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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 is the root of the frame tree, which contains
* the document's scrollbars and contains fixed-positioned elements
#ifndef mozilla_ViewportFrame_h
#define mozilla_ViewportFrame_h
#include "mozilla/Attributes.h"
#include "nsContainerFrame.h"
class nsPresContext;
namespace mozilla {
class nsDisplayWrapList;
class ServoRestyleState;
* ViewportFrame is the parent of a single child - the doc root frame or a
* scroll frame containing the doc root frame. ViewportFrame stores this child
* in its primary child list.
class ViewportFrame : public nsContainerFrame {
explicit ViewportFrame(ComputedStyle* aStyle, nsPresContext* aPresContext)
: ViewportFrame(aStyle, aPresContext, kClassID) {}
virtual ~ViewportFrame() = default; // useful for debugging
void Init(nsIContent* aContent, nsContainerFrame* aParent,
nsIFrame* aPrevInFlow) override;
#ifdef DEBUG
void AppendFrames(ChildListID aListID, nsFrameList&& aFrameList) override;
void InsertFrames(ChildListID aListID, nsIFrame* aPrevFrame,
const nsLineList::iterator* aPrevFrameLine,
nsFrameList&& aFrameList) override;
void RemoveFrame(DestroyContext&, ChildListID, nsIFrame*) override;
void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) override;
nsDisplayWrapList* BuildDisplayListForTopLayer(nsDisplayListBuilder* aBuilder,
bool* aIsOpaque = nullptr);
nscoord GetMinISize(gfxContext* aRenderingContext) override;
nscoord GetPrefISize(gfxContext* aRenderingContext) override;
void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override;
bool ComputeCustomOverflow(mozilla::OverflowAreas&) override { return false; }
* Adjust aReflowInput to account for scrollbars and pres shell
* GetVisualViewportSizeSet and
* GetContentDocumentFixedPositionMargins adjustments.
* @return the rect to use as containing block rect
nsRect AdjustReflowInputAsContainingBlock(ReflowInput* aReflowInput) const;
* Update our style (and recursively the styles of any anonymous boxes we
* might own)
void UpdateStyle(ServoRestyleState& aStyleSet);
* Return our single anonymous box child.
void AppendDirectlyOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult) override;
// Returns adjusted viewport size to reflect the positions that position:fixed
// elements are attached.
nsSize AdjustViewportSizeForFixedPosition(const nsRect& aViewportRect) const;
virtual nsresult GetFrameName(nsAString& aResult) const override;
ViewportFrame(ComputedStyle* aStyle, nsPresContext* aPresContext, ClassID aID)
: nsContainerFrame(aStyle, aPresContext, aID), mView(nullptr) {}
* Calculate how much room is available for fixed frames. That means
* determining if the viewport is scrollable and whether the vertical and/or
* horizontal scrollbars are visible. Adjust the computed isize/bsize and
* available isize for aReflowInput accordingly.
* @return the current scroll position, or (0,0) if not scrollable.
nsPoint AdjustReflowInputForScrollbars(ReflowInput* aReflowInput) const;
nsView* GetViewInternal() const override { return mView; }
void SetViewInternal(nsView* aView) override { mView = aView; }
mozilla::FrameChildListID GetAbsoluteListID() const override {
return FrameChildListID::Fixed;
nsView* mView;
} // namespace mozilla
#endif // mozilla_ViewportFrame_h