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Diffstat (limited to 'layout/generic/nsGfxScrollFrame.h')
| -rw-r--r-- | layout/generic/nsGfxScrollFrame.h | 1090 |
1 files changed, 1090 insertions, 0 deletions
diff --git a/layout/generic/nsGfxScrollFrame.h b/layout/generic/nsGfxScrollFrame.h new file mode 100644 index 0000000000..e05a2a077b --- /dev/null +++ b/layout/generic/nsGfxScrollFrame.h @@ -0,0 +1,1090 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* 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/. */ + +/* rendering object to wrap rendering objects that should be scrollable */ + +#ifndef nsGfxScrollFrame_h___ +#define nsGfxScrollFrame_h___ + +#include "mozilla/Attributes.h" +#include "nsContainerFrame.h" +#include "nsIAnonymousContentCreator.h" +#include "nsIScrollableFrame.h" +#include "nsIScrollbarMediator.h" +#include "nsIStatefulFrame.h" +#include "nsThreadUtils.h" +#include "nsIReflowCallback.h" +#include "nsQueryFrame.h" +#include "nsExpirationTracker.h" +#include "TextOverflow.h" +#include "ScrollVelocityQueue.h" +#include "mozilla/ScrollTypes.h" +#include "mozilla/PresState.h" +#include "mozilla/layout/ScrollAnchorContainer.h" +#include "mozilla/TypedEnumBits.h" + +class nsPresContext; +class nsIContent; +class nsAtom; +class nsIScrollPositionListener; +class AutoContainsBlendModeCapturer; + +namespace mozilla { +class PresShell; +enum class StyleScrollbarWidth : uint8_t; +struct ScrollReflowInput; +struct StyleScrollSnapAlign; +namespace layers { +class Layer; +class WebRenderLayerManager; +} // namespace layers +namespace layout { +class ScrollbarActivity; +} // namespace layout + +} // namespace mozilla + +/** + * The scroll frame creates and manages the scrolling view + * + * It only supports having a single child frame that typically is an area + * frame, but doesn't have to be. The child frame must have a view, though + * + * Scroll frames don't support incremental changes, i.e. you can't replace + * or remove the scrolled frame + */ +class nsHTMLScrollFrame : public nsContainerFrame, + public nsIScrollableFrame, + public nsIAnonymousContentCreator, + public nsIReflowCallback, + public nsIStatefulFrame { + public: + using Sides = nsIFrame::Sides; + using ScrollbarActivity = mozilla::layout::ScrollbarActivity; + using ScrollSnapFlags = mozilla::ScrollSnapFlags; + using ScrollTriggeredByScript = mozilla::ScrollTriggeredByScript; + using ScrollSnapTargetIds = mozilla::ScrollSnapTargetIds; + using FrameMetrics = mozilla::layers::FrameMetrics; + using ScrollableLayerGuid = mozilla::layers::ScrollableLayerGuid; + using ScrollSnapInfo = mozilla::ScrollSnapInfo; + using WebRenderLayerManager = mozilla::layers::WebRenderLayerManager; + using APZScrollAnimationType = mozilla::APZScrollAnimationType; + using ScrollDirections = mozilla::layers::ScrollDirections; + using ScrollDirection = mozilla::layers::ScrollDirection; + using Element = mozilla::dom::Element; + using SnapTargetSet = nsTHashSet<RefPtr<nsIContent>>; + using InScrollingGesture = nsIScrollableFrame::InScrollingGesture; + + using CSSIntPoint = mozilla::CSSIntPoint; + using CSSPoint = mozilla::CSSPoint; + using ScrollReflowInput = mozilla::ScrollReflowInput; + using ScrollAnchorContainer = mozilla::layout::ScrollAnchorContainer; + friend nsHTMLScrollFrame* NS_NewHTMLScrollFrame( + mozilla::PresShell* aPresShell, ComputedStyle* aStyle, bool aIsRoot); + friend class mozilla::layout::ScrollAnchorContainer; + + NS_DECL_QUERYFRAME + NS_DECL_FRAMEARENA_HELPERS(nsHTMLScrollFrame) + + void BuildDisplayList(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists) override; + + bool TryLayout(ScrollReflowInput& aState, ReflowOutput* aKidMetrics, + bool aAssumeHScroll, bool aAssumeVScroll, bool aForce); + + // Return true if ReflowScrolledFrame is going to do something different based + // on the presence of a horizontal scrollbar in a horizontal writing mode or a + // vertical scrollbar in a vertical writing mode. + bool ScrolledContentDependsOnBSize(const ScrollReflowInput& aState) const; + + void ReflowScrolledFrame(ScrollReflowInput& aState, bool aAssumeHScroll, + bool aAssumeVScroll, ReflowOutput* aMetrics); + void ReflowContents(ScrollReflowInput& aState, + const ReflowOutput& aDesiredSize); + void PlaceScrollArea(ScrollReflowInput& aState, + const nsPoint& aScrollPosition); + + // Return the sum of inline-size of the scrollbar gutters (if any) at the + // inline-start and inline-end edges of the scroll frame (for a potential + // scrollbar that scrolls in the block axis). + nscoord IntrinsicScrollbarGutterSizeAtInlineEdges(); + + // Compute stable scrollbar-gutter from scrollbar-width and scrollbar-gutter + // properties. + // + // Note: this method doesn't consider overflow property and the space created + // by the actual scrollbars. That is, if scrollbar-gutter is 'auto', this + // method just returns empty result. + nsMargin ComputeStableScrollbarGutter( + const mozilla::StyleScrollbarWidth& aStyleScrollbarWidth, + const mozilla::StyleScrollbarGutter& aStyleScrollbarGutter) const; + + bool GetBorderRadii(const nsSize& aFrameSize, const nsSize& aBorderArea, + Sides aSkipSides, nscoord aRadii[8]) const final; + + nscoord GetMinISize(gfxContext* aRenderingContext) override; + nscoord GetPrefISize(gfxContext* aRenderingContext) override; + + void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize, + const ReflowInput& aReflowInput, + nsReflowStatus& aStatus) override; + void DidReflow(nsPresContext* aPresContext, + const ReflowInput* aReflowInput) override; + + bool ComputeCustomOverflow(mozilla::OverflowAreas& aOverflowAreas) final; + + BaselineSharingGroup GetDefaultBaselineSharingGroup() const override; + nscoord SynthesizeFallbackBaseline( + mozilla::WritingMode aWM, + BaselineSharingGroup aBaselineGroup) const override; + Maybe<nscoord> GetNaturalBaselineBOffset( + mozilla::WritingMode aWM, BaselineSharingGroup aBaselineGroup, + BaselineExportContext aExportContext) const override; + + // Recomputes the scrollable overflow area we store in the helper to take + // children that are affected by perpsective set on the outer frame and scroll + // at different rates. + void AdjustForPerspective(nsRect& aScrollableOverflow); + + // Called to set the child frames. We typically have three: the scroll area, + // the vertical scrollbar, and the horizontal scrollbar. + void SetInitialChildList(ChildListID aListID, + nsFrameList&& aChildList) override; + void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) final; + void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame, + const nsLineList::iterator* aPrevFrameLine, + nsFrameList&& aFrameList) final; + void RemoveFrame(DestroyContext&, ChildListID, nsIFrame*) final; + + void DidSetComputedStyle(ComputedStyle* aOldComputedStyle) final; + + void Destroy(DestroyContext&) override; + + nsIScrollableFrame* GetScrollTargetFrame() const final { + return const_cast<nsHTMLScrollFrame*>(this); + } + + nsContainerFrame* GetContentInsertionFrame() override { + return GetScrolledFrame()->GetContentInsertionFrame(); + } + + nsPoint GetPositionOfChildIgnoringScrolling(const nsIFrame* aChild) final { + nsPoint pt = aChild->GetPosition(); + if (aChild == GetScrolledFrame()) { + pt += GetScrollPosition(); + } + return pt; + } + + // nsIAnonymousContentCreator + nsresult CreateAnonymousContent(nsTArray<ContentInfo>&) final; + void AppendAnonymousContentTo(nsTArray<nsIContent*>&, uint32_t aFilter) final; + + // nsIScrollableFrame + nsIFrame* GetScrolledFrame() const final { return mScrolledFrame; } + mozilla::ScrollStyles GetScrollStyles() const final; + bool IsForTextControlWithNoScrollbars() const final; + bool HasAllNeededScrollbars() const final { + return GetCurrentAnonymousContent().contains(GetNeededAnonymousContent()); + } + + mozilla::layers::OverscrollBehaviorInfo GetOverscrollBehaviorInfo() + const final; + ScrollDirections GetAvailableScrollingDirectionsForUserInputEvents() + const final; + ScrollDirections GetScrollbarVisibility() const final { + ScrollDirections result; + if (mHasHorizontalScrollbar) { + result += ScrollDirection::eHorizontal; + } + if (mHasVerticalScrollbar) { + result += ScrollDirection::eVertical; + } + return result; + } + nsMargin GetActualScrollbarSizes( + nsIScrollableFrame::ScrollbarSizesOptions aOptions = + nsIScrollableFrame::ScrollbarSizesOptions::NONE) const final; + nsMargin GetDesiredScrollbarSizes() const final; + static nscoord GetNonOverlayScrollbarSize(const nsPresContext*, + mozilla::StyleScrollbarWidth); + nsSize GetLayoutSize() const final { + if (mIsUsingMinimumScaleSize) { + return mICBSize; + } + return mScrollPort.Size(); + } + nsRect GetScrolledRect() const final; + nsRect GetScrollPortRect() const final { return mScrollPort; } + nsPoint GetScrollPosition() const final { + return mScrollPort.TopLeft() - mScrolledFrame->GetPosition(); + } + nsPoint GetLogicalScrollPosition() const final { + nsPoint pt; + pt.x = IsPhysicalLTR() + ? mScrollPort.x - mScrolledFrame->GetPosition().x + : mScrollPort.XMost() - mScrolledFrame->GetRect().XMost(); + pt.y = mScrollPort.y - mScrolledFrame->GetPosition().y; + return pt; + } + + nsRect GetScrollRange() const final { return GetLayoutScrollRange(); } + nsSize GetVisualViewportSize() const final; + nsPoint GetVisualViewportOffset() const final; + bool SetVisualViewportOffset(const nsPoint& aOffset, bool aRepaint) final; + nsRect GetVisualScrollRange() const final; + nsRect GetScrollRangeForUserInputEvents() const final; + nsSize GetLineScrollAmount() const final; + nsSize GetPageScrollAmount() const final; + nsMargin GetScrollPadding() const final; + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void ScrollTo(nsPoint aScrollPosition, ScrollMode aMode, + const nsRect* aRange = nullptr, + ScrollSnapFlags aSnapFlags = ScrollSnapFlags::Disabled, + ScrollTriggeredByScript aTriggeredByScript = + ScrollTriggeredByScript::No) final { + return ScrollToInternal(aScrollPosition, aMode, ScrollOrigin::Other, aRange, + aSnapFlags, aTriggeredByScript); + } + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void ScrollToCSSPixels(const CSSIntPoint& aScrollPosition, + ScrollMode aMode = ScrollMode::Instant) final; + void ScrollToCSSPixelsForApz(const mozilla::CSSPoint& aScrollPosition, + ScrollSnapTargetIds&& aLastSnapTargetIds) final; + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + CSSIntPoint GetRoundedScrollPositionCSSPixels() final; + + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void ScrollBy(nsIntPoint aDelta, mozilla::ScrollUnit aUnit, ScrollMode aMode, + nsIntPoint* aOverflow, + ScrollOrigin aOrigin = ScrollOrigin::NotSpecified, + nsIScrollableFrame::ScrollMomentum aMomentum = + nsIScrollableFrame::NOT_MOMENTUM, + ScrollSnapFlags aSnapFlags = ScrollSnapFlags::Disabled) final; + void ScrollByCSSPixels(const CSSIntPoint& aDelta, + ScrollMode aMode = ScrollMode::Instant) final { + return ScrollByCSSPixelsInternal(aDelta, aMode); + } + void ScrollByCSSPixelsInternal( + const CSSIntPoint& aDelta, ScrollMode aMode = ScrollMode::Instant, + // This ScrollByCSSPixels is mainly used for Element.scrollBy and + // Window.scrollBy. An exception is the transmogrification of + // ScrollToCSSPixels. + ScrollSnapFlags aSnapFlags = ScrollSnapFlags::IntendedDirection | + ScrollSnapFlags::IntendedEndPosition); + + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void ScrollToRestoredPosition() final; + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void CurPosAttributeChanged(nsIContent* aChild) final { + return CurPosAttributeChangedInternal(aChild); + } + NS_IMETHOD PostScrolledAreaEventForCurrentArea() final { + PostScrolledAreaEvent(); + return NS_OK; + } + bool IsScrollingActive() const final; + bool IsMaybeAsynchronouslyScrolled() const final { + // If this is true, then we'll build an ASR, and that's what we want + // to know I think. + return mWillBuildScrollableLayer; + } + + bool DidHistoryRestore() const final { return mDidHistoryRestore; } + void ClearDidHistoryRestore() final { mDidHistoryRestore = false; } + void MarkEverScrolled() final; + bool IsRectNearlyVisible(const nsRect& aRect) const final; + nsRect ExpandRectToNearlyVisible(const nsRect& aRect) const final; + ScrollOrigin LastScrollOrigin() const final { return mLastScrollOrigin; } + using AnimationState = nsIScrollableFrame::AnimationState; + mozilla::EnumSet<AnimationState> ScrollAnimationState() const final; + mozilla::MainThreadScrollGeneration CurrentScrollGeneration() const final { + return mScrollGeneration; + } + mozilla::APZScrollGeneration ScrollGenerationOnApz() const final { + return mScrollGenerationOnApz; + } + nsPoint LastScrollDestination() final { return mDestination; } + nsTArray<mozilla::ScrollPositionUpdate> GetScrollUpdates() const final; + bool HasScrollUpdates() const final { return !mScrollUpdates.IsEmpty(); } + void ResetScrollInfoIfNeeded( + const mozilla::MainThreadScrollGeneration& aGeneration, + const mozilla::APZScrollGeneration& aGenerationOnApz, + mozilla::APZScrollAnimationType aAPZScrollAnimationType, + InScrollingGesture aInScrollingGesture) final; + bool WantAsyncScroll() const final; + mozilla::Maybe<mozilla::layers::ScrollMetadata> ComputeScrollMetadata( + mozilla::layers::WebRenderLayerManager* aLayerManager, + const nsIFrame* aItemFrame, + const nsPoint& aOffsetToReferenceFrame) const final; + void MarkScrollbarsDirtyForReflow() const final; + void InvalidateScrollbars() const final; + + /** + * @note This method might destroy the frame, pres shell and other objects. + * Update scrollbar curpos attributes to reflect current scroll position + */ + void UpdateScrollbarPosition() final; + bool DecideScrollableLayer(nsDisplayListBuilder* aBuilder, + nsRect* aVisibleRect, nsRect* aDirtyRect, + bool aSetBase) final { + return DecideScrollableLayer(aBuilder, aVisibleRect, aDirtyRect, aSetBase, + nullptr); + } + void NotifyApzTransaction() final; + void NotifyApproximateFrameVisibilityUpdate(bool aIgnoreDisplayPort) final; + bool GetDisplayPortAtLastApproximateFrameVisibilityUpdate( + nsRect* aDisplayPort) final; + void TriggerDisplayPortExpiration() final; + + // nsIStatefulFrame + mozilla::UniquePtr<mozilla::PresState> SaveState() final; + NS_IMETHOD RestoreState(mozilla::PresState* aState) final; + + // nsIScrollbarMediator + void ScrollByPage( + nsScrollbarFrame* aScrollbar, int32_t aDirection, + ScrollSnapFlags aSnapFlags = ScrollSnapFlags::Disabled) final; + void ScrollByWhole( + nsScrollbarFrame* aScrollbar, int32_t aDirection, + ScrollSnapFlags aSnapFlags = ScrollSnapFlags::Disabled) final; + void ScrollByLine(nsScrollbarFrame* aScrollbar, int32_t aDirection, + ScrollSnapFlags = ScrollSnapFlags::Disabled) final; + void ScrollByUnit(nsScrollbarFrame* aScrollbar, ScrollMode aMode, + int32_t aDirection, mozilla::ScrollUnit aUnit, + ScrollSnapFlags = ScrollSnapFlags::Disabled) final; + void RepeatButtonScroll(nsScrollbarFrame* aScrollbar) final; + void ThumbMoved(nsScrollbarFrame* aScrollbar, nscoord aOldPos, + nscoord aNewPos) final; + void ScrollbarReleased(nsScrollbarFrame* aScrollbar) final; + void VisibilityChanged(bool aVisible) final {} + nsScrollbarFrame* GetScrollbarBox(bool aVertical) final { + return aVertical ? mVScrollbarBox : mHScrollbarBox; + } + + void ScrollbarActivityStarted() const final; + void ScrollbarActivityStopped() const final; + + bool IsScrollbarOnRight() const final; + + bool ShouldSuppressScrollbarRepaints() const final { + return mSuppressScrollbarRepaints; + } + void SetTransformingByAPZ(bool aTransforming) final; + bool IsTransformingByAPZ() const final { return mTransformingByAPZ; } + void SetScrollableByAPZ(bool aScrollable) final; + void SetZoomableByAPZ(bool aZoomable) final; + void SetHasOutOfFlowContentInsideFilter() final; + ScrollSnapInfo GetScrollSnapInfo() final; + + void TryResnap() final; + void PostPendingResnapIfNeeded(const nsIFrame* aFrame) final; + void PostPendingResnap() final; + using PhysicalScrollSnapAlign = nsIScrollableFrame::PhysicalScrollSnapAlign; + PhysicalScrollSnapAlign GetScrollSnapAlignFor( + const nsIFrame* aFrame) const final; + + bool DragScroll(mozilla::WidgetEvent* aEvent) final; + + void AsyncScrollbarDragInitiated( + uint64_t aDragBlockId, mozilla::layers::ScrollDirection aDirection) final; + + void AsyncScrollbarDragRejected() final; + + bool IsRootScrollFrameOfDocument() const final { return mIsRoot; } + + Maybe<uint32_t> IsFirstScrollableFrameSequenceNumber() const final { + return mIsFirstScrollableFrameSequenceNumber; + } + + void SetIsFirstScrollableFrameSequenceNumber(Maybe<uint32_t> aValue) final { + mIsFirstScrollableFrameSequenceNumber = aValue; + } + + const ScrollAnchorContainer* Anchor() const final { return &mAnchor; } + ScrollAnchorContainer* Anchor() final { return &mAnchor; } + + // Return the scrolled frame. + void AppendDirectlyOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult) final { + aResult.AppendElement(OwnedAnonBox(GetScrolledFrame())); + } + + bool SmoothScrollVisual( + const nsPoint& aVisualViewportOffset, + mozilla::layers::FrameMetrics::ScrollOffsetUpdateType aUpdateType) final; + + bool IsSmoothScroll(mozilla::dom::ScrollBehavior aBehavior) const final; + +#ifdef DEBUG_FRAME_DUMP + nsresult GetFrameName(nsAString& aResult) const override; +#endif + +#ifdef ACCESSIBILITY + mozilla::a11y::AccType AccessibleType() override; +#endif + + protected: + nsHTMLScrollFrame(ComputedStyle* aStyle, nsPresContext* aPresContext, + bool aIsRoot) + : nsHTMLScrollFrame(aStyle, aPresContext, kClassID, aIsRoot) {} + nsHTMLScrollFrame(ComputedStyle* aStyle, nsPresContext* aPresContext, + nsIFrame::ClassID aID, bool aIsRoot); + ~nsHTMLScrollFrame(); + void SetSuppressScrollbarUpdate(bool aSuppress) { + mSuppressScrollbarUpdate = aSuppress; + } + bool GuessHScrollbarNeeded(const ScrollReflowInput& aState); + bool GuessVScrollbarNeeded(const ScrollReflowInput& aState); + + bool IsScrollbarUpdateSuppressed() const { return mSuppressScrollbarUpdate; } + + // Return whether we're in an "initial" reflow. Some reflows with + // NS_FRAME_FIRST_REFLOW set are NOT "initial" as far as we're concerned. + bool InInitialReflow() const; + + /** + * Override this to return false if computed bsize/min-bsize/max-bsize + * should NOT be propagated to child content. + * nsListControlFrame uses this. + */ + virtual bool ShouldPropagateComputedBSizeToScrolledContent() const { + return true; + } + + private: + class AsyncScroll; + class AsyncSmoothMSDScroll; + + enum class AnonymousContentType { + VerticalScrollbar, + HorizontalScrollbar, + Resizer, + }; + mozilla::EnumSet<AnonymousContentType> GetNeededAnonymousContent() const; + mozilla::EnumSet<AnonymousContentType> GetCurrentAnonymousContent() const; + + // If a child frame was added or removed on the scrollframe, + // reload our child frame list. + // We need this if a scrollbar frame is recreated. + void ReloadChildFrames(); + + public: + enum class OverflowState : uint32_t { + None = 0, + Vertical = (1 << 0), + Horizontal = (1 << 1), + }; + + protected: + OverflowState GetOverflowState() const; + + MOZ_CAN_RUN_SCRIPT nsresult FireScrollPortEvent(); + void PostScrollEndEvent(); + MOZ_CAN_RUN_SCRIPT void FireScrollEndEvent(); + void PostOverflowEvent(); + + // Add display items for the top-layer (which includes things like + // the fullscreen element, its backdrop, and text selection carets) + // to |aLists|. + // This is a no-op for scroll frames other than the viewport's + // root scroll frame. + // This should be called with an nsDisplayListSet that will be + // wrapped in the async zoom container, if we're building one. + // It should not be called with an ASR setter on the stack, as the + // top-layer items handle setting up their own ASRs. + void MaybeCreateTopLayerAndWrapRootItems( + nsDisplayListBuilder*, mozilla::nsDisplayListCollection&, + bool aCreateAsyncZoom, + AutoContainsBlendModeCapturer* aAsyncZoomBlendCapture, + const nsRect& aAsyncZoomClipRect, nscoord* aRadii); + + void AppendScrollPartsTo(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists, bool aCreateLayer, + bool aPositioned); + + // nsIReflowCallback + bool ReflowFinished() final; + void ReflowCallbackCanceled() final; + + /** + * @note This method might destroy the frame, pres shell and other objects. + * Called when the 'curpos' attribute on one of the scrollbars changes. + */ + void CurPosAttributeChangedInternal(nsIContent*, bool aDoScroll = true); + + void PostScrollEvent(bool aDelayed = false); + MOZ_CAN_RUN_SCRIPT void FireScrollEvent(); + void PostScrolledAreaEvent(); + MOZ_CAN_RUN_SCRIPT void FireScrolledAreaEvent(); + + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void FinishReflowForScrollbar(Element* aElement, nscoord aMinXY, + nscoord aMaxXY, nscoord aCurPosXY, + nscoord aPageIncrement, nscoord aIncrement); + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void SetScrollbarEnabled(Element* aElement, nscoord aMaxPos); + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void SetCoordAttribute(Element* aElement, nsAtom* aAtom, nscoord aSize); + + nscoord GetCoordAttribute(nsIFrame* aFrame, nsAtom* aAtom, + nscoord aDefaultValue, nscoord* aRangeStart, + nscoord* aRangeLength); + + nsRect GetLayoutScrollRange() const; + // Get the scroll range assuming the viewport has size (aWidth, aHeight). + nsRect GetScrollRange(nscoord aWidth, nscoord aHeight) const; + + const nsRect& ScrollPort() const { return mScrollPort; } + void SetScrollPort(const nsRect& aNewScrollPort) { + if (!mScrollPort.IsEqualEdges(aNewScrollPort)) { + mMayScheduleScrollAnimations = true; + } + mScrollPort = aNewScrollPort; + } + + /** + * Return the 'optimal viewing region' as a rect suitable for use by + * scroll anchoring. This rect is in the same coordinate space as + * 'GetScrollPortRect', and accounts for 'scroll-padding' as defined by: + * + * https://drafts.csswg.org/css-scroll-snap-1/#optimal-viewing-region + */ + nsRect GetVisualOptimalViewingRect() const; + + /** + * For LTR frames, this is the same as GetVisualViewportOffset(). + * For RTL frames, we take the offset from the top right corner of the frame + * to the top right corner of the visual viewport. + */ + nsPoint GetLogicalVisualViewportOffset() const { + nsPoint pt = GetVisualViewportOffset(); + if (!IsPhysicalLTR()) { + pt.x += GetVisualViewportSize().width - mScrolledFrame->GetRect().width; + } + return pt; + } + void ScrollSnap() final { return ScrollSnap(ScrollMode::SmoothMsd); } + void ScrollSnap(ScrollMode aMode); + void ScrollSnap(const nsPoint& aDestination, + ScrollMode aMode = ScrollMode::SmoothMsd); + + bool HasPendingScrollRestoration() const { + return mRestorePos != nsPoint(-1, -1); + } + + bool IsProcessingScrollEvent() const { return mProcessingScrollEvent; } + + public: + static void AsyncScrollCallback(nsHTMLScrollFrame* aInstance, + mozilla::TimeStamp aTime); + static void AsyncSmoothMSDScrollCallback(nsHTMLScrollFrame* aInstance, + mozilla::TimeDuration aDeltaTime); + /** + * @note This method might destroy the frame, pres shell and other objects. + * aRange is the range of allowable scroll positions around the desired + * aScrollPosition. Null means only aScrollPosition is allowed. + * This is a closed-ended range --- aRange.XMost()/aRange.YMost() are allowed. + */ + void ScrollToInternal( + nsPoint aScrollPosition, ScrollMode aMode, + ScrollOrigin aOrigin = ScrollOrigin::NotSpecified, + const nsRect* aRange = nullptr, + ScrollSnapFlags aSnapFlags = ScrollSnapFlags::Disabled, + ScrollTriggeredByScript aTriggeredByScript = ScrollTriggeredByScript::No); + /** + * @note This method might destroy the frame, pres shell and other objects. + */ + void ScrollToImpl( + nsPoint aPt, const nsRect& aRange, + ScrollOrigin aOrigin = ScrollOrigin::NotSpecified, + ScrollTriggeredByScript aTriggeredByScript = ScrollTriggeredByScript::No); + void ScrollVisual(); + + enum class LoadingState { Loading, Stopped, Loaded }; + + LoadingState GetPageLoadingState(); + + /** + * GetSnapPointForDestination determines which point to snap to after + * scrolling. aStartPos gives the position before scrolling and aDestination + * gives the position after scrolling, with no snapping. Behaviour is + * dependent on the value of aUnit. + * Returns true if a suitable snap point could be found and aDestination has + * been updated to a valid snapping position. + */ + Maybe<mozilla::SnapDestination> GetSnapPointForDestination( + mozilla::ScrollUnit aUnit, ScrollSnapFlags aFlags, + const nsPoint& aStartPos, const nsPoint& aDestination); + + Maybe<mozilla::SnapDestination> GetSnapPointForResnap(); + bool NeedsResnap(); + + void SetLastSnapTargetIds(mozilla::UniquePtr<ScrollSnapTargetIds> aId); + void AddScrollPositionListener(nsIScrollPositionListener* aListener) final { + mListeners.AppendElement(aListener); + } + void RemoveScrollPositionListener( + nsIScrollPositionListener* aListener) final { + mListeners.RemoveElement(aListener); + } + + static void SetScrollbarVisibility(nsIFrame* aScrollbar, bool aVisible); + + /** + * GetUnsnappedScrolledRectInternal is designed to encapsulate deciding which + * directions of overflow should be reachable by scrolling and which + * should not. Callers should NOT depend on it having any particular + * behavior. + * + * Currently it allows scrolling down and to the right for + * nsHTMLScrollFrames with LTR directionality, and allows scrolling down and + * to the left for nsHTMLScrollFrames with RTL directionality. + */ + nsRect GetUnsnappedScrolledRectInternal(const nsRect& aScrolledOverflowArea, + const nsSize& aScrollPortSize) const; + + bool IsPhysicalLTR() const { return GetWritingMode().IsPhysicalLTR(); } + bool IsBidiLTR() const { return GetWritingMode().IsBidiLTR(); } + + private: + // NOTE: Use GetScrollStylesFromFrame() if you want to know `overflow` + // and `overflow-behavior` properties. + nsIFrame* GetFrameForStyle() const; + + // Compute all scroll snap related information and store eash snap target + // element in |mSnapTargets|. + ScrollSnapInfo ComputeScrollSnapInfo(); + + bool NeedsScrollSnap() const; + + // Returns the snapport size of this scroll container. + // https://drafts.csswg.org/css-scroll-snap/#scroll-snapport + nsSize GetSnapportSize() const; + + // Schedule the scroll-driven animations. + void ScheduleScrollAnimations(); + void TryScheduleScrollAnimations() { + if (!mMayScheduleScrollAnimations) { + return; + } + ScheduleScrollAnimations(); + mMayScheduleScrollAnimations = false; + } + + CSSPoint GetScrollPositionCSSPixels() const { + return CSSPoint::FromAppUnits(GetScrollPosition()); + } + + public: + void UpdateSticky(); + + void UpdatePrevScrolledRect(); + + // adjust the scrollbar rectangle aRect to account for any visible resizer. + // aHasResizer specifies if there is a content resizer, however this method + // will also check if a widget resizer is present as well. + void AdjustScrollbarRectForResizer( + nsIFrame* aFrame, nsPresContext* aPresContext, nsRect& aRect, + bool aHasResizer, mozilla::layers::ScrollDirection aDirection); + void LayoutScrollbars(ScrollReflowInput& aState, + const nsRect& aInsideBorderArea, + const nsRect& aOldScrollPort); + + void LayoutScrollbarPartAtRect(const ScrollReflowInput&, + ReflowInput& aKidReflowInput, const nsRect&); + + bool IsAlwaysActive() const; + void MarkRecentlyScrolled(); + void MarkNotRecentlyScrolled(); + nsExpirationState* GetExpirationState() { return &mActivityExpirationState; } + + bool UsesOverlayScrollbars() const; + bool IsLastSnappedTarget(const nsIFrame* aFrame) const; + + static bool ShouldActivateAllScrollFrames(); + nsRect RestrictToRootDisplayPort(const nsRect& aDisplayportBase); + bool DecideScrollableLayer(nsDisplayListBuilder* aBuilder, + nsRect* aVisibleRect, nsRect* aDirtyRect, + bool aSetBase, + bool* aDirtyRectHasBeenOverriden = nullptr); + bool AllowDisplayPortExpiration(); + void ResetDisplayPortExpiryTimer(); + + void ScheduleSyntheticMouseMove(); + static void ScrollActivityCallback(nsITimer* aTimer, void* anInstance); + + void HandleScrollbarStyleSwitching(); + + bool IsApzAnimationInProgress() const { + return mCurrentAPZScrollAnimationType != APZScrollAnimationType::No; + } + nsPoint LastScrollDestination() const { return mDestination; } + + bool IsLastScrollUpdateAnimating() const; + bool IsLastScrollUpdateTriggeredByScriptAnimating() const; + + // Update minimum-scale size. The minimum-scale size will be set/used only + // if there is overflow-x:hidden region. + void UpdateMinimumScaleSize(const nsRect& aScrollableOverflow, + const nsSize& aICBSize); + + // Return the scroll frame's "true outer size". + // This is GetSize(), except when we've been sized to reflect a virtual + // (layout) viewport in which case this returns the outer size used to size + // the physical (visual) viewport. + nsSize TrueOuterSize(nsDisplayListBuilder* aBuilder) const; + + already_AddRefed<Element> MakeScrollbar(mozilla::dom::NodeInfo* aNodeInfo, + bool aVertical, + mozilla::AnonymousContentKey& aKey); + + void AppendScrollUpdate(const mozilla::ScrollPositionUpdate& aUpdate); + + // owning references to the nsIAnonymousContentCreator-built content + nsCOMPtr<Element> mHScrollbarContent; + nsCOMPtr<Element> mVScrollbarContent; + nsCOMPtr<Element> mScrollCornerContent; + nsCOMPtr<Element> mResizerContent; + + class ScrollEvent; + class ScrollEndEvent; + class AsyncScrollPortEvent; + class ScrolledAreaEvent; + + RefPtr<ScrollEvent> mScrollEvent; + RefPtr<ScrollEndEvent> mScrollEndEvent; + nsRevocableEventPtr<AsyncScrollPortEvent> mAsyncScrollPortEvent; + nsRevocableEventPtr<ScrolledAreaEvent> mScrolledAreaEvent; + nsScrollbarFrame* mHScrollbarBox; + nsScrollbarFrame* mVScrollbarBox; + nsIFrame* mScrolledFrame; + nsIFrame* mScrollCornerBox; + nsIFrame* mResizerBox; + const nsIFrame* mReferenceFrameDuringPainting; + RefPtr<AsyncScroll> mAsyncScroll; + RefPtr<AsyncSmoothMSDScroll> mAsyncSmoothMSDScroll; + RefPtr<ScrollbarActivity> mScrollbarActivity; + nsTArray<nsIScrollPositionListener*> mListeners; + ScrollOrigin mLastScrollOrigin; + Maybe<nsPoint> mApzSmoothScrollDestination; + mozilla::MainThreadScrollGeneration mScrollGeneration; + mozilla::APZScrollGeneration mScrollGenerationOnApz; + + nsTArray<mozilla::ScrollPositionUpdate> mScrollUpdates; + + nsSize mMinimumScaleSize; + + // Stores the ICB size for the root document if this frame is using the + // minimum scale size for |mScrollPort|. + nsSize mICBSize; + + // Where we're currently scrolling to, if we're scrolling asynchronously. + // If we're not in the middle of an asynchronous scroll then this is + // just the current scroll position. ScrollBy will choose its + // destination based on this value. + nsPoint mDestination; + + // A goal position to try to scroll to as content loads. As long as mLastPos + // matches the current logical scroll position, we try to scroll to + // mRestorePos after every reflow --- because after each time content is + // loaded/added to the scrollable element, there will be a reflow. + // Note that for frames where layout and visual viewport aren't one and the + // same thing, this scroll position will be the logical scroll position of + // the *visual* viewport, as its position will be more relevant to the user. + nsPoint mRestorePos; + // The last logical position we scrolled to while trying to restore + // mRestorePos, or 0,0 when this is a new frame. Set to -1,-1 once we've + // scrolled for any reason other than trying to restore mRestorePos. + // Just as with mRestorePos, this position will be the logical position of + // the *visual* viewport where available. + nsPoint mLastPos; + + // The latest scroll position we've sent or received from APZ. This + // represents the main thread's best knowledge of the APZ scroll position, + // and is used to calculate relative scroll offset updates. + nsPoint mApzScrollPos; + + nsExpirationState mActivityExpirationState; + + nsCOMPtr<nsITimer> mScrollActivityTimer; + + // The scroll position where we last updated frame visibility. + nsPoint mLastUpdateFramesPos; + nsRect mDisplayPortAtLastFrameUpdate; + + nsRect mPrevScrolledRect; + + ScrollableLayerGuid::ViewID mScrollParentID; + + // Timer to remove the displayport some time after scrolling has stopped + nsCOMPtr<nsITimer> mDisplayPortExpiryTimer; + + ScrollAnchorContainer mAnchor; + + // We keep holding a strong reference for each snap target element until the + // next snapping happens so that it avoids using the same nsIContent* pointer + // for newly created contents in this scroll container. Otherwise we will try + // to match different nsIContent(s) generated at the same address during + // re-snapping. + SnapTargetSet mSnapTargets; + + // Representing there's an APZ animation is in progress and what caused the + // animation. Note that this is only set when repainted via APZ, which means + // that there may be a request for an APZ animation in flight for example, + // while this is still `No`. In order to answer "is an APZ animation in the + // process of starting or in progress" you need to check mScrollUpdates, + // mApzAnimationRequested, and this type. + APZScrollAnimationType mCurrentAPZScrollAnimationType; + + // The paint sequence number if the scroll frame is the first scrollable frame + // encountered. + Maybe<uint32_t> mIsFirstScrollableFrameSequenceNumber; + + // Representing whether the APZC corresponding to this frame is now in the + // middle of handling a gesture (e.g. a pan gesture). + InScrollingGesture mInScrollingGesture : 1; + + bool mAllowScrollOriginDowngrade : 1; + bool mHadDisplayPortAtLastFrameUpdate : 1; + + // True if the most recent reflow of the scroll container frame has + // the vertical scrollbar shown. + bool mHasVerticalScrollbar : 1; + // True if the most recent reflow of the scroll container frame has the + // horizontal scrollbar shown. + bool mHasHorizontalScrollbar : 1; + + // If mHas(Vertical|Horizontal)Scrollbar is true then + // mOnlyNeed(V|H)ScrollbarToScrollVVInsideLV indicates if the only reason we + // need that scrollbar is to scroll the visual viewport inside the layout + // viewport. These scrollbars are special in that even if they are layout + // scrollbars they do not take up any layout space. + bool mOnlyNeedVScrollbarToScrollVVInsideLV : 1; + bool mOnlyNeedHScrollbarToScrollVVInsideLV : 1; + bool mFrameIsUpdatingScrollbar : 1; + bool mDidHistoryRestore : 1; + // Is this the scrollframe for the document's viewport? + bool mIsRoot : 1; + // If true, don't try to layout the scrollbars in Reflow(). This can be + // useful if multiple passes are involved, because we don't want to place the + // scrollbars at the wrong size. + bool mSuppressScrollbarUpdate : 1; + // If true, we skipped a scrollbar layout due to mSuppressScrollbarUpdate + // being set at some point. That means we should lay out scrollbars even if + // it might not strictly be needed next time mSuppressScrollbarUpdate is + // false. + bool mSkippedScrollbarLayout : 1; + + bool mHadNonInitialReflow : 1; + // Initially true; first call to ReflowFinished() sets it to false. + bool mFirstReflow : 1; + // State used only by PostScrollEvents so we know + // which overflow states have changed. + bool mHorizontalOverflow : 1; + bool mVerticalOverflow : 1; + bool mPostedReflowCallback : 1; + bool mMayHaveDirtyFixedChildren : 1; + // If true, need to actually update our scrollbar attributes in the + // reflow callback. + bool mUpdateScrollbarAttributes : 1; + // If true, we should be prepared to scroll using this scrollframe + // by placing descendant content into its own layer(s) + bool mHasBeenScrolledRecently : 1; + + // If true, the scroll frame should always be active because we always build + // a scrollable layer. Used for asynchronous scrolling. + bool mWillBuildScrollableLayer : 1; + + // If true, the scroll frame is an ancestor of other "active" scrolling + // frames, where "active" means has a non-minimal display port if + // ShouldActivateAllScrollFrames is true, or has a display port if + // ShouldActivateAllScrollFrames is false. And this means that we shouldn't + // expire the display port (if ShouldActivateAllScrollFrames is true then + // expiring a display port means making it minimal, otherwise it means + // removing the display port). If those descendant scrollframes have their + // display ports removed or made minimal, then we expire our display port. + bool mIsParentToActiveScrollFrames : 1; + + // True if this frame has been scrolled at least once + bool mHasBeenScrolled : 1; + + // True if the events synthesized by OSX to produce momentum scrolling should + // be ignored. Reset when the next real, non-synthesized scroll event occurs. + bool mIgnoreMomentumScroll : 1; + + // True if the APZ is in the process of async-transforming this scrollframe, + // (as best as we can tell on the main thread, anyway). + bool mTransformingByAPZ : 1; + + // True if APZ can scroll this frame asynchronously (i.e. it has an APZC + // set up for this frame and it's not a scrollinfo layer). + bool mScrollableByAPZ : 1; + + // True if the APZ is allowed to zoom this scrollframe. + bool mZoomableByAPZ : 1; + + // True if the scroll frame contains out-of-flow content and is inside + // a CSS filter. + bool mHasOutOfFlowContentInsideFilter : 1; + + // True if we don't want the scrollbar to repaint itself right now. + bool mSuppressScrollbarRepaints : 1; + + // True if we are using the minimum scale size instead of ICB for scroll port. + bool mIsUsingMinimumScaleSize : 1; + + // True if the minimum scale size has been changed since the last reflow. + bool mMinimumScaleSizeChanged : 1; + + // True if we're processing an scroll event. + bool mProcessingScrollEvent : 1; + + // This is true from the time a scroll animation is requested of APZ to the + // time that APZ responds with an up-to-date repaint request. More precisely, + // this is flipped to true if a repaint request is dispatched to APZ where + // the most recent scroll request is a smooth scroll, and it is cleared when + // mApzAnimationInProgress is updated. + bool mApzAnimationRequested : 1; + + // Similar to above mApzAnimationRequested but the request came from script, + // e.g., scrollBy(). + bool mApzAnimationTriggeredByScriptRequested : 1; + + // Whether we need to reclamp the visual viewport offset in ReflowFinished. + bool mReclampVVOffsetInReflowFinished : 1; + + // Whether we need to schedule the scroll-driven animations. + bool mMayScheduleScrollAnimations : 1; + +#ifdef MOZ_WIDGET_ANDROID + // True if this scrollable frame was vertically overflowed on the last reflow. + bool mHasVerticalOverflowForDynamicToolbar : 1; +#endif + + mozilla::layout::ScrollVelocityQueue mVelocityQueue; + + protected: + class AutoScrollbarRepaintSuppression; + friend class AutoScrollbarRepaintSuppression; + class AutoScrollbarRepaintSuppression { + public: + AutoScrollbarRepaintSuppression(nsHTMLScrollFrame* aFrame, + AutoWeakFrame& aWeakOuter, bool aSuppress) + : mFrame(aFrame), + mWeakOuter(aWeakOuter), + mOldSuppressValue(aFrame->mSuppressScrollbarRepaints) { + mFrame->mSuppressScrollbarRepaints = aSuppress; + } + + ~AutoScrollbarRepaintSuppression() { + if (mWeakOuter.IsAlive()) { + mFrame->mSuppressScrollbarRepaints = mOldSuppressValue; + } + } + + private: + nsHTMLScrollFrame* mFrame; + AutoWeakFrame& mWeakOuter; + bool mOldSuppressValue; + }; + + struct ScrollOperationParams { + ScrollOperationParams(const ScrollOperationParams&) = delete; + ScrollOperationParams(ScrollMode aMode, ScrollOrigin aOrigin) + : mMode(aMode), mOrigin(aOrigin) {} + ScrollOperationParams(ScrollMode aMode, ScrollOrigin aOrigin, + ScrollSnapTargetIds&& aSnapTargetIds) + : ScrollOperationParams(aMode, aOrigin) { + mTargetIds = std::move(aSnapTargetIds); + } + ScrollOperationParams(ScrollMode aMode, ScrollOrigin aOrigin, + ScrollSnapFlags aSnapFlags, + ScrollTriggeredByScript aTriggeredByScript) + : ScrollOperationParams(aMode, aOrigin) { + mSnapFlags = aSnapFlags; + mTriggeredByScript = aTriggeredByScript; + } + + ScrollMode mMode; + ScrollOrigin mOrigin; + ScrollSnapFlags mSnapFlags = ScrollSnapFlags::Disabled; + ScrollTriggeredByScript mTriggeredByScript = ScrollTriggeredByScript::No; + ScrollSnapTargetIds mTargetIds; + + bool IsInstant() const { return mMode == ScrollMode::Instant; } + bool IsSmoothMsd() const { return mMode == ScrollMode::SmoothMsd; } + bool IsSmooth() const { return mMode == ScrollMode::Smooth; } + bool IsScrollSnapDisabled() const { + return mSnapFlags == ScrollSnapFlags::Disabled; + } + }; + + /** + * @note This method might destroy the frame, pres shell and other objects. + * + * A caller can ask this ScrollToWithOrigin() function to perform snapping by + * passing in aParams.mSnapFlags != ScrollSnapFlags::Disabled. Alternatively, + * a caller may want to do its own snapping, in which case it should pass + * ScrollSnapFlags::Disabled and populate aParams.mTargetIds based on the + * result of the snapping. + */ + void ScrollToWithOrigin(nsPoint aScrollPosition, const nsRect* aRange, + ScrollOperationParams&& aParams); + + void CompleteAsyncScroll( + const nsPoint& aScrollPosition, const nsRect& aRange, + mozilla::UniquePtr<ScrollSnapTargetIds> aSnapTargetIds, + ScrollOrigin aOrigin = ScrollOrigin::NotSpecified); + + bool HasPerspective() const { return ChildrenHavePerspective(); } + bool HasBgAttachmentLocal() const; + mozilla::StyleDirection GetScrolledFrameDir() const; + + // Ask APZ to smooth scroll to |aDestination|. + // This method does not clamp the destination; callers should clamp it to + // either the layout or the visual scroll range (APZ will happily smooth + // scroll to either). + void ApzSmoothScrollTo( + const nsPoint& aDestination, ScrollMode, ScrollOrigin, + mozilla::ScrollTriggeredByScript, + mozilla::UniquePtr<ScrollSnapTargetIds> aSnapTargetIds); + + // Check whether APZ can scroll in the provided directions, keeping in mind + // that APZ currently cannot scroll along axes which are overflow:hidden. + bool CanApzScrollInTheseDirections( + mozilla::layers::ScrollDirections aDirections); + + // Removes any RefreshDriver observers we might have registered. + void RemoveObservers(); + + private: + // NOTE: On mobile this value might be factoring into overflow:hidden region + // in the case of the top level document. + nsRect mScrollPort; + mozilla::UniquePtr<ScrollSnapTargetIds> mLastSnapTargetIds; +}; + +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(nsHTMLScrollFrame::OverflowState) + +#endif /* nsGfxScrollFrame_h___ */ |