gecko-dev/layout/generic/nsSplittableFrame.h

119 lines
4.3 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
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* ***** END LICENSE BLOCK ***** */
/*
* base class for rendering objects that can be split across lines,
* columns, or pages
*/
#ifndef nsSplittableFrame_h___
#define nsSplittableFrame_h___
#include "nsFrame.h"
// Derived class that allows splitting
class nsSplittableFrame : public nsFrame
{
public:
NS_DECL_FRAMEARENA_HELPERS
NS_IMETHOD Init(nsIContent* aContent,
nsIFrame* aParent,
nsIFrame* aPrevInFlow);
virtual nsSplittableType GetSplittableType() const;
virtual void Destroy();
/*
* Frame continuations can be either fluid or not:
* Fluid continuations ("in-flows") are the result of line breaking,
* column breaking, or page breaking.
* Other (non-fluid) continuations can be the result of BiDi frame splitting.
* A "flow" is a chain of fluid continuations.
*/
// Get the previous/next continuation, regardless of its type (fluid or non-fluid).
virtual nsIFrame* GetPrevContinuation() const;
virtual nsIFrame* GetNextContinuation() const;
// Set a previous/next non-fluid continuation.
NS_IMETHOD SetPrevContinuation(nsIFrame*);
NS_IMETHOD SetNextContinuation(nsIFrame*);
// Get the first/last continuation for this frame.
virtual nsIFrame* GetFirstContinuation() const;
virtual nsIFrame* GetLastContinuation() const;
#ifdef DEBUG
// Can aFrame2 be reached from aFrame1 by following prev/next continuations?
static PRBool IsInPrevContinuationChain(nsIFrame* aFrame1, nsIFrame* aFrame2);
static PRBool IsInNextContinuationChain(nsIFrame* aFrame1, nsIFrame* aFrame2);
#endif
// Get the previous/next continuation, only if it is fluid (an "in-flow").
nsIFrame* GetPrevInFlow() const;
nsIFrame* GetNextInFlow() const;
virtual nsIFrame* GetPrevInFlowVirtual() const { return GetPrevInFlow(); }
virtual nsIFrame* GetNextInFlowVirtual() const { return GetNextInFlow(); }
// Set a previous/next fluid continuation.
NS_IMETHOD SetPrevInFlow(nsIFrame*);
NS_IMETHOD SetNextInFlow(nsIFrame*);
// Get the first/last frame in the current flow.
virtual nsIFrame* GetFirstInFlow() const;
virtual nsIFrame* GetLastInFlow() const;
// Remove the frame from the flow. Connects the frame's prev-in-flow
// and its next-in-flow. This should only be called in frame Destroy() methods.
static void RemoveFromFlow(nsIFrame* aFrame);
protected:
nsSplittableFrame(nsStyleContext* aContext) : nsFrame(aContext) {}
#ifdef DEBUG
virtual void DumpBaseRegressionData(nsPresContext* aPresContext, FILE* out, PRInt32 aIndent);
#endif
nsIFrame* mPrevContinuation;
nsIFrame* mNextContinuation;
};
#endif /* nsSplittableFrame_h___ */