gecko-dev/layout/generic/nsBlockReflowContext.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (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/NPL/
*
* 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 Communicator client code.
*
* The Initial Developer of the Original Code is Netscape Communications
* Corporation. Portions created by Netscape are Copyright (C) 1998
* Netscape Communications Corporation. All Rights Reserved.
*/
#ifndef nsBlockReflowContext_h___
#define nsBlockReflowContext_h___
#include "nsIHTMLReflow.h"
class nsBlockFrame;
class nsIFrame;
class nsIPresContext;
class nsLineLayout;
struct nsStylePosition;
struct nsStyleSpacing;
/**
* An encapsulation of the state and algorithm for reflowing block frames.
*/
class nsBlockReflowContext {
public:
nsBlockReflowContext(nsIPresContext& aPresContext,
const nsHTMLReflowState& aParentRS,
PRBool aComputeMaxElementSize);
~nsBlockReflowContext() { }
void SetNextRCFrame(nsIFrame* aNextRCFrame) {
mNextRCFrame = aNextRCFrame;
}
nsIFrame* GetNextRCFrame() const {
return mNextRCFrame;
}
nsresult ReflowBlock(nsIFrame* aFrame,
const nsRect& aSpace,
PRBool aApplyTopMargin,
nscoord aPrevBottomMargin,
PRBool aIsAdjacentWithTop,
nsMargin& aComputedOffsets,
nsReflowStatus& aReflowStatus);
PRBool PlaceBlock(PRBool aForceFit,
const nsMargin& aComputedOffsets,
nscoord* aBottomMarginResult,
nsRect& aInFlowBounds,
nsRect& aCombinedRect);
nscoord GetCarriedOutBottomMargin() const {
return mMetrics.mCarriedOutBottomMargin;
}
nscoord GetTopMargin() const {
return mTopMargin;
}
const nsMargin& GetMargin() const {
return mMargin;
}
const nsHTMLReflowMetrics& GetMetrics() const {
return mMetrics;
}
const nsSize& GetMaxElementSize() const {
return mMaxElementSize;
}
// Compute the largest of two adjacent vertical margins, as per the
// CSS2 spec section 8.3.1
static nscoord MaxMargin(nscoord a, nscoord b) {
if (a < 0) {
if (b < 0) {
if (a < b) return a;
return b;
}
return b + a;
}
else if (b < 0) {
return a + b;
}
if (a > b) return a;
return b;
}
static PRBool IsHTMLParagraph(nsIFrame* aFrame);
static nscoord ComputeCollapsedTopMargin(nsIPresContext& aPresContext,
nsHTMLReflowState& aRS);
protected:
nsStyleUnit GetRealMarginLeftUnit();
nsStyleUnit GetRealMarginRightUnit();
nsIPresContext& mPresContext;
const nsHTMLReflowState& mOuterReflowState;
nsIFrame* mFrame;
nsRect mSpace;
nsIFrame* mNextRCFrame;
// Spacing style for the frame we are reflowing; only valid after reflow
const nsStyleSpacing* mStyleSpacing;
nsMargin mMargin;
nscoord mX, mY;
nsHTMLReflowMetrics mMetrics;
nscoord mTopMargin;
nsSize mMaxElementSize;
PRBool mIsTable;
};
#endif /* nsBlockReflowContext_h___ */