LibreOffice Module comphelper (master)  1
weakeventlistener.cxx
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19 
21 #include <osl/diagnose.h>
22 
23 
24 namespace comphelper
25 {
26 
27 
28  using namespace ::com::sun::star::uno;
29  using namespace ::com::sun::star::lang;
30 
32  {
33  }
34 
35  OWeakEventListenerAdapter::OWeakEventListenerAdapter( Reference< XWeak > const & _rxListener, Reference< XComponent > const & _rxBroadcaster )
36  :OWeakEventListenerAdapter_Base( _rxListener, _rxBroadcaster )
37  {
38  // add ourself as listener to the broadcaster
39  OSL_ENSURE( _rxBroadcaster.is(), "OWeakEventListenerAdapter::OWeakEventListenerAdapter: invalid broadcaster!" );
40  if ( _rxBroadcaster.is() )
41  {
42  osl_atomic_increment( &m_refCount );
43  {
44  _rxBroadcaster->addEventListener( this );
45  }
46  osl_atomic_decrement( &m_refCount );
47  OSL_ENSURE( m_refCount > 0, "OWeakEventListenerAdapter::OWeakEventListenerAdapter: oops - not to be used with implementations which hold their listeners weak!" );
48  // the one and only reason for this adapter class (A) is to add as listener to a component (C) which
49  // holds its listeners hard, and forward all calls then to another listener (L) which is
50  // held weak by A.
51  // Now if C holds listeners weak, then we do not need A, we can add L directly to C.
52  }
53 
54  OSL_ENSURE( getListener().is(), "OWeakEventListenerAdapter::OWeakEventListenerAdapter: invalid listener (does not support the XEventListener interface)!" );
55  }
56 
57 
58  void SAL_CALL OWeakEventListenerAdapter::disposing( )
59  {
60  Reference< XComponent > xBroadcaster( getBroadcaster( ), UNO_QUERY );
61  OSL_ENSURE( xBroadcaster.is(), "OWeakEventListenerAdapter::disposing: broadcaster is invalid in the meantime! How this?" );
62  if ( xBroadcaster.is() )
63  {
64  xBroadcaster->removeEventListener( this );
65  }
66 
67  resetListener();
68  }
69 
70 
71 } // namespace comphelper
72 
73 
74 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
css::uno::Reference< css::uno::XInterface > getListener() const
yet another base for weak listener adapters, this time with some type safety