include/svl/broadcast.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
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   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
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  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19 #ifndef INCLUDED_SVL_BROADCAST_HXX
  20 #define INCLUDED_SVL_BROADCAST_HXX
  21
  22 #include <svl/svldllapi.h>
  23
  24 #include <vector>
  25
  26 class SvtListener;
  27 class SfxHint;
  28
  29 class SVL_DLLPUBLIC SvtBroadcaster
  30 {
  31 public:
  32     friend class SvtListener;
  33
  34     typedef std::vector<SvtListener*> ListenersType;
  35
  36 private:
  37     const SvtBroadcaster&   operator=(const SvtBroadcaster &) = delete;
  38
  39     /**
  40      * Ensure that the container doesn't contain any duplicated listener
  41      * entries. As a side effect, the listeners get sorted by pointer values
  42      * after this call.
  43      */
  44     void Normalize() const;
  45
  46     void Add( SvtListener* p );
  47     void Remove( SvtListener* p );
  48
  49 protected:
  50     virtual void            ListenersGone();
  51
  52 public:
  53                             SvtBroadcaster();
  54                             SvtBroadcaster( const SvtBroadcaster &rBC );
  55     virtual                 ~SvtBroadcaster();
  56
  57     void                    Broadcast( const SfxHint &rHint );
  58
  59     ListenersType& GetAllListeners();
  60     const ListenersType& GetAllListeners() const;
  61
  62     bool HasListeners() const;
  63
  64     /**
  65      * Listeners and broadcasters are M:N relationship.  If you want to
  66      * destruct them, you easily end up in O(M*N) situation; where for every
  67      * listener, you iterate all broadcasters, to remove that one listener.
  68      *
  69      * To avoid that, use this call to announce to the broadcaster it is going
  70      * to die, and the listeners do not have to bother with removing
  71      * themselves from the broadcaster - the broadcaster will not broadcast
  72      * anything after the PrepareForDesctruction() call anyway.
  73      */
  74     void PrepareForDestruction();
  75
  76 private:
  77     /// contains only one of each listener, which is enforced by SvtListener
  78     mutable ListenersType maListeners;
  79
  80     /// When the broadcaster is about to die, collect listeners that asked for removal.
  81     mutable ListenersType maDestructedListeners;
  82
  83     /// Indicate that this broadcaster will be destructed (we indicate this on all ScColumn's broadcasters during the ScTable destruction, eg.)
  84     bool mbAboutToDie:1;
  85     bool mbDisposing:1;
  86     mutable bool mbNormalized:1;
  87     mutable bool mbDestNormalized:1;
  88 };
  89
  90
  91 #endif
  92
  93 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */