gecko-dev/layout/generic/nsLeafFrame.h

139 строки
5.3 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* base class for rendering objects that do not have child lists */
#ifndef nsLeafFrame_h___
#define nsLeafFrame_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_FRAMEARENA_HELPERS
// nsIFrame replacements
NS_IMETHOD BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists) {
DO_GLOBAL_REFLOW_COUNT_DSP("nsLeafFrame");
return DisplayBorderBackgroundOutline(aBuilder, aLists);
}
/**
* Both GetMinWidth and GetPrefWidth will return whatever GetIntrinsicWidth
* returns.
*/
virtual nscoord GetMinWidth(nsRenderingContext *aRenderingContext);
virtual nscoord GetPrefWidth(nsRenderingContext *aRenderingContext);
/**
* Our auto size is just intrinsic width and intrinsic height.
*/
virtual nsSize ComputeAutoSize(nsRenderingContext *aRenderingContext,
nsSize aCBSize, nscoord aAvailableWidth,
nsSize aMargin, nsSize aBorder,
nsSize aPadding, bool aShrinkWrap);
/**
* Reflow our frame. This will use the computed width plus borderpadding for
* the desired width, and use the return value of GetIntrinsicHeight plus
* borderpadding for the desired height. Ascent will be set to the height,
* and descent will be set to 0.
*/
NS_IMETHOD Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus);
/**
* This method does most of the work that Reflow() above need done.
*/
NS_IMETHOD DoReflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aDesiredSize,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus);
virtual bool IsFrameOfType(PRUint32 aFlags) const
{
// 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) : nsFrame(aContext) {}
virtual ~nsLeafFrame();
/**
* Return the intrinsic width 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 GetIntrinsicWidth() = 0;
/**
* Return the intrinsic height of the frame's content area. This should not
* include border or padding. This will only matter if the specified height
* 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 GetIntrinsicHeight();
/**
* Subroutine to add in borders and padding
*/
void AddBordersAndPadding(const nsHTMLReflowState& aReflowState,
nsHTMLReflowMetrics& aDesiredSize);
/**
* Set aDesiredSize to be the available size
*/
void SizeToAvailSize(const nsHTMLReflowState& aReflowState,
nsHTMLReflowMetrics& aDesiredSize);
};
#endif /* nsLeafFrame_h___ */