vcl/inc/impdel.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   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
  13  *   with this work for additional information regarding copyright
  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
  20 #ifndef INCLUDED_VCL_IMPDEL_HXX
  21 #define INCLUDED_VCL_IMPDEL_HXX
  22
  23 #include <list>
  24
  25 namespace vcl
  26 {
  27
  28 class DeletionListener;
  29
  30 class DeletionNotifier
  31 {
  32     std::list< DeletionListener* > m_aListeners;
  33     protected:
  34     DeletionNotifier() {}
  35
  36     ~DeletionNotifier()
  37     { notifyDelete(); }
  38
  39     inline void notifyDelete();
  40
  41     public:
  42     void addDel( DeletionListener* pListener )
  43     { m_aListeners.push_back( pListener ); }
  44
  45     void removeDel( DeletionListener* pListener )
  46     { m_aListeners.remove( pListener ); }
  47 };
  48
  49 class DeletionListener
  50 {
  51     DeletionNotifier*  m_pNotifier;
  52     public:
  53     DeletionListener( DeletionNotifier* pNotifier )
  54     :  m_pNotifier( pNotifier )
  55        {
  56            if( m_pNotifier )
  57                m_pNotifier->addDel( this );
  58        }
  59    ~DeletionListener()
  60    {
  61        if( m_pNotifier )
  62            m_pNotifier->removeDel( this );
  63    }
  64    void deleted() { m_pNotifier = nullptr; }
  65    bool isDeleted() const { return (m_pNotifier == nullptr); }
  66 };
  67
  68 inline void DeletionNotifier::notifyDelete()
  69 {
  70     for( auto& rListener : m_aListeners )
  71        rListener->deleted();
  72
  73     m_aListeners.clear();
  74 }
  75
  76 } // namespace vcl
  77
  78 #endif // INCLUDED_VCL_IMPDEL_HXX
  79
  80 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */