gecko-dev/layout/generic/nsHTMLReflowCommand.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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* 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
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*
* 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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#ifndef nsHTMLReflowCommand_h___
#define nsHTMLReflowCommand_h___
#include "nsReflowType.h"
#include "nsVoidArray.h"
#include <stdio.h>
#include "nsIAtom.h"
class nsIFrame;
class nsPresContext;
class nsIRenderingContext;
struct nsHTMLReflowMetrics;
struct nsSize;
// Reflow command flags
#define NS_RC_CREATED_DURING_DOCUMENT_LOAD 0x0001
/**
* A reflow command is an object that is generated in response to a content
* model change notification. The reflow command is given to a presentation
* shell where it is queued and then dispatched by invoking the reflow
* commands's Dispatch() member function.
*
* Reflow command processing follows a path from the root frame down to the
* target frame (the frame for which the reflow command is destined). Reflow
* commands are processed by invoking the frame's Reflow() member function.
*
* The typical flow of control for a given reflow command starts with a content
* change notification. The content notifications are sent to document observers.
* The presentation shell forwards the notifications to the style set. The style
* system responds to the notifications by creating new frame (or destroying
* existing frames) as appropriate, and then generating a reflow command.
*
* @see nsIDocumentObserver
* @see nsIStyleSet
* @see nsIFrameReflow#Reflow()
* @see nsIPresShell#AppendReflowCommand()
* @see nsIPresShell#ProcessReflowCommands()
*/
class nsHTMLReflowCommand {
public:
/**
* Construct an HTML reflow command of type aReflowType and with target
* frame aTargetFrame. You can also specify an optional child frame, e.g.
* to indicate the inserted child frame
*/
nsHTMLReflowCommand(nsIFrame* aTargetFrame,
nsReflowType aReflowType,
nsIAtom* aChildListName);
~nsHTMLReflowCommand();
/**
* Get the target of the reflow command.
*/
nsIFrame* GetTarget() const { return mTargetFrame; }
/**
* Get the type of reflow command.
*/
nsReflowType Type() const { return mType; }
/**
* Returns the name of the child list to which the child frame belongs.
* Only used for reflow command types FrameAppended, FrameInserted, and
* FrameRemoved
*
* Returns nsnull if the child frame is associated with the unnamed
* principal child list
*/
nsIAtom* GetChildListName() const { return mListName; }
/**
* Dump out the reflow-command to out
*/
nsresult List(FILE* out) const;
/**
* Get/set reflow command flags
*/
PRInt32 GetFlagBits() { return mFlags; }
void AddFlagBits(PRInt32 aBits) { mFlags |= aBits; }
void RemoveFlagBits(PRInt32 aBits) { mFlags &= ~aBits; }
/**
* DEPRECATED compatibility methods
*/
nsresult GetTarget(nsIFrame*& aTargetFrame) const {
aTargetFrame = mTargetFrame;
return NS_OK;
}
nsresult GetType(nsReflowType& aReflowType) const {
aReflowType = mType;
return NS_OK;
}
nsresult GetChildListName(nsIAtom*& aListName) const {
aListName = mListName;
NS_IF_ADDREF(aListName);
return NS_OK;
}
private:
nsReflowType mType;
nsIFrame* mTargetFrame;
nsCOMPtr<nsIAtom> mListName;
// XXXbz remove the flags? They're not being used for much...
PRInt32 mFlags;
};
#endif /* nsHTMLReflowCommand_h___ */