xref: /AOO41X/main/comphelper/inc/comphelper/weakeventlistener.hxx (revision 9877b273795ec465a3ce9c15d738eb34c0455705)
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21 
22 
23 
24 #ifndef COMPHELPER_WEAKEVENTLISTENER_HXX
25 #define COMPHELPER_WEAKEVENTLISTENER_HXX
26 
27 #include <cppuhelper/compbase1.hxx>
28 #include <com/sun/star/lang/XComponent.hpp>
29 #include <com/sun/star/uno/XWeak.hpp>
30 #include <cppuhelper/weakref.hxx>
31 #include <comphelper/broadcasthelper.hxx>
32 #include "comphelper/comphelperdllapi.h"
33 
34 //.........................................................................
35 namespace comphelper
36 {
37 //.........................................................................
38 
39     //=====================================================================
40     //= OWeakListenerAdapterBase
41     //=====================================================================
42     /** (the base for) an adapter which allows to add as listener to a foreign component, without
43         being held hard.
44 
45         <p>The idea is that this adapter is added as listener to a foreign component, which usually
46         holds it's listener hard. The adapter itself knows the real listener as weak reference,
47         thus not affecting it's life time.</p>
48     */
49     class OWeakListenerAdapterBase : public OBaseMutex
50     {
51     private:
52         ::com::sun::star::uno::WeakReference< ::com::sun::star::uno::XInterface >
53                 m_aListener;
54         ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >
55                 m_xBroadcaster;
56 
57     protected:
58         inline ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >
getListener() const59                 getListener( ) const
60         {
61             return m_aListener.get();
62         }
63 
64         inline const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >&
getBroadcaster() const65                 getBroadcaster( ) const
66         {
67             return m_xBroadcaster;
68         }
69 
resetListener()70         inline void resetListener( )
71         {
72             m_aListener.clear();
73         }
74 
75 
76     protected:
OWeakListenerAdapterBase(const::com::sun::star::uno::Reference<::com::sun::star::uno::XWeak> & _rxListener,const::com::sun::star::uno::Reference<::com::sun::star::uno::XInterface> & _rxBroadcaster)77         inline OWeakListenerAdapterBase(
78             const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak >& _rxListener,
79             const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >& _rxBroadcaster
80         )
81             :m_aListener    (  _rxListener )
82             ,m_xBroadcaster ( _rxBroadcaster )
83         {
84         }
85 
86     protected:
87         virtual ~OWeakListenerAdapterBase();
88     };
89 
90 
91     //=====================================================================
92     //= OWeakListenerAdapter
93     //=====================================================================
94     template< class BROADCASTER, class LISTENER >
95     /** yet another base for weak listener adapters, this time with some type safety
96 
97         <p>Note that derived classes need to overwrite all virtual methods of their interface
98         except XEventListener::disposing, and forward it to their master listener.</p>
99 
100         <p>Addtionally, derived classes need to add themself as listener to the broadcaster,
101         as this can't be done in a generic way</p>
102     */
103     class OWeakListenerAdapter
104             :public ::cppu::WeakComponentImplHelper1 < LISTENER >
105             ,public OWeakListenerAdapterBase
106     {
107     protected:
108         /** ctor
109             <p>Note that derived classes still need to add themself as listener to the broadcaster,
110             as this can't be done in a generic way</p>
111         */
112         OWeakListenerAdapter(
113             const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak >& _rxListener,
114             const ::com::sun::star::uno::Reference< BROADCASTER >& _rxBroadcaster
115         );
116 
117     protected:
getListener() const118         inline  ::com::sun::star::uno::Reference< LISTENER > getListener( ) const
119         {
120             return  ::com::sun::star::uno::Reference< LISTENER >( OWeakListenerAdapterBase::getListener(), ::com::sun::star::uno::UNO_QUERY );
121         }
122 
123         // XEventListener overridables
124         virtual void SAL_CALL disposing( const ::com::sun::star::lang::EventObject& Source ) throw (::com::sun::star::uno::RuntimeException);
125 
126     protected:
127         // OComponentHelper overridables
128         // to be overridden, again - the derived class should revoke the listener from the broadcaster
129         virtual void SAL_CALL disposing( ) = 0;
130     };
131 
132     //=====================================================================
133     //= OWeakEventListenerAdapter
134     //=====================================================================
135     typedef OWeakListenerAdapter    <   ::com::sun::star::lang::XComponent
136                                     ,   ::com::sun::star::lang::XEventListener
137                                     >   OWeakEventListenerAdapter_Base;
138     /** the most simple listener adapter: for XEventListeners at XComponents
139     */
140     class COMPHELPER_DLLPUBLIC OWeakEventListenerAdapter : public OWeakEventListenerAdapter_Base
141     {
142     public:
143         OWeakEventListenerAdapter(
144             ::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak > _rxListener,
145             ::com::sun::star::uno::Reference< ::com::sun::star::lang::XComponent > _rxBroadcaster
146         );
147 
148         // nothing to do except an own ctor - the forwarding of the "disposing" is already done
149         // in the base class
150 
151     protected:
152         using OWeakEventListenerAdapter_Base::disposing;
153         virtual void SAL_CALL disposing( );
154     };
155 
156     //=====================================================================
157     //= OWeakListenerAdapter
158     //=====================================================================
159     //---------------------------------------------------------------------
160     template< class BROADCASTER, class LISTENER >
OWeakListenerAdapter(const::com::sun::star::uno::Reference<::com::sun::star::uno::XWeak> & _rxListener,const::com::sun::star::uno::Reference<BROADCASTER> & _rxBroadcaster)161     OWeakListenerAdapter< BROADCASTER, LISTENER >::OWeakListenerAdapter(
162         const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak >& _rxListener,
163         const ::com::sun::star::uno::Reference< BROADCASTER >& _rxBroadcaster
164     )
165         : ::cppu::WeakComponentImplHelper1< LISTENER >( m_aMutex )
166         , OWeakListenerAdapterBase( _rxListener, _rxBroadcaster )
167     {
168     }
169 
170     //---------------------------------------------------------------------
171     template< class BROADCASTER, class LISTENER >
disposing(const::com::sun::star::lang::EventObject & _rSource)172     void SAL_CALL OWeakListenerAdapter< BROADCASTER, LISTENER >::disposing( const ::com::sun::star::lang::EventObject& _rSource ) throw (::com::sun::star::uno::RuntimeException)
173     {
174         ::com::sun::star::uno::Reference< LISTENER > xListener( getListener() );
175         if ( xListener.is() )
176             xListener->disposing( _rSource );
177     }
178 
179 //.........................................................................
180 }   // namespace comphelper
181 //.........................................................................
182 
183 #endif// COMPHELPER_WEAKEVENTLISTENER_HXX
184 
185 
186