gecko-dev/layout/generic/nsLeafFrame.h

109 lines
3.9 KiB
C++

/* -*- 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/. */
/* base class for rendering objects that do not have child lists */
#ifndef nsLeafFrame_h___
#define nsLeafFrame_h___
#include "mozilla/Attributes.h"
#include "nsFrame.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 nsFrame {
public:
NS_DECL_ABSTRACT_FRAME(nsLeafFrame)
// nsIFrame replacements
virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) override {
DO_GLOBAL_REFLOW_COUNT_DSP("nsLeafFrame");
DisplayBorderBackgroundOutline(aBuilder, aLists);
}
/**
* 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.
*/
virtual mozilla::LogicalSize
ComputeAutoSize(gfxContext* aRenderingContext,
mozilla::WritingMode aWM,
const mozilla::LogicalSize& aCBSize,
nscoord aAvailableISize,
const mozilla::LogicalSize& aMargin,
const mozilla::LogicalSize& aBorder,
const mozilla::LogicalSize& aPadding,
ComputeSizeFlags aFlags) override;
/**
* Reflow our frame. This will use the computed width plus borderpadding for
* the desired width, and use the return value of GetIntrinsicBSize plus
* borderpadding for the desired height. Ascent will be set to the height,
* and descent will be set to 0.
*/
virtual void Reflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) override;
/**
* This method does most of the work that Reflow() above need done.
*/
virtual void DoReflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus);
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 nsFrame::IsFrameOfType(aFlags & ~(nsIFrame::eReplacedContainsBlock));
}
protected:
nsLeafFrame(nsStyleContext* aContext, ClassID aID)
: nsFrame(aContext, 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___ */