layout/base/nsIReflowCallback.h

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   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
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  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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  14  *
  15  * The Original Code is Mozilla Communicator client code.
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  17  * The Initial Developer of the Original Code is
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  19  * Portions created by the Initial Developer are Copyright (C) 1998
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  22  * Contributor(s):
  23  *   Original Author: David Hyatt (hyatt@netscape.com)
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  38 #ifndef nsIReflowCallback_h___
  39 #define nsIReflowCallback_h___
  40
  41 /**
  42  * Reflow callback interface.
  43  * These are not refcounted. Objects must be removed from the presshell
  44  * callback list before they die.
  45  * Protocol: objects will either get a ReflowFinished() call when a reflow
  46  * has finished or a ReflowCallbackCanceled() call if the shell is destroyed,
  47  * whichever happens first. If the object is explicitly removed from the shell
  48  * (using nsIPresShell::CancelReflowCallback()) before that occurs then neither
  49  * of the callback methods are called.
  50  */
  51 class nsIReflowCallback {
  52 public:
  53   /**
  54    * The presshell calls this when reflow has finished. Return PR_TRUE if
  55    * you need a Flush_Layout to happen after this.
  56    */
  57   virtual PRBool ReflowFinished() = 0;
  58   /**
  59    * The presshell calls this on outstanding callback requests in its
  60    * Destroy() method. The shell removes the request after calling
  61    * ReflowCallbackCanceled().
  62    */
  63   virtual void ReflowCallbackCanceled() = 0;
  64 };
  65
  66 #endif /* nsIReflowCallback_h___ */