gecko-dev/layout/generic/nsLeafFrame.h

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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 http://mozilla.org/MPL/2.0/. */
/* base class for rendering objects that do not have child lists */
#ifndef nsLeafFrame_h___
#define nsLeafFrame_h___
#include "mozilla/Attributes.h"
#include "nsIFrame.h"
#include "nsDisplayList.h"
/**
* Abstract class that provides simple fixed-size layout for leaf objects
* (e.g. images, form elements, etc.). Deriviations provide the implementation
* of the GetDesiredSize method. The rendering method knows how to render
* borders and backgrounds.
*/
class nsLeafFrame : public nsIFrame {
public:
NS_DECL_ABSTRACT_FRAME(nsLeafFrame)
// nsIFrame replacements
void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) override;
/**
* Both GetMinISize and GetPrefISize will return whatever GetIntrinsicISize
* returns.
*/
virtual nscoord GetMinISize(gfxContext* aRenderingContext) override;
virtual nscoord GetPrefISize(gfxContext* aRenderingContext) override;
/**
* Our auto size is just intrinsic width and intrinsic height.
*/
mozilla::LogicalSize ComputeAutoSize(
gfxContext* aRenderingContext, mozilla::WritingMode aWM,
const mozilla::LogicalSize& aCBSize, nscoord aAvailableISize,
const mozilla::LogicalSize& aMargin,
const mozilla::LogicalSize& aBorderPadding,
const mozilla::StyleSizeOverrides& aSizeOverrides,
mozilla::ComputeSizeFlags aFlags) override;
/**
* Each of our subclasses should provide its own Reflow impl:
*/
virtual void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override = 0;
virtual bool IsFrameOfType(uint32_t aFlags) const override {
// We don't actually contain a block, but we do always want a
// computed width, so tell a little white lie here.
return nsIFrame::IsFrameOfType(aFlags &
~(nsIFrame::eReplacedContainsBlock));
}
protected:
nsLeafFrame(ComputedStyle* aStyle, nsPresContext* aPresContext, ClassID aID)
: nsIFrame(aStyle, aPresContext, aID) {}
virtual ~nsLeafFrame();
/**
* Return the intrinsic isize of the frame's content area. Note that this
* should not include borders or padding and should not depend on the applied
* styles.
*/
virtual nscoord GetIntrinsicISize() = 0;
/**
* Return the intrinsic bsize of the frame's content area. This should not
* include border or padding. This will only matter if the specified bsize
* is auto. Note that subclasses must either implement this or override
* Reflow and ComputeAutoSize; the default Reflow and ComputeAutoSize impls
* call this method.
*/
virtual nscoord GetIntrinsicBSize();
/**
* Set aDesiredSize to be the available size
*/
void SizeToAvailSize(const ReflowInput& aReflowInput,
ReflowOutput& aDesiredSize);
};
#endif /* nsLeafFrame_h___ */