layout/generic/nsAutoCopyListener.h

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   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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   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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  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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  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
  20  * the Initial Developer. All Rights Reserved.
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  37
  38 #ifndef nsAutoCopyListener_h_
  39 #define nsAutoCopyListener_h_
  40
  41 #include "nsISelectionListener.h"
  42 #include "nsISelectionPrivate.h"
  43
  44 class nsAutoCopyListener : public nsISelectionListener
  45 {
  46 public:
  47   NS_DECL_ISUPPORTS
  48   NS_DECL_NSISELECTIONLISTENER
  49
  50   void Listen(nsISelectionPrivate *aSelection)
  51   {
  52       NS_ASSERTION(aSelection, "Null selection passed to Listen()");
  53       aSelection->AddSelectionListener(this);
  54   }
  55
  56   static nsAutoCopyListener* GetInstance()
  57   {
  58     if (!sInstance) {
  59       sInstance = new nsAutoCopyListener();
  60       if (!sInstance)
  61         return nsnull;
  62
  63       NS_ADDREF(sInstance);
  64     }
  65
  66     return sInstance;
  67   }
  68
  69   static void Shutdown()
  70   {
  71     NS_IF_RELEASE(sInstance);
  72   }
  73
  74 private:
  75   static nsAutoCopyListener* sInstance;
  76 };
  77
  78 #endif