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/* -*- 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 */
/* rendering object that goes directly inside the document's scrollbars */
#ifndef nsCanvasFrame_h___
#define nsCanvasFrame_h___
#include "mozilla/Attributes.h"
#include "mozilla/EventForwards.h"
#include "nsContainerFrame.h"
#include "nsDisplayList.h"
#include "nsIAnonymousContentCreator.h"
#include "nsIPopupContainer.h"
#include "nsIScrollPositionListener.h"
class nsPresContext;
class gfxContext;
* Root frame class.
* The root frame is the parent frame for the document element's frame.
* It only supports having a single child frame which must be an area
* frame.
* @note nsCanvasFrame keeps overflow container continuations of its child
* frame in the main child list.
class nsCanvasFrame final : public nsContainerFrame,
public nsIScrollPositionListener,
public nsIAnonymousContentCreator,
public nsIPopupContainer {
using Element = mozilla::dom::Element;
explicit nsCanvasFrame(ComputedStyle* aStyle, nsPresContext* aPresContext)
: nsContainerFrame(aStyle, aPresContext, kClassID),
mAddedScrollPositionListener(false) {}
Element* GetDefaultTooltip() override;
void Destroy(DestroyContext&) override;
void SetInitialChildList(ChildListID aListID,
nsFrameList&& aChildList) override;
void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override;
void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine,
nsFrameList&& aFrameList) override;
#ifdef DEBUG
void RemoveFrame(DestroyContext&, ChildListID, nsIFrame*) override;
nscoord GetMinISize(gfxContext* aRenderingContext) override;
nscoord GetPrefISize(gfxContext* aRenderingContext) override;
void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override;
// nsIAnonymousContentCreator
nsresult CreateAnonymousContent(nsTArray<ContentInfo>& aElements) override;
void AppendAnonymousContentTo(nsTArray<nsIContent*>& aElements,
uint32_t aFilter) override;
Element* GetCustomContentContainer() const { return mCustomContentContainer; }
* Unhide the CustomContentContainer. This call only has an effect if
* mCustomContentContainer is non-null.
void ShowCustomContentContainer();
* Hide the CustomContentContainer. This call only has an effect if
* mCustomContentContainer is non-null.
void HideCustomContentContainer();
/** SetHasFocus tells the CanvasFrame to draw with focus ring
* @param aHasFocus true to show focus ring, false to hide it
NS_IMETHOD SetHasFocus(bool aHasFocus);
void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) override;
void PaintFocus(mozilla::gfx::DrawTarget* aRenderingContext, nsPoint aPt);
// nsIScrollPositionListener
void ScrollPositionWillChange(nscoord aX, nscoord aY) override;
void ScrollPositionDidChange(nscoord aX, nscoord aY) override {}
nsresult GetFrameName(nsAString& aResult) const override;
nsresult GetContentForEvent(const mozilla::WidgetEvent* aEvent,
nsIContent** aContent) override;
nsRect CanvasArea() const;
// Data members
bool mDoPaintFocus;
bool mAddedScrollPositionListener;
nsCOMPtr<Element> mCustomContentContainer;
nsCOMPtr<Element> mTooltipContent;
namespace mozilla {
* Override nsDisplayBackground methods so that we pass aBGClipRect to
* PaintBackground, covering the whole overflow area.
* We can also paint an "extra background color" behind the normal
* background.
class nsDisplayCanvasBackgroundColor final : public nsDisplaySolidColorBase {
nsDisplayCanvasBackgroundColor(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame)
: nsDisplaySolidColorBase(aBuilder, aFrame, NS_RGBA(0, 0, 0, 0)) {}
nsRect GetBounds(nsDisplayListBuilder* aBuilder, bool* aSnap) const override {
nsCanvasFrame* frame = static_cast<nsCanvasFrame*>(mFrame);
*aSnap = true;
return frame->CanvasArea() + ToReferenceFrame();
void HitTest(nsDisplayListBuilder* aBuilder, const nsRect& aRect,
HitTestState* aState, nsTArray<nsIFrame*>* aOutFrames) override {
// We need to override so we don't consider border-radius.
bool CreateWebRenderCommands(
mozilla::wr::DisplayListBuilder& aBuilder,
mozilla::wr::IpcResourceUpdateQueue& aResources,
const StackingContextHelper& aSc,
mozilla::layers::RenderRootStateManager* aManager,
nsDisplayListBuilder* aDisplayListBuilder) override;
void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override;
void SetExtraBackgroundColor(nscolor aColor) { mColor = aColor; }
void WriteDebugInfo(std::stringstream& aStream) override;
class nsDisplayCanvasBackgroundImage : public nsDisplayBackgroundImage {
explicit nsDisplayCanvasBackgroundImage(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame,
const InitData& aInitData)
: nsDisplayBackgroundImage(aBuilder, aFrame, aInitData) {}
void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override;
// We still need to paint a background color as well as an image for this
// item, so we can't support this yet.
bool SupportsOptimizingToImage() const override { return false; }
bool IsSingleFixedPositionImage(nsDisplayListBuilder* aBuilder,
const nsRect& aClipRect, gfxRect* aDestRect);
class nsDisplayCanvasThemedBackground : public nsDisplayThemedBackground {
nsDisplayCanvasThemedBackground(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame)
: nsDisplayThemedBackground(aBuilder, aFrame,
aFrame->GetRectRelativeToSelf() +
aBuilder->ToReferenceFrame(aFrame)) {
void Paint(nsDisplayListBuilder* aBuilder, gfxContext* aCtx) override;
} // namespace mozilla
#endif /* nsCanvasFrame_h___ */