS_EDGE_CHILD_SELECTOR) { // restyle the previously-first element child if it is after this node bool passedChild = false; for (nsIContent* content = aContainer->GetFirstChild(); content; content = content->GetNextSibling()) { if (content == aChild) { passedChild = true; continue; } if (content->IsElement()) { if (passedChild) { PostRestyleEvent(content->AsElement(), eRestyle_Subtree, NS_STYLE_HINT_NONE); } break; } } // restyle the previously-last element child if it is before this node passedChild = false; for (nsIContent* content = aContainer->GetLastChild(); content; content = content->GetPreviousSibling()) { if (content == aChild) { passedChild = true; continue; } if (content->IsElement()) { if (passedChild) { PostRestyleEvent(content->AsElement(), eRestyle_Subtree, NS_STYLE_HINT_NONE); } break; } } } } void RestyleManager::RestyleForRemove(Element* aContainer, nsIContent* aOldChild, nsIContent* aFollowingSibling) { if (aOldChild->IsRootOfAnonymousSubtree()) { // This should be an assert, but this is called incorrectly in // nsHTMLEditor::DeleteRefToAnonymousNode and the assertions were clogging // up the logs. Make it an assert again when that's fixed. NS_WARNING("anonymous nodes should not be in child lists (bug 439258)"); } uint32_t selectorFlags = aContainer ? (aContainer->GetFlags() & NODE_ALL_SELECTOR_FLAGS) : 0; if (selectorFlags == 0) return; if (selectorFlags & NODE_HAS_EMPTY_SELECTOR) { // see whether we need to restyle the container bool isEmpty = true; // :empty or :-moz-only-whitespace for (nsIContent* child = aContainer->GetFirstChild(); child; child = child->GetNextSibling()) { // We don't know whether we're testing :empty or :-moz-only-whitespace, // so be conservative and assume :-moz-only-whitespace (i.e., make // IsSignificantChild less likely to be true, and thus make us more // likely to restyle). if (nsStyleUtil::IsSignificantChild(child, true, false)) { isEmpty = false; break; } } if (isEmpty) { RestyleForEmptyChange(aContainer); return; } } if (selectorFlags & NODE_HAS_SLOW_SELECTOR) { PostRestyleEvent(aContainer, eRestyle_Subtree, NS_STYLE_HINT_NONE); // Restyling the container is the most we can do here, so we're done. return; } if (selectorFlags & NODE_HAS_SLOW_SELECTOR_LATER_SIBLINGS) { // Restyle all later siblings. RestyleSiblingsStartingWith(this, aFollowingSibling); } if (selectorFlags & NODE_HAS_EDGE_CHILD_SELECTOR) { // restyle the now-first element child if it was after aOldChild bool reachedFollowingSibling = false; for (nsIContent* content = aContainer->GetFirstChild(); content; content = content->GetNextSibling()) { if (content == aFollowingSibling) { reachedFollowingSibling = true; // do NOT continue here; we might want to restyle this node } if (content->IsElement()) { if (reachedFollowingSibling) { PostRestyleEvent(content->AsElement(), eRestyle_Subtree, NS_STYLE_HINT_NONE); } break; } } // restyle the now-last element child if it was before aOldChild reachedFollowingSibling = (aFollowingSibling == nullptr); for (nsIContent* content = aContainer->GetLastChild(); content; content = content->GetPreviousSibling()) { if (content->IsElement()) { if (reachedFollowingSibling) { PostRestyleEvent(content->AsElement(), eRestyle_Subtree, NS_STYLE_HINT_NONE); } break; } if (content == aFollowingSibling) { reachedFollowingSibling = true; } } } } void RestyleManager::RebuildAllStyleData(nsChangeHint aExtraHint) { NS_ASSERTION(!(aExtraHint & nsChangeHint_ReconstructFrame), "Should not reconstruct the root of the frame tree. " "Use ReconstructDocElementHierarchy instead."); mRebuildAllStyleData = false; NS_UpdateHint(aExtraHint, mRebuildAllExtraHint); mRebuildAllExtraHint = nsChangeHint(0); nsIPresShell* presShell = mPresContext->GetPresShell(); if (!presShell || !presShell->GetRootFrame()) return; // Make sure that the viewmanager will outlive the presshell nsRefPtr vm = presShell->GetViewManager(); // Processing the style changes could cause a flush that propagates to // the parent frame and thus destroys the pres shell. nsCOMPtr kungFuDeathGrip(presShell); // We may reconstruct frames below and hence process anything that is in the // tree. We don't want to get notified to process those items again after. presShell->GetDocument()->FlushPendingNotifications(Flush_ContentAndNotify); nsAutoScriptBlocker scriptBlocker; mPresContext->SetProcessingRestyles(true); DoRebuildAllStyleData(mPendingRestyles, aExtraHint); mPresContext->SetProcessingRestyles(false); // Make sure that we process any pending animation restyles from the // above style change. Note that we can *almost* implement the above // by just posting a style change -- except we really need to restyle // the root frame rather than the root element's primary frame. ProcessPendingRestyles(); } void RestyleManager::DoRebuildAllStyleData(RestyleTracker& aRestyleTracker, nsChangeHint aExtraHint) { // Tell the style set to get the old rule tree out of the way // so we can recalculate while maintaining rule tree immutability nsresult rv = mPresContext->StyleSet()->BeginReconstruct(); if (NS_FAILED(rv)) { return; } // Recalculate all of the style contexts for the document // Note that we can ignore the return value of ComputeStyleChangeFor // because we never need to reframe the root frame // XXX This could be made faster by not rerunning rule matching // (but note that nsPresShell::SetPreferenceStyleRules currently depends // on us re-running rule matching here nsStyleChangeList changeList; // XXX Does it matter that we're passing aExtraHint to the real root // frame and not the root node's primary frame? // Note: The restyle tracker we pass in here doesn't matter. ComputeStyleChangeFor(mPresContext->PresShell()->GetRootFrame(), &changeList, aExtraHint, aRestyleTracker, true); // Process the required changes ProcessRestyledFrames(changeList); FlushOverflowChangedTracker(); // Tell the style set it's safe to destroy the old rule tree. We // must do this after the ProcessRestyledFrames call in case the // change list has frame reconstructs in it (since frames to be // reconstructed will still have their old style context pointers // until they are destroyed). mPresContext->StyleSet()->EndReconstruct(); } void RestyleManager::ProcessPendingRestyles() { NS_PRECONDITION(mPresContext->Document(), "No document? Pshaw!"); NS_PRECONDITION(!nsContentUtils::IsSafeToRunScript(), "Missing a script blocker!"); // Process non-animation restyles... NS_ABORT_IF_FALSE(!mPresContext->IsProcessingRestyles(), "Nesting calls to ProcessPendingRestyles?"); mPresContext->SetProcessingRestyles(true); // Before we process any restyles, we need to ensure that style // resulting from any throttled animations (animations that we're // running entirely on the compositor thread) is up-to-date, so that // if any style changes we cause trigger transitions, we have the // correct old style for starting the transition. if (nsLayoutUtils::AreAsyncAnimationsEnabled() && mPendingRestyles.Count() > 0) { ++mAnimationGeneration; mPresContext->TransitionManager()->UpdateAllThrottledStyles(); } mPendingRestyles.ProcessRestyles(); #ifdef DEBUG uint32_t oldPendingRestyleCount = mPendingRestyles.Count(); #endif // ...and then process animation restyles. This needs to happen // second because we need to start animations that resulted from the // first set of restyles (e.g., CSS transitions with negative // transition-delay), and because we need to immediately // restyle-with-animation any just-restyled elements that are // mid-transition (since processing the non-animation restyle ignores // the running transition so it can check for a new change on the same // property, and then posts an immediate animation style change). mPresContext->SetProcessingAnimationStyleChange(true); mPendingAnimationRestyles.ProcessRestyles(); mPresContext->SetProcessingAnimationStyleChange(false); mPresContext->SetProcessingRestyles(false); NS_POSTCONDITION(mPendingRestyles.Count() == oldPendingRestyleCount, "We should not have posted new non-animation restyles while " "processing animation restyles"); if (mRebuildAllStyleData) { // We probably wasted a lot of work up above, but this seems safest // and it should be rarely used. // This might add us as a refresh observer again; that's ok. RebuildAllStyleData(nsChangeHint(0)); } } void RestyleManager::BeginProcessingRestyles() { // Make sure to not rebuild quote or counter lists while we're // processing restyles mPresContext->FrameConstructor()->BeginUpdate(); mInStyleRefresh = true; } void RestyleManager::EndProcessingRestyles() { FlushOverflowChangedTracker(); // Set mInStyleRefresh to false now, since the EndUpdate call might // add more restyles. mInStyleRefresh = false; mPresContext->FrameConstructor()->EndUpdate(); #ifdef DEBUG mPresContext->PresShell()->VerifyStyleTree(); #endif } void RestyleManager::PostRestyleEventCommon(Element* aElement, nsRestyleHint aRestyleHint, nsChangeHint aMinChangeHint, bool aForAnimation) { if (MOZ_UNLIKELY(mPresContext->PresShell()->IsDestroying())) { return; } if (aRestyleHint == 0 && !aMinChangeHint) { // Nothing to do here return; } RestyleTracker& tracker = aForAnimation ? mPendingAnimationRestyles : mPendingRestyles; tracker.AddPendingRestyle(aElement, aRestyleHint, aMinChangeHint); PostRestyleEventInternal(false); } void RestyleManager::PostRestyleEventInternal(bool aForLazyConstruction) { // Make sure we're not in a style refresh; if we are, we still have // a call to ProcessPendingRestyles coming and there's no need to // add ourselves as a refresh observer until then. bool inRefresh = !aForLazyConstruction && mInStyleRefresh; nsIPresShell* presShell = mPresContext->PresShell(); if (!mObservingRefreshDriver && !inRefresh) { mObservingRefreshDriver = mPresContext->RefreshDriver()-> AddStyleFlushObserver(presShell); } // Unconditionally flag our document as needing a flush. The other // option here would be a dedicated boolean to track whether we need // to do so (set here and unset in ProcessPendingRestyles). presShell->GetDocument()->SetNeedStyleFlush(); } void RestyleManager::PostRebuildAllStyleDataEvent(nsChangeHint aExtraHint) { NS_ASSERTION(!(aExtraHint & nsChangeHint_ReconstructFrame), "Should not reconstruct the root of the frame tree. " "Use ReconstructDocElementHierarchy instead."); mRebuildAllStyleData = true; NS_UpdateHint(mRebuildAllExtraHint, aExtraHint); // Get a restyle event posted if necessary PostRestyleEventInternal(false); } #ifdef DEBUG static void DumpContext(nsIFrame* aFrame, nsStyleContext* aContext) { if (aFrame) { fputs("frame: ", stdout); nsAutoString name; aFrame->GetFrameName(name); fputs(NS_LossyConvertUTF16toASCII(name).get(), stdout); fprintf(stdout, " (%p)", static_cast(aFrame)); } if (aContext) { fprintf(stdout, " style: %p ", static_cast(aContext)); nsIAtom* pseudoTag = aContext->GetPseudo(); if (pseudoTag) { nsAutoString buffer; pseudoTag->ToString(buffer); fputs(NS_LossyConvertUTF16toASCII(buffer).get(), stdout); fputs(" ", stdout); } fputs("{}\n", stdout); } } static void VerifySameTree(nsStyleContext* aContext1, nsStyleContext* aContext2) { nsStyleContext* top1 = aContext1; nsStyleContext* top2 = aContext2; nsStyleContext* parent; for (;;) { parent = top1->GetParent(); if (!parent) break; top1 = parent; } for (;;) { parent = top2->GetParent(); if (!parent) break; top2 = parent; } NS_ASSERTION(top1 == top2, "Style contexts are not in the same style context tree"); } static void VerifyContextParent(nsPresContext* aPresContext, nsIFrame* aFrame, nsStyleContext* aContext, nsStyleContext* aParentContext) { // get the contexts not provided if (!aContext) { aContext = aFrame->StyleContext(); } if (!aParentContext) { // Get the correct parent context from the frame // - if the frame is a placeholder, we get the out of flow frame's context // as the parent context instead of asking the frame // get the parent context from the frame (indirectly) nsIFrame* providerFrame = aFrame->GetParentStyleContextFrame(); if (providerFrame) aParentContext = providerFrame->StyleContext(); // aParentContext could still be null } NS_ASSERTION(aContext, "Failure to get required contexts"); nsStyleContext* actualParentContext = aContext->GetParent(); if (aParentContext) { if (aParentContext != actualParentContext) { DumpContext(aFrame, aContext); if (aContext == aParentContext) { NS_ERROR("Using parent's style context"); } else { NS_ERROR("Wrong parent style context"); fputs("Wrong parent style context: ", stdout); DumpContext(nullptr, actualParentContext); fputs("should be using: ", stdout); DumpContext(nullptr, aParentContext); VerifySameTree(actualParentContext, aParentContext); fputs("\n", stdout); } } } else { if (actualParentContext) { NS_ERROR("Have parent context and shouldn't"); DumpContext(aFrame, aContext); fputs("Has parent context: ", stdout); DumpContext(nullptr, actualParentContext); fputs("Should be null\n\n", stdout); } } nsStyleContext* childStyleIfVisited = aContext->GetStyleIfVisited(); // Either childStyleIfVisited has aContext->GetParent()->GetStyleIfVisited() // as the parent or it has a different rulenode from aContext _and_ has // aContext->GetParent() as the parent. if (childStyleIfVisited && !((childStyleIfVisited->RuleNode() != aContext->RuleNode() && childStyleIfVisited->GetParent() == aContext->GetParent()) || childStyleIfVisited->GetParent() == aContext->GetParent()->GetStyleIfVisited())) { NS_ERROR("Visited style has wrong parent"); DumpContext(aFrame, aContext); fputs("\n", stdout); } } static void VerifyStyleTree(nsPresContext* aPresContext, nsIFrame* aFrame, nsStyleContext* aParentContext) { nsStyleContext* context = aFrame->StyleContext(); VerifyContextParent(aPresContext, aFrame, context, nullptr); nsIFrame::ChildListIterator lists(aFrame); for (; !lists.IsDone(); lists.Next()) { nsFrameList::Enumerator childFrames(lists.CurrentList()); for (; !childFrames.AtEnd(); childFrames.Next()) { nsIFrame* child = childFrames.get(); if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW)) { // only do frames that are in flow if (nsGkAtoms::placeholderFrame == child->GetType()) { // placeholder: first recurse and verify the out of flow frame, // then verify the placeholder's context nsIFrame* outOfFlowFrame = nsPlaceholderFrame::GetRealFrameForPlaceholder(child); // recurse to out of flow frame, letting the parent context get resolved do { VerifyStyleTree(aPresContext, outOfFlowFrame, nullptr); } while ((outOfFlowFrame = outOfFlowFrame->GetNextContinuation())); // verify placeholder using the parent frame's context as // parent context VerifyContextParent(aPresContext, child, nullptr, nullptr); } else { // regular frame VerifyStyleTree(aPresContext, child, nullptr); } } } } // do additional contexts int32_t contextIndex = 0; for (nsStyleContext* extraContext; (extraContext = aFrame->GetAdditionalStyleContext(contextIndex)); ++contextIndex) { VerifyContextParent(aPresContext, aFrame, extraContext, context); } } void RestyleManager::DebugVerifyStyleTree(nsIFrame* aFrame) { if (aFrame) { nsStyleContext* context = aFrame->StyleContext(); nsStyleContext* parentContext = context->GetParent(); VerifyStyleTree(mPresContext, aFrame, parentContext); } } #endif // DEBUG // aContent must be the content for the frame in question, which may be // :before/:after content static void TryStartingTransition(nsPresContext *aPresContext, nsIContent *aContent, nsStyleContext *aOldStyleContext, nsRefPtr *aNewStyleContext /* inout */) { if (!aContent || !aContent->IsElement()) { return; } // Notify the transition manager, and if it starts a transition, // it will give us back a transition-covering style rule which // we'll use to get *another* style context. We want to ignore // any already-running transitions, but cover up any that we're // currently starting with their start value so we don't start // them again for descendants that inherit that value. nsCOMPtr coverRule = aPresContext->TransitionManager()->StyleContextChanged( aContent->AsElement(), aOldStyleContext, *aNewStyleContext); if (coverRule) { nsCOMArray rules; rules.AppendObject(coverRule); *aNewStyleContext = aPresContext->StyleSet()-> ResolveStyleByAddingRules(*aNewStyleContext, rules); } } static inline dom::Element* ElementForStyleContext(nsIContent* aParentContent, nsIFrame* aFrame, nsCSSPseudoElements::Type aPseudoType) { // We don't expect XUL tree stuff here. NS_PRECONDITION(aPseudoType == nsCSSPseudoElements::ePseudo_NotPseudoElement || aPseudoType == nsCSSPseudoElements::ePseudo_AnonBox || aPseudoType < nsCSSPseudoElements::ePseudo_PseudoElementCount, "Unexpected pseudo"); // XXX see the comments about the various element confusion in // ElementRestyler::Restyle. if (aPseudoType == nsCSSPseudoElements::ePseudo_NotPseudoElement) { return aFrame->GetContent()->AsElement(); } if (aPseudoType == nsCSSPseudoElements::ePseudo_AnonBox) { return nullptr; } if (aPseudoType == nsCSSPseudoElements::ePseudo_firstLetter) { NS_ASSERTION(aFrame->GetType() == nsGkAtoms::letterFrame, "firstLetter pseudoTag without a nsFirstLetterFrame"); nsBlockFrame* block = nsBlockFrame::GetNearestAncestorBlock(aFrame); return block->GetContent()->AsElement(); } nsIContent* content = aParentContent ? aParentContent : aFrame->GetContent(); return content->AsElement(); } /** * FIXME: Temporary. Should merge with following function. */ static nsIFrame* GetPrevContinuationWithPossiblySameStyle(nsIFrame* aFrame) { // Account for {ib} splits when looking for "prevContinuation". In // particular, for the first-continuation of a part of an {ib} split we // want to use the special prevsibling of the special prevsibling of // aFrame, which should have the same style context as aFrame itself. // In particular, if aFrame is the first continuation of an inline part // of an {ib} split then its special prevsibling is a block, and the // special prevsibling of _that_ is an inline, just like aFrame. // Similarly, if aFrame is the first continuation of a block part of an // {ib} split (an {ib} wrapper block), then its special prevsibling is // an inline and the special prevsibling of that is either another {ib} // wrapper block block or null. nsIFrame *prevContinuation = aFrame->GetPrevContinuation(); if (!prevContinuation && (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL)) { // We're the first continuation, so we can just get the frame // property directly prevContinuation = static_cast( aFrame->Properties().Get(nsIFrame::IBSplitSpecialPrevSibling())); if (prevContinuation) { prevContinuation = static_cast( prevContinuation->Properties().Get(nsIFrame::IBSplitSpecialPrevSibling())); } } NS_ASSERTION(!prevContinuation || prevContinuation->GetContent() == aFrame->GetContent(), "unexpected content mismatch"); return prevContinuation; } /** * Get the previous continuation or similar special sibling (assuming * block/inline alternation), conditionally on it having the same style. * This assumes that we're not between resolving the two (i.e., that * they're both already resolved. */ static nsIFrame* GetPrevContinuationWithSameStyle(nsIFrame* aFrame) { nsIFrame* prevContinuation = GetPrevContinuationWithPossiblySameStyle(aFrame); if (!prevContinuation) { return nullptr; } nsStyleContext* prevStyle = prevContinuation->StyleContext(); nsStyleContext* selfStyle = aFrame->StyleContext(); if (prevStyle != selfStyle) { NS_ASSERTION(prevStyle->GetPseudo() != selfStyle->GetPseudo() || prevStyle->GetParent() != selfStyle->GetParent(), "continuations should have the same style context"); prevContinuation = nullptr; } return prevContinuation; } /** * Get the next continuation or similar special sibling (assuming * block/inline alternation), conditionally on it having the same style. * * Since this is used when deciding to copy the new style context, it * takes as an argument the old style context to check if the style is * the same. When it is used in other contexts (i.e., where the next * continuation would already have the new style context), the current * style context should be passed. */ static nsIFrame* GetNextContinuationWithSameStyle(nsIFrame* aFrame, nsStyleContext* aOldStyleContext) { // See GetPrevContinuationWithSameStyle about {ib} splits. nsIFrame *nextContinuation = aFrame->GetNextContinuation(); if (!nextContinuation && (aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL)) { // We're the last continuation, so we have to hop back to the first // before getting the frame property nextContinuation = static_cast(aFrame->FirstContinuation()-> Properties().Get(nsIFrame::IBSplitSpecialSibling())); if (nextContinuation) { nextContinuation = static_cast( nextContinuation->Properties().Get(nsIFrame::IBSplitSpecialSibling())); } } if (!nextContinuation) { return nullptr; } NS_ASSERTION(nextContinuation->GetContent() == aFrame->GetContent(), "unexpected content mismatch"); nsStyleContext* nextStyle = nextContinuation->StyleContext(); if (nextStyle != aOldStyleContext) { NS_ASSERTION(aOldStyleContext->GetPseudo() != nextStyle->GetPseudo() || aOldStyleContext->GetParent() != nextStyle->GetParent(), "continuations should have the same style context"); nextContinuation = nullptr; } return nextContinuation; } nsresult RestyleManager::ReparentStyleContext(nsIFrame* aFrame) { if (nsGkAtoms::placeholderFrame == aFrame->GetType()) { // Also reparent the out-of-flow and all its continuations. nsIFrame* outOfFlow = nsPlaceholderFrame::GetRealFrameForPlaceholder(aFrame); NS_ASSERTION(outOfFlow, "no out-of-flow frame"); do { ReparentStyleContext(outOfFlow); } while ((outOfFlow = outOfFlow->GetNextContinuation())); } // DO NOT verify the style tree before reparenting. The frame // tree has already been changed, so this check would just fail. nsStyleContext* oldContext = aFrame->StyleContext(); nsRefPtr newContext; nsIFrame* providerFrame = aFrame->GetParentStyleContextFrame(); bool isChild = providerFrame && providerFrame->GetParent() == aFrame; nsStyleContext* newParentContext = nullptr; nsIFrame* providerChild = nullptr; if (isChild) { ReparentStyleContext(providerFrame); newParentContext = providerFrame->StyleContext(); providerChild = providerFrame; } else if (providerFrame) { newParentContext = providerFrame->StyleContext(); } else { NS_NOTREACHED("Reparenting something that has no usable parent? " "Shouldn't happen!"); } // XXX need to do something here to produce the correct style context for // an IB split whose first inline part is inside a first-line frame. // Currently the first IB anonymous block's style context takes the first // part's style context as parent, which is wrong since first-line style // should not apply to the anonymous block. #ifdef DEBUG { // Check that our assumption that continuations of the same // pseudo-type and with the same style context parent have the // same style context is valid before the reresolution. (We need // to check the pseudo-type and style context parent because of // :first-letter and :first-line, where we create styled and // unstyled letter/line frames distinguished by pseudo-type, and // then need to distinguish their descendants based on having // different parents.) nsIFrame *nextContinuation = aFrame->GetNextContinuation(); if (nextContinuation) { nsStyleContext *nextContinuationContext = nextContinuation->StyleContext(); NS_ASSERTION(oldContext == nextContinuationContext || oldContext->GetPseudo() != nextContinuationContext->GetPseudo() || oldContext->GetParent() != nextContinuationContext->GetParent(), "continuations should have the same style context"); } } #endif nsIFrame *prevContinuation = GetPrevContinuationWithPossiblySameStyle(aFrame); nsStyleContext *prevContinuationContext; bool copyFromContinuation = prevContinuation && (prevContinuationContext = prevContinuation->StyleContext()) ->GetPseudo() == oldContext->GetPseudo() && prevContinuationContext->GetParent() == newParentContext; if (copyFromContinuation) { // Just use the style context from the frame's previous // continuation (see assertion about aFrame->GetNextContinuation() // above, which we would have previously hit for aFrame's previous // continuation). newContext = prevContinuationContext; } else { nsIFrame* parentFrame = aFrame->GetParent(); Element* element = ElementForStyleContext(parentFrame ? parentFrame->GetContent() : nullptr, aFrame, oldContext->GetPseudoType()); newContext = mPresContext->StyleSet()-> ReparentStyleContext(oldContext, newParentContext, element); } if (newContext) { if (newContext != oldContext) { // We probably don't want to initiate transitions from // ReparentStyleContext, since we call it during frame // construction rather than in response to dynamic changes. // Also see the comment at the start of // nsTransitionManager::ConsiderStartingTransition. #if 0 if (!copyFromContinuation) { TryStartingTransition(mPresContext, aFrame->GetContent(), oldContext, &newContext); } #endif // Make sure to call CalcStyleDifference so that the new context ends // up resolving all the structs the old context resolved. if (!copyFromContinuation) { DebugOnly styleChange = oldContext->CalcStyleDifference(newContext, nsChangeHint(0)); // The style change is always 0 because we have the same rulenode and // CalcStyleDifference optimizes us away. That's OK, though: // reparenting should never trigger a frame reconstruct, and whenever // it's happening we already plan to reflow and repaint the frames. NS_ASSERTION(!(styleChange & nsChangeHint_ReconstructFrame), "Our frame tree is likely to be bogus!"); } aFrame->SetStyleContext(newContext); nsIFrame::ChildListIterator lists(aFrame); for (; !lists.IsDone(); lists.Next()) { nsFrameList::Enumerator childFrames(lists.CurrentList()); for (; !childFrames.AtEnd(); childFrames.Next()) { nsIFrame* child = childFrames.get(); // only do frames that are in flow if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW) && child != providerChild) { #ifdef DEBUG if (nsGkAtoms::placeholderFrame == child->GetType()) { nsIFrame* outOfFlowFrame = nsPlaceholderFrame::GetRealFrameForPlaceholder(child); NS_ASSERTION(outOfFlowFrame, "no out-of-flow frame"); NS_ASSERTION(outOfFlowFrame != providerChild, "Out of flow provider?"); } #endif ReparentStyleContext(child); } } } // If this frame is part of an IB split, then the style context of // the next part of the split might be a child of our style context. // Reparent its style context just in case one of our ancestors // (split or not) hasn't done so already). It's not a problem to // reparent the same frame twice because the "if (newContext != // oldContext)" check will prevent us from redoing work. if ((aFrame->GetStateBits() & NS_FRAME_IS_SPECIAL) && !aFrame->GetPrevContinuation()) { nsIFrame* sib = static_cast (aFrame->Properties().Get(nsIFrame::IBSplitSpecialSibling())); if (sib) { ReparentStyleContext(sib); } } // do additional contexts int32_t contextIndex = 0; for (nsStyleContext* oldExtraContext; (oldExtraContext = aFrame->GetAdditionalStyleContext(contextIndex)); ++contextIndex) { nsRefPtr newExtraContext; newExtraContext = mPresContext->StyleSet()-> ReparentStyleContext(oldExtraContext, newContext, nullptr); if (newExtraContext) { if (newExtraContext != oldExtraContext) { // Make sure to call CalcStyleDifference so that the new // context ends up resolving all the structs the old context // resolved. DebugOnly styleChange = oldExtraContext->CalcStyleDifference(newExtraContext, nsChangeHint(0)); // The style change is always 0 because we have the same // rulenode and CalcStyleDifference optimizes us away. That's // OK, though: reparenting should never trigger a frame // reconstruct, and whenever it's happening we already plan to // reflow and repaint the frames. NS_ASSERTION(!(styleChange & nsChangeHint_ReconstructFrame), "Our frame tree is likely to be bogus!"); } aFrame->SetAdditionalStyleContext(contextIndex, newExtraContext); } } #ifdef DEBUG VerifyStyleTree(mPresContext, aFrame, newParentContext); #endif } } return NS_OK; } ElementRestyler::ElementRestyler(nsPresContext* aPresContext, nsIFrame* aFrame, nsStyleChangeList* aChangeList, nsChangeHint aHintsHandledByAncestors, RestyleTracker& aRestyleTracker, TreeMatchContext& aTreeMatchContext, nsTArray& aVisibleKidsOfHiddenElement) : mPresContext(aPresContext) , mFrame(aFrame) , mParentContent(nullptr) // XXXldb Why does it make sense to use aParentContent? (See // comment above assertion at start of ElementRestyler::Restyle.) , mContent(mFrame->GetContent() ? mFrame->GetContent() : mParentContent) , mChangeList(aChangeList) , mHintsHandled(NS_SubtractHint(aHintsHandledByAncestors, NS_HintsNotHandledForDescendantsIn(aHintsHandledByAncestors))) , mParentFrameHintsNotHandledForDescendants(nsChangeHint(0)) , mHintsNotHandledForDescendants(nsChangeHint(0)) , mRestyleTracker(aRestyleTracker) , mTreeMatchContext(aTreeMatchContext) , mResolvedChild(nullptr) #ifdef ACCESSIBILITY , mDesiredA11yNotifications(eSendAllNotifications) , mKidsDesiredA11yNotifications(mDesiredA11yNotifications) , mOurA11yNotification(eDontNotify) , mVisibleKidsOfHiddenElement(aVisibleKidsOfHiddenElement) #endif { } ElementRestyler::ElementRestyler(const ElementRestyler& aParentRestyler, nsIFrame* aFrame, uint32_t aConstructorFlags) : mPresContext(aParentRestyler.mPresContext) , mFrame(aFrame) , mParentContent(aParentRestyler.mContent) // XXXldb Why does it make sense to use aParentContent? (See // comment above assertion at start of ElementRestyler::Restyle.) , mContent(mFrame->GetContent() ? mFrame->GetContent() : mParentContent) , mChangeList(aParentRestyler.mChangeList) , mHintsHandled(NS_SubtractHint(aParentRestyler.mHintsHandled, NS_HintsNotHandledForDescendantsIn(aParentRestyler.mHintsHandled))) , mParentFrameHintsNotHandledForDescendants( aParentRestyler.mHintsNotHandledForDescendants) , mHintsNotHandledForDescendants(nsChangeHint(0)) , mRestyleTracker(aParentRestyler.mRestyleTracker) , mTreeMatchContext(aParentRestyler.mTreeMatchContext) , mResolvedChild(nullptr) #ifdef ACCESSIBILITY , mDesiredA11yNotifications(aParentRestyler.mKidsDesiredA11yNotifications) , mKidsDesiredA11yNotifications(mDesiredA11yNotifications) , mOurA11yNotification(eDontNotify) , mVisibleKidsOfHiddenElement(aParentRestyler.mVisibleKidsOfHiddenElement) #endif { if (aConstructorFlags & FOR_OUT_OF_FLOW_CHILD) { // Note that the out-of-flow may not be a geometric descendant of // the frame where we started the reresolve. Therefore, even if // mHintsHandled already includes nsChangeHint_AllReflowHints we // don't want to pass that on to the out-of-flow reresolve, since // that can lead to the out-of-flow not getting reflowed when it // should be (eg a reresolve starting at that involves // reflowing the would miss reflowing fixed-pos nodes that // also need reflow). In the cases when the out-of-flow _is_ a // geometric descendant of a frame we already have a reflow hint // for, reflow coalescing should keep us from doing the work twice. mHintsHandled = NS_SubtractHint(mHintsHandled, nsChangeHint_AllReflowHints); } } ElementRestyler::ElementRestyler(ParentContextFromChildFrame, const ElementRestyler& aParentRestyler, nsIFrame* aFrame) : mPresContext(aParentRestyler.mPresContext) , mFrame(aFrame) , mParentContent(aParentRestyler.mParentContent) // XXXldb Why does it make sense to use aParentContent? (See // comment above assertion at start of ElementRestyler::Restyle.) , mContent(mFrame->GetContent() ? mFrame->GetContent() : mParentContent) , mChangeList(aParentRestyler.mChangeList) , mHintsHandled(NS_SubtractHint(aParentRestyler.mHintsHandled, NS_HintsNotHandledForDescendantsIn(aParentRestyler.mHintsHandled))) , mParentFrameHintsNotHandledForDescendants( // assume the worst nsChangeHint_Hints_NotHandledForDescendants) , mHintsNotHandledForDescendants(nsChangeHint(0)) , mRestyleTracker(aParentRestyler.mRestyleTracker) , mTreeMatchContext(aParentRestyler.mTreeMatchContext) , mResolvedChild(nullptr) #ifdef ACCESSIBILITY , mDesiredA11yNotifications(aParentRestyler.mDesiredA11yNotifications) , mKidsDesiredA11yNotifications(mDesiredA11yNotifications) , mOurA11yNotification(eDontNotify) , mVisibleKidsOfHiddenElement(aParentRestyler.mVisibleKidsOfHiddenElement) #endif { } void ElementRestyler::CaptureChange(nsStyleContext* aOldContext, nsStyleContext* aNewContext, nsChangeHint aChangeToAssume) { // Check some invariants about replacing one style context with another. NS_ASSERTION(aOldContext->GetPseudo() == aNewContext->GetPseudo(), "old and new style contexts should have the same pseudo"); NS_ASSERTION(aOldContext->GetPseudoType() == aNewContext->GetPseudoType(), "old and new style contexts should have the same pseudo"); nsChangeHint ourChange = aOldContext->CalcStyleDifference(aNewContext, mParentFrameHintsNotHandledForDescendants); NS_ASSERTION(!(ourChange & nsChangeHint_AllReflowHints) || (ourChange & nsChangeHint_NeedReflow), "Reflow hint bits set without actually asking for a reflow"); // nsChangeHint_UpdateEffects is inherited, but it can be set due to changes // in inherited properties (fill and stroke). Avoid propagating it into // text nodes. if ((ourChange & nsChangeHint_UpdateEffects) && mContent && !mContent->IsElement()) { ourChange = NS_SubtractHint(ourChange, nsChangeHint_UpdateEffects); } NS_UpdateHint(ourChange, aChangeToAssume); if (NS_UpdateHint(mHintsHandled, ourChange)) { if (!(ourChange & nsChangeHint_ReconstructFrame) || mContent) { mChangeList->AppendChange(mFrame, mContent, ourChange); } } NS_UpdateHint(mHintsNotHandledForDescendants, NS_HintsNotHandledForDescendantsIn(ourChange)); } /** * Recompute style for mFrame (which should not have a prev continuation * with the same style), all of its next continuations with the same * style, and all special siblings of the same type (either block or * inline, skipping the intermediates of the other type) and accumulate * changes into mChangeList given that mHintsHandled is already accumulated * for an ancestor. * mParentContent is the content node used to resolve the parent style * context. This means that, for pseudo-elements, it is the content * that should be used for selector matching (rather than the fake * content node attached to the frame). */ void ElementRestyler::Restyle(nsRestyleHint aRestyleHint) { // It would be nice if we could make stronger assertions here; they // would let us simplify the ?: expressions below setting |content| // and |pseudoContent| in sensible ways as well as making what // |content| and |pseudoContent| mean, and their relationship to // |mFrame->GetContent()|, make more sense. However, we can't, // because of frame trees like the one in // https://bugzilla.mozilla.org/show_bug.cgi?id=472353#c14 . Once we // fix bug 242277 we should be able to make this make more sense. NS_ASSERTION(mFrame->GetContent() || !mParentContent || !mParentContent->GetParent(), "frame must have content (unless at the top of the tree)"); NS_ASSERTION(!GetPrevContinuationWithSameStyle(mFrame), "should not be trying to restyle this frame separately"); if (mContent && mContent->IsElement()) { mContent->OwnerDoc()->FlushPendingLinkUpdates(); RestyleTracker::RestyleData restyleData; if (mRestyleTracker.GetRestyleData(mContent->AsElement(), &restyleData)) { if (NS_UpdateHint(mHintsHandled, restyleData.mChangeHint)) { mChangeList->AppendChange(mFrame, mContent, restyleData.mChangeHint); } aRestyleHint = nsRestyleHint(aRestyleHint | restyleData.mRestyleHint); } } nsRestyleHint childRestyleHint = aRestyleHint; if (childRestyleHint == eRestyle_Self) { childRestyleHint = nsRestyleHint(0); } { nsRefPtr oldContext = mFrame->StyleContext(); // TEMPORARY (until bug 918064): Call RestyleSelf for each // continuation or block-in-inline sibling. for (nsIFrame* f = mFrame; f; f = GetNextContinuationWithSameStyle(f, oldContext)) { RestyleSelf(f, aRestyleHint); } } RestyleChildren(childRestyleHint); } void ElementRestyler::RestyleSelf(nsIFrame* aSelf, nsRestyleHint aRestyleHint) { // XXXldb get new context from prev-in-flow if possible, to avoid // duplication. (Or should we just let |GetContext| handle that?) // Getting the hint would be nice too, but that's harder. // XXXbryner we may be able to avoid some of the refcounting goop here. // We do need a reference to oldContext for the lifetime of this function, and it's possible // that the frame has the last reference to it, so AddRef it here. nsChangeHint assumeDifferenceHint = NS_STYLE_HINT_NONE; nsRefPtr oldContext = aSelf->StyleContext(); nsStyleSet* styleSet = mPresContext->StyleSet(); #ifdef ACCESSIBILITY mWasFrameVisible = nsIPresShell::IsAccessibilityActive() ? oldContext->StyleVisibility()->IsVisible() : false; #endif nsIAtom* const pseudoTag = oldContext->GetPseudo(); const nsCSSPseudoElements::Type pseudoType = oldContext->GetPseudoType(); nsStyleContext* parentContext; // Get the frame providing the parent style context. If it is a // child, then resolve the provider first. nsIFrame* providerFrame = aSelf->GetParentStyleContextFrame(); bool isChild = providerFrame && providerFrame->GetParent() == aSelf; if (!isChild) { if (providerFrame) parentContext = providerFrame->StyleContext(); else parentContext = nullptr; } else { MOZ_ASSERT(providerFrame->GetContent() == aSelf->GetContent(), "Postcondition for GetParentStyleContextFrame() violated. " "That means we need to add the current element to the " "ancestor filter."); // resolve the provider here (before aSelf below). // assumeDifferenceHint forces the parent's change to be also // applied to this frame, no matter what // nsStyleContext::CalcStyleDifference says. CalcStyleDifference // can't be trusted because it assumes any changes to the parent // style context provider will be automatically propagated to // the frame(s) with child style contexts. ElementRestyler providerRestyler(PARENT_CONTEXT_FROM_CHILD_FRAME, *this, providerFrame); providerRestyler.Restyle(aRestyleHint); assumeDifferenceHint = providerRestyler.HintsHandledForFrame(); // The provider's new context becomes the parent context of // aSelf's context. parentContext = providerFrame->StyleContext(); // Set |mResolvedChild| so we don't bother resolving the // provider again. mResolvedChild = providerFrame; } if (providerFrame != aSelf->GetParent()) { // We don't actually know what the parent style context's // non-inherited hints were, so assume the worst. mParentFrameHintsNotHandledForDescendants = nsChangeHint_Hints_NotHandledForDescendants; } // do primary context nsRefPtr newContext; nsIFrame *prevContinuation = GetPrevContinuationWithPossiblySameStyle(aSelf); nsStyleContext *prevContinuationContext; bool copyFromContinuation = prevContinuation && (prevContinuationContext = prevContinuation->StyleContext()) ->GetPseudo() == oldContext->GetPseudo() && prevContinuationContext->GetParent() == parentContext; if (copyFromContinuation) { // Just use the style context from the frame's previous // continuation. newContext = prevContinuationContext; } else if (pseudoTag == nsCSSAnonBoxes::mozNonElement) { NS_ASSERTION(aSelf->GetContent(), "non pseudo-element frame without content node"); newContext = styleSet->ResolveStyleForNonElement(parentContext); } else if (!aRestyleHint && !prevContinuation) { // Unfortunately, if prevContinuation is non-null then we may have // already stolen the restyle tracker entry for this element while // processing prevContinuation. So we don't know whether aRestyleHint // should really be 0 here or whether it should be eRestyle_Self. Be // pessimistic and force an actual reresolve in that situation. The good // news is that in the common case when prevContinuation is non-null we // just used prevContinuationContext anyway and aren't reaching this code // to start with. newContext = styleSet->ReparentStyleContext(oldContext, parentContext, ElementForStyleContext(mParentContent, aSelf, pseudoType)); } else if (pseudoType == nsCSSPseudoElements::ePseudo_AnonBox) { newContext = styleSet->ResolveAnonymousBoxStyle(pseudoTag, parentContext); } else { Element* element = ElementForStyleContext(mParentContent, aSelf, pseudoType); if (pseudoTag) { if (pseudoTag == nsCSSPseudoElements::before || pseudoTag == nsCSSPseudoElements::after) { // XXX what other pseudos do we need to treat like this? newContext = styleSet->ProbePseudoElementStyle(element, pseudoType, parentContext, mTreeMatchContext); if (!newContext) { // This pseudo should no longer exist; gotta reframe NS_UpdateHint(mHintsHandled, nsChangeHint_ReconstructFrame); mChangeList->AppendChange(aSelf, element, nsChangeHint_ReconstructFrame); // We're reframing anyway; just keep the same context newContext = oldContext; } } else { // Don't expect XUL tree stuff here, since it needs a comparator and // all. NS_ASSERTION(pseudoType < nsCSSPseudoElements::ePseudo_PseudoElementCount, "Unexpected pseudo type"); newContext = styleSet->ResolvePseudoElementStyle(element, pseudoType, parentContext); } } else { NS_ASSERTION(aSelf->GetContent(), "non pseudo-element frame without content node"); // Skip flex-item style fixup for anonymous subtrees: TreeMatchContext::AutoFlexItemStyleFixupSkipper flexFixupSkipper(mTreeMatchContext, element->IsRootOfNativeAnonymousSubtree()); newContext = styleSet->ResolveStyleFor(element, parentContext, mTreeMatchContext); } } MOZ_ASSERT(newContext); if (!parentContext) { if (oldContext->RuleNode() == newContext->RuleNode() && oldContext->IsLinkContext() == newContext->IsLinkContext() && oldContext->RelevantLinkVisited() == newContext->RelevantLinkVisited()) { // We're the root of the style context tree and the new style // context returned has the same rule node. This means that // we can use FindChildWithRules to keep a lot of the old // style contexts around. However, we need to start from the // same root. newContext = oldContext; } } if (newContext != oldContext) { if (!copyFromContinuation) { TryStartingTransition(mPresContext, aSelf->GetContent(), oldContext, &newContext); CaptureChange(oldContext, newContext, assumeDifferenceHint); } if (!(mHintsHandled & nsChangeHint_ReconstructFrame)) { // If the frame gets regenerated, let it keep its old context, // which is important to maintain various invariants about // frame types matching their style contexts. // Note that this check even makes sense if we didn't call // CaptureChange because of copyFromContinuation being true, // since we'll have copied the existing context from the // previous continuation, so newContext == oldContext. aSelf->SetStyleContext(newContext); } } oldContext = nullptr; // do additional contexts // XXXbz might be able to avoid selector matching here in some // cases; won't worry about it for now. int32_t contextIndex = 0; for (nsStyleContext* oldExtraContext; (oldExtraContext = aSelf->GetAdditionalStyleContext(contextIndex)); ++contextIndex) { nsRefPtr newExtraContext; nsIAtom* const extraPseudoTag = oldExtraContext->GetPseudo(); const nsCSSPseudoElements::Type extraPseudoType = oldExtraContext->GetPseudoType(); NS_ASSERTION(extraPseudoTag && extraPseudoTag != nsCSSAnonBoxes::mozNonElement, "extra style context is not pseudo element"); if (extraPseudoType == nsCSSPseudoElements::ePseudo_AnonBox) { newExtraContext = styleSet->ResolveAnonymousBoxStyle(extraPseudoTag, newContext); } else { // Don't expect XUL tree stuff here, since it needs a comparator and // all. NS_ASSERTION(extraPseudoType < nsCSSPseudoElements::ePseudo_PseudoElementCount, "Unexpected type"); newExtraContext = styleSet->ResolvePseudoElementStyle(mContent->AsElement(), extraPseudoType, newContext); } MOZ_ASSERT(newExtraContext); if (oldExtraContext != newExtraContext) { CaptureChange(oldExtraContext, newExtraContext, assumeDifferenceHint); if (!(mHintsHandled & nsChangeHint_ReconstructFrame)) { aSelf->SetAdditionalStyleContext(contextIndex, newExtraContext); } } } } void ElementRestyler::RestyleChildren(nsRestyleHint aChildRestyleHint) { RestyleUndisplayedChildren(aChildRestyleHint); // Check whether we might need to create a new ::before frame. // There's no need to do this if we're planning to reframe already // or if we're not forcing restyles on kids. // It's also important to check mHintsHandled since we use // mFrame->StyleContext(), which is out of date if mHintsHandled has a // ReconstructFrame hint. Using an out of date style context could // trigger assertions about mismatched rule trees. if (!(mHintsHandled & nsChangeHint_ReconstructFrame) && aChildRestyleHint) { RestyleBeforePseudo(); } // There is no need to waste time crawling into a frame's children // on a frame change. The act of reconstructing frames will force // new style contexts to be resolved on all of this frame's // descendants anyway, so we want to avoid wasting time processing // style contexts that we're just going to throw away anyway. - dwh // It's also important to check mHintsHandled since reresolving the // kids would use mFrame->StyleContext(), which is out of date if // mHintsHandled has a ReconstructFrame hint; doing this could trigger // assertions about mismatched rule trees. nsIFrame *lastContinuation; if (!(mHintsHandled & nsChangeHint_ReconstructFrame)) { InitializeAccessibilityNotifications(); for (nsIFrame* f = mFrame; f; f = GetNextContinuationWithSameStyle(f, f->StyleContext())) { lastContinuation = f; RestyleContentChildren(f, aChildRestyleHint); } SendAccessibilityNotifications(); } // Check whether we might need to create a new ::after frame. // See comments above regarding :before. if (!(mHintsHandled & nsChangeHint_ReconstructFrame) && aChildRestyleHint) { RestyleAfterPseudo(lastContinuation); } } void ElementRestyler::RestyleUndisplayedChildren(nsRestyleHint aChildRestyleHint) { // When the root element is display:none, we still construct *some* // frames that have the root element as their mContent, down to the // DocElementContainingBlock. bool checkUndisplayed; nsIContent* undisplayedParent; nsCSSFrameConstructor* frameConstructor = mPresContext->FrameConstructor(); if (mFrame->StyleContext()->GetPseudo()) { checkUndisplayed = mFrame == frameConstructor-> GetDocElementContainingBlock(); undisplayedParent = nullptr; } else { checkUndisplayed = !!mFrame->GetContent(); undisplayedParent = mFrame->GetContent(); } if (checkUndisplayed && // No need to do this if we're planning to reframe already. // It's also important to check mHintsHandled since we use // mFrame->StyleContext(), which is out of date if mHintsHandled // has a ReconstructFrame hint. Using an out of date style // context could trigger assertions about mismatched rule trees. !(mHintsHandled & nsChangeHint_ReconstructFrame)) { UndisplayedNode* undisplayed = frameConstructor->GetAllUndisplayedContentIn(undisplayedParent); for (TreeMatchContext::AutoAncestorPusher pushAncestor(undisplayed, mTreeMatchContext, undisplayedParent ? undisplayedParent->AsElement() : nullptr); undisplayed; undisplayed = undisplayed->mNext) { NS_ASSERTION(undisplayedParent || undisplayed->mContent == mPresContext->Document()->GetRootElement(), "undisplayed node child of null must be root"); NS_ASSERTION(!undisplayed->mStyle->GetPseudo(), "Shouldn't have random pseudo style contexts in the " "undisplayed map"); // Get the parent of the undisplayed content and check if it is a XBL // children element. Push the children element as an ancestor here because it does // not have a frame and would not otherwise be pushed as an ancestor. nsIContent* parent = undisplayed->mContent->GetParent(); bool pushInsertionPoint = parent && parent->IsActiveChildrenElement(); TreeMatchContext::AutoAncestorPusher insertionPointPusher(pushInsertionPoint, mTreeMatchContext, parent && parent->IsElement() ? parent->AsElement() : nullptr); nsRestyleHint thisChildHint = aChildRestyleHint; RestyleTracker::RestyleData undisplayedRestyleData; if (mRestyleTracker.GetRestyleData(undisplayed->mContent->AsElement(), &undisplayedRestyleData)) { thisChildHint = nsRestyleHint(thisChildHint | undisplayedRestyleData.mRestyleHint); } nsRefPtr undisplayedContext; nsStyleSet* styleSet = mPresContext->StyleSet(); if (thisChildHint) { undisplayedContext = styleSet->ResolveStyleFor(undisplayed->mContent->AsElement(), mFrame->StyleContext(), mTreeMatchContext); } else { undisplayedContext = styleSet->ReparentStyleContext(undisplayed->mStyle, mFrame->StyleContext(), undisplayed->mContent->AsElement()); } const nsStyleDisplay* display = undisplayedContext->StyleDisplay(); if (display->mDisplay != NS_STYLE_DISPLAY_NONE) { NS_ASSERTION(undisplayed->mContent, "Must have undisplayed content"); mChangeList->AppendChange(nullptr, undisplayed->mContent, NS_STYLE_HINT_FRAMECHANGE); // The node should be removed from the undisplayed map when // we reframe it. } else { // update the undisplayed node with the new context undisplayed->mStyle = undisplayedContext; } } } } void ElementRestyler::RestyleBeforePseudo() { // Make sure not to do this for pseudo-frames or frames that // can't have generated content. if (!mFrame->StyleContext()->GetPseudo() && ((mFrame->GetStateBits() & NS_FRAME_MAY_HAVE_GENERATED_CONTENT) || // Our content insertion frame might have gotten flagged (mFrame->GetContentInsertionFrame()->GetStateBits() & NS_FRAME_MAY_HAVE_GENERATED_CONTENT))) { // Check for a new :before pseudo and an existing :before // frame, but only if the frame is the first continuation. nsIFrame* prevContinuation = mFrame->GetPrevContinuation(); if (!prevContinuation) { // Checking for a :before frame is cheaper than getting the // :before style context. if (!nsLayoutUtils::GetBeforeFrame(mFrame) && nsLayoutUtils::HasPseudoStyle(mFrame->GetContent(), mFrame->StyleContext(), nsCSSPseudoElements::ePseudo_before, mPresContext)) { // Have to create the new :before frame NS_UpdateHint(mHintsHandled, nsChangeHint_ReconstructFrame); mChangeList->AppendChange(mFrame, mContent, nsChangeHint_ReconstructFrame); } } } } /** * aFrame is the last continuation or block-in-inline sibling that this * ElementRestyler is restyling. */ void ElementRestyler::RestyleAfterPseudo(nsIFrame* aFrame) { // Make sure not to do this for pseudo-frames or frames that // can't have generated content. if (!aFrame->StyleContext()->GetPseudo() && ((aFrame->GetStateBits() & NS_FRAME_MAY_HAVE_GENERATED_CONTENT) || // Our content insertion frame might have gotten flagged (aFrame->GetContentInsertionFrame()->GetStateBits() & NS_FRAME_MAY_HAVE_GENERATED_CONTENT))) { // Check for new :after content, but only if the frame is the // last continuation. nsIFrame* nextContinuation = aFrame->GetNextContinuation(); if (!nextContinuation) { // Getting the :after frame is more expensive than getting the pseudo // context, so get the pseudo context first. if (nsLayoutUtils::HasPseudoStyle(aFrame->GetContent(), aFrame->StyleContext(), nsCSSPseudoElements::ePseudo_after, mPresContext) && !nsLayoutUtils::GetAfterFrame(aFrame)) { // have to create the new :after frame NS_UpdateHint(mHintsHandled, nsChangeHint_ReconstructFrame); mChangeList->AppendChange(aFrame, mContent, nsChangeHint_ReconstructFrame); } } } } void ElementRestyler::InitializeAccessibilityNotifications() { #ifdef ACCESSIBILITY // Notify a11y for primary frame only if it's a root frame of visibility // changes or its parent frame was hidden while it stays visible and // it is not inside a {ib} split or is the first frame of {ib} split. if (nsIPresShell::IsAccessibilityActive() && !mFrame->GetPrevContinuation() && !mFrame->FrameIsNonFirstInIBSplit()) { if (mDesiredA11yNotifications == eSendAllNotifications) { bool isFrameVisible = mFrame->StyleVisibility()->IsVisible(); if (isFrameVisible != mWasFrameVisible) { if (isFrameVisible) { // Notify a11y the element (perhaps with its children) was shown. // We don't fall into this case if this element gets or stays shown // while its parent becomes hidden. mKidsDesiredA11yNotifications = eSkipNotifications; mOurA11yNotification = eNotifyShown; } else { // The element is being hidden; its children may stay visible, or // become visible after being hidden previously. If we'll find // visible children then we should notify a11y about that as if // they were inserted into tree. Notify a11y this element was // hidden. mKidsDesiredA11yNotifications = eNotifyIfShown; mOurA11yNotification = eNotifyHidden; } } } else if (mDesiredA11yNotifications == eNotifyIfShown && mFrame->StyleVisibility()->IsVisible()) { // Notify a11y that element stayed visible while its parent was // hidden. mVisibleKidsOfHiddenElement.AppendElement(mFrame->GetContent()); mKidsDesiredA11yNotifications = eSkipNotifications; } } #endif } void ElementRestyler::RestyleContentChildren(nsIFrame* aParent, nsRestyleHint aChildRestyleHint) { nsIFrame::ChildListIterator lists(aParent); for (TreeMatchContext::AutoAncestorPusher pushAncestor(!lists.IsDone(), mTreeMatchContext, mContent && mContent->IsElement() ? mContent->AsElement() : nullptr); !lists.IsDone(); lists.Next()) { nsFrameList::Enumerator childFrames(lists.CurrentList()); for (; !childFrames.AtEnd(); childFrames.Next()) { nsIFrame* child = childFrames.get(); // Out-of-flows are reached through their placeholders. Continuations // and block-in-inline splits are reached through those chains. if (!(child->GetStateBits() & NS_FRAME_OUT_OF_FLOW) && !GetPrevContinuationWithSameStyle(child)) { // Get the parent of the child frame's content and check if it // is a XBL children element. Push the children element as an // ancestor here because it does not have a frame and would not // otherwise be pushed as an ancestor. // Check if the frame has a content because |child| may be a // nsPageFrame that does not have a content. nsIContent* parent = child->GetContent() ? child->GetContent()->GetParent() : nullptr; bool pushInsertionPoint = parent && parent->IsActiveChildrenElement(); TreeMatchContext::AutoAncestorPusher insertionPointPusher(pushInsertionPoint, mTreeMatchContext, parent && parent->IsElement() ? parent->AsElement() : nullptr); // only do frames that are in flow if (nsGkAtoms::placeholderFrame == child->GetType()) { // placeholder // get out of flow frame and recur there nsIFrame* outOfFlowFrame = nsPlaceholderFrame::GetRealFrameForPlaceholder(child); NS_ASSERTION(outOfFlowFrame, "no out-of-flow frame"); NS_ASSERTION(outOfFlowFrame != mResolvedChild, "out-of-flow frame not a true descendant"); // |nsFrame::GetParentStyleContextFrame| checks being out // of flow so that this works correctly. do { if (GetPrevContinuationWithSameStyle(outOfFlowFrame)) { // Later continuations are likely restyled as a result of // the restyling of the previous continuation. // (Currently that's always true, but it's likely to // change if we implement overflow:fragments or similar.) continue; } ElementRestyler oofRestyler(*this, outOfFlowFrame, FOR_OUT_OF_FLOW_CHILD); oofRestyler.Restyle(aChildRestyleHint); } while ((outOfFlowFrame = outOfFlowFrame->GetNextContinuation())); // reresolve placeholder's context under the same parent // as the out-of-flow frame ElementRestyler phRestyler(*this, child, 0); phRestyler.Restyle(aChildRestyleHint); } else { // regular child frame if (child != mResolvedChild) { ElementRestyler childRestyler(*this, child, 0); childRestyler.Restyle(aChildRestyleHint); } } } } } // XXX need to do overflow frames??? } void ElementRestyler::SendAccessibilityNotifications() { #ifdef ACCESSIBILITY // Send notifications about visibility changes. if (mOurA11yNotification == eNotifyShown) { nsAccessibilityService* accService = nsIPresShell::AccService(); if (accService) { nsIPresShell* presShell = mFrame->PresContext()->GetPresShell(); nsIContent* content = mFrame->GetContent(); accService->ContentRangeInserted(presShell, content->GetParent(), content, content->GetNextSibling()); } } else if (mOurA11yNotification == eNotifyHidden) { nsAccessibilityService* accService = nsIPresShell::AccService(); if (accService) { nsIPresShell* presShell = mFrame->PresContext()->GetPresShell(); nsIContent* content = mFrame->GetContent(); accService->ContentRemoved(presShell, content->GetParent(), content); // Process children staying shown. uint32_t visibleContentCount = mVisibleKidsOfHiddenElement.Length(); for (uint32_t idx = 0; idx < visibleContentCount; idx++) { nsIContent* childContent = mVisibleKidsOfHiddenElement[idx]; accService->ContentRangeInserted(presShell, childContent->GetParent(), childContent, childContent->GetNextSibling()); } mVisibleKidsOfHiddenElement.Clear(); } } #endif } void RestyleManager::ComputeStyleChangeFor(nsIFrame* aFrame, nsStyleChangeList* aChangeList, nsChangeHint aMinChange, RestyleTracker& aRestyleTracker, bool aRestyleDescendants) { PROFILER_LABEL("CSS", "ComputeStyleChangeFor"); nsIContent *content = aFrame->GetContent(); if (aMinChange) { aChangeList->AppendChange(aFrame, content, aMinChange); } nsIFrame* frame = aFrame; NS_ASSERTION(!frame->GetPrevContinuation(), "must start with the first in flow"); // We need to handle aFrame and all of its continuations and special // siblings and their continuations. ReResolveStyleContext loops over // the continuations, and also loops over the similar-type sequences // in block-in-inline splits (i.e., either all the blocks or all the // inlines), so here we only have to advance one step to the other set // of special siblings (i.e., switch from blocks to inlines, or // vice-versa). FramePropertyTable* propTable = mPresContext->PropertyTable(); TreeMatchContext treeMatchContext(true, nsRuleWalker::eRelevantLinkUnvisited, mPresContext->Document()); nsIContent *parent = content ? content->GetParent() : nullptr; Element *parentElement = parent && parent->IsElement() ? parent->AsElement() : nullptr; treeMatchContext.InitAncestors(parentElement); nsTArray visibleKidsOfHiddenElement; for (int ibSet = 0; ibSet < 2; ++ibSet) { // loop over the two sets (blocks, inlines) of special siblings ElementRestyler restyler(mPresContext, frame, aChangeList, aMinChange, aRestyleTracker, treeMatchContext, visibleKidsOfHiddenElement); restyler.Restyle(aRestyleDescendants ? eRestyle_Subtree : eRestyle_Self); if (restyler.HintsHandledForFrame() & nsChangeHint_ReconstructFrame) { // If it's going to cause a framechange, then don't bother // with the continuations or special siblings since they'll be // clobbered by the frame reconstruct anyway. NS_ASSERTION(!frame->GetPrevContinuation(), "continuing frame had more severe impact than first-in-flow"); return; } // Might we have special siblings? if (!(frame->GetStateBits() & NS_FRAME_IS_SPECIAL)) { // nothing more to do here return; } frame = static_cast (propTable->Get(frame, nsIFrame::IBSplitSpecialSibling())); if (!frame) { return; } } } } // namespace mozilla