xref: /AOO41X/main/comphelper/source/misc/accessiblecontexthelper.cxx (revision dde7d3faf6dcd9cbeb7b48ba6d0cea5ffcc883d0)
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21 
22 
23 
24 // MARKER(update_precomp.py): autogen include statement, do not remove
25 #include "precompiled_comphelper.hxx"
26 #include <comphelper/accessiblecontexthelper.hxx>
27 #include <comphelper/accessibleeventbuffer.hxx>
28 #include <osl/diagnose.h>
29 #include <cppuhelper/weakref.hxx>
30 #include <com/sun/star/accessibility/AccessibleEventId.hpp>
31 #include <com/sun/star/accessibility/AccessibleStateType.hpp>
32 #include <comphelper/accessibleeventnotifier.hxx>
33 
34 //.........................................................................
35 namespace comphelper
36 {
37 //.........................................................................
38 
39     using namespace ::com::sun::star::uno;
40     using namespace ::com::sun::star::lang;
41     using namespace ::com::sun::star::accessibility;
42 
43     //=====================================================================
44     //= OContextHelper_Impl
45     //=====================================================================
46     /** implementation class for OAccessibleContextHelper. No own thread safety!
47     */
48     class OContextHelper_Impl
49     {
50     private:
51         OAccessibleContextHelper*           m_pAntiImpl;        // the owning instance
52         IMutex*                             m_pExternalLock;    // the optional additional external lock
53 
54         ::cppu::OInterfaceContainerHelper*  m_pEventListeners;
55         WeakReference< XAccessible >        m_aCreator;         // the XAccessible which created our XAccessibleContext
56 
57         AccessibleEventNotifier::TClientId  m_nClientId;
58 
59     public:
getCreator() const60         inline  Reference< XAccessible >    getCreator( ) const                 { return m_aCreator; }
61         inline  void                        setCreator( const Reference< XAccessible >& _rAcc );
62 
getExternalLock()63         inline  IMutex*                     getExternalLock( )                  { return m_pExternalLock; }
setExternalLock(IMutex * _pLock)64         inline  void                        setExternalLock( IMutex* _pLock )   { m_pExternalLock = _pLock; }
65 
66         inline  AccessibleEventNotifier::TClientId
getClientId() const67                                             getClientId() const                 { return m_nClientId; }
setClientId(const AccessibleEventNotifier::TClientId _nId)68         inline  void                        setClientId( const AccessibleEventNotifier::TClientId _nId )
69                                                                                 { m_nClientId = _nId; }
70 
71     public:
OContextHelper_Impl(OAccessibleContextHelper * _pAntiImpl)72         OContextHelper_Impl( OAccessibleContextHelper* _pAntiImpl )
73             :m_pAntiImpl( _pAntiImpl )
74             ,m_pExternalLock( NULL )
75             ,m_pEventListeners( NULL )
76             ,m_nClientId( 0 )
77         {
78         }
79     };
80 
81     //---------------------------------------------------------------------
setCreator(const Reference<XAccessible> & _rAcc)82     inline  void OContextHelper_Impl::setCreator( const Reference< XAccessible >& _rAcc )
83     {
84         m_aCreator = _rAcc;
85     }
86 
87     //=====================================================================
88     //= OAccessibleContextHelper
89     //=====================================================================
90     //---------------------------------------------------------------------
OAccessibleContextHelper()91     OAccessibleContextHelper::OAccessibleContextHelper( )
92         :OAccessibleContextHelper_Base( GetMutex() )
93         ,m_pImpl( NULL )
94     {
95         m_pImpl = new OContextHelper_Impl( this );
96     }
97 
98     //---------------------------------------------------------------------
OAccessibleContextHelper(IMutex * _pExternalLock)99     OAccessibleContextHelper::OAccessibleContextHelper( IMutex* _pExternalLock )
100         :OAccessibleContextHelper_Base( GetMutex() )
101         ,m_pImpl( NULL )
102     {
103         m_pImpl = new OContextHelper_Impl( this );
104         m_pImpl->setExternalLock( _pExternalLock );
105     }
106 
107     //---------------------------------------------------------------------
forgetExternalLock()108     void OAccessibleContextHelper::forgetExternalLock()
109     {
110         m_pImpl->setExternalLock( NULL );
111     }
112 
113     //---------------------------------------------------------------------
~OAccessibleContextHelper()114     OAccessibleContextHelper::~OAccessibleContextHelper( )
115     {
116         forgetExternalLock();
117             // this ensures that the lock, which may be already destroyed as part of the derivee,
118             // is not used anymore
119 
120         ensureDisposed();
121 
122         delete m_pImpl;
123         m_pImpl = NULL;
124     }
125 
126     //---------------------------------------------------------------------
getExternalLock()127     IMutex* OAccessibleContextHelper::getExternalLock( )
128     {
129         return m_pImpl->getExternalLock();
130     }
131 
132     //---------------------------------------------------------------------
disposing()133     void SAL_CALL OAccessibleContextHelper::disposing()
134     {
135         ::osl::ClearableMutexGuard aGuard( GetMutex() );
136 
137         if ( m_pImpl->getClientId( ) )
138         {
139             AccessibleEventNotifier::revokeClientNotifyDisposing( m_pImpl->getClientId( ), *this );
140             m_pImpl->setClientId( 0 );
141         }
142     }
143 
144     //---------------------------------------------------------------------
addEventListener(const Reference<XAccessibleEventListener> & _rxListener)145     void SAL_CALL OAccessibleContextHelper::addEventListener( const Reference< XAccessibleEventListener >& _rxListener ) throw (RuntimeException)
146     {
147         OMutexGuard aGuard( getExternalLock() );
148             // don't use the OContextEntryGuard - it will throw an exception if we're not alive
149             // anymore, while the most recent specification for XComponent states that we should
150             // silently ignore the call in such a situation
151         if ( !isAlive() )
152         {
153             if ( _rxListener.is() )
154                 _rxListener->disposing( EventObject( *this ) );
155             return;
156         }
157 
158         if ( _rxListener.is() )
159         {
160             if ( !m_pImpl->getClientId( ) )
161                 m_pImpl->setClientId( AccessibleEventNotifier::registerClient( ) );
162 
163             AccessibleEventNotifier::addEventListener( m_pImpl->getClientId( ), _rxListener );
164         }
165     }
166 
167     //---------------------------------------------------------------------
removeEventListener(const Reference<XAccessibleEventListener> & _rxListener)168     void SAL_CALL OAccessibleContextHelper::removeEventListener( const Reference< XAccessibleEventListener >& _rxListener ) throw (RuntimeException)
169     {
170         OMutexGuard aGuard( getExternalLock() );
171             // don't use the OContextEntryGuard - it will throw an exception if we're not alive
172             // anymore, while the most recent specification for XComponent states that we should
173             // silently ignore the call in such a situation
174         if ( !isAlive() )
175             return;
176 
177         if ( _rxListener.is() )
178         {
179             sal_Int32 nListenerCount = AccessibleEventNotifier::removeEventListener( m_pImpl->getClientId( ), _rxListener );
180             if ( !nListenerCount )
181             {
182                 // no listeners anymore
183                 // -> revoke ourself. This may lead to the notifier thread dying (if we were the last client),
184                 // and at least to us not firing any events anymore, in case somebody calls
185                 // NotifyAccessibleEvent, again
186                 AccessibleEventNotifier::revokeClient( m_pImpl->getClientId( ) );
187                 m_pImpl->setClientId( 0 );
188             }
189         }
190     }
191 
192     //---------------------------------------------------------------------
NotifyAccessibleEvent(const sal_Int16 _nEventId,const Any & _rOldValue,const Any & _rNewValue)193     void SAL_CALL OAccessibleContextHelper::NotifyAccessibleEvent( const sal_Int16 _nEventId,
194         const Any& _rOldValue, const Any& _rNewValue )
195     {
196         if ( !m_pImpl->getClientId( ) )
197             // if we don't have a client id for the notifier, then we don't have listeners, then
198             // we don't need to notify anything
199             return;
200 
201         // build an event object
202         AccessibleEventObject aEvent;
203         aEvent.Source = *this;
204         aEvent.EventId = _nEventId;
205         aEvent.OldValue = _rOldValue;
206         aEvent.NewValue = _rNewValue;
207 
208         // let the notifier handle this event
209         AccessibleEventNotifier::addEvent( m_pImpl->getClientId( ), aEvent );
210     }
211 
212     //---------------------------------------------------------------------
BufferAccessibleEvent(const sal_Int16 _nEventId,const Any & _rOldValue,const Any & _rNewValue,AccessibleEventBuffer & _rBuffer)213     void SAL_CALL OAccessibleContextHelper::BufferAccessibleEvent( const sal_Int16 _nEventId,
214         const Any& _rOldValue, const Any& _rNewValue,
215         AccessibleEventBuffer & _rBuffer )
216     {
217         // TODO: this whole method (as well as the class AccessibleEventBuffer) should be removed
218         // The reasons why they have been introduces id that we needed to collect a set of events
219         // before notifying them alltogether (after releasing our mutex). With the other
220         // NotifyAccessibleEvent being asynchronous now, this should not be necessary anymore
221         // - clients could use the other version now.
222 
223         // copy our current listeners
224         Sequence< Reference< XInterface > > aListeners;
225         if ( m_pImpl->getClientId( ) )
226             aListeners = AccessibleEventNotifier::getEventListeners( m_pImpl->getClientId( ) );
227 
228         if ( aListeners.getLength() )
229         {
230             AccessibleEventObject aEvent;
231             aEvent.Source = *this;
232             OSL_ENSURE( aEvent.Source.is(), "OAccessibleContextHelper::BufferAccessibleEvent: invalid creator!" );
233             aEvent.EventId = _nEventId;
234             aEvent.OldValue = _rOldValue;
235             aEvent.NewValue = _rNewValue;
236 
237             _rBuffer.addEvent( aEvent, aListeners );
238         }
239     }
240 
241     //---------------------------------------------------------------------
isAlive() const242     sal_Bool OAccessibleContextHelper::isAlive() const
243     {
244         return !GetBroadcastHelper().bDisposed && !GetBroadcastHelper().bInDispose;
245     }
246 
247     //---------------------------------------------------------------------
ensureAlive() const248     void OAccessibleContextHelper::ensureAlive() const SAL_THROW( ( DisposedException ) )
249     {
250         if( !isAlive() )
251             throw DisposedException();
252     }
253 
254     //---------------------------------------------------------------------
ensureDisposed()255     void OAccessibleContextHelper::ensureDisposed( )
256     {
257         if ( !GetBroadcastHelper().bDisposed )
258         {
259             OSL_ENSURE( 0 == m_refCount, "OAccessibleContextHelper::ensureDisposed: this method _has_ to be called from without your dtor only!" );
260             acquire();
261             dispose();
262         }
263     }
264 
265     //---------------------------------------------------------------------
lateInit(const Reference<XAccessible> & _rxAccessible)266     void OAccessibleContextHelper::lateInit( const Reference< XAccessible >& _rxAccessible )
267     {
268         m_pImpl->setCreator( _rxAccessible );
269     }
270 
271     //---------------------------------------------------------------------
getAccessibleCreator() const272     Reference< XAccessible > OAccessibleContextHelper::getAccessibleCreator( ) const
273     {
274         return m_pImpl->getCreator();
275     }
276 
277     //---------------------------------------------------------------------
getAccessibleIndexInParent()278     sal_Int32 SAL_CALL OAccessibleContextHelper::getAccessibleIndexInParent(  ) throw (RuntimeException)
279     {
280         OExternalLockGuard aGuard( this );
281 
282         // -1 for child not found/no parent (according to specification)
283         sal_Int32 nRet = -1;
284 
285         try
286         {
287 
288             Reference< XAccessibleContext > xParentContext( implGetParentContext() );
289 
290             //  iterate over parent's children and search for this object
291             if ( xParentContext.is() )
292             {
293                 // our own XAccessible for comparing with the children of our parent
294                 Reference< XAccessible > xCreator( m_pImpl->getCreator() );
295 
296                 OSL_ENSURE( xCreator.is(), "OAccessibleContextHelper::getAccessibleIndexInParent: invalid creator!" );
297                     // two ideas why this could be NULL:
298                     // * nobody called our late ctor (init), so we never had a creator at all -> bad
299                     // * the creator is already dead. In this case, we should have been disposed, and
300                     //   never survived the above OContextEntryGuard.
301                     // in all other situations the creator should be non-NULL
302 
303                 if ( xCreator.is() )
304                 {
305                     sal_Int32 nChildCount = xParentContext->getAccessibleChildCount();
306                     for ( sal_Int32 nChild = 0; ( nChild < nChildCount ) && ( -1 == nRet ); ++nChild )
307                     {
308                         Reference< XAccessible > xChild( xParentContext->getAccessibleChild( nChild ) );
309                         if ( xChild.get() == xCreator.get() )
310                             nRet = nChild;
311                     }
312                 }
313             }
314         }
315         catch( const Exception& )
316         {
317             OSL_ENSURE( sal_False, "OAccessibleContextHelper::getAccessibleIndexInParent: caught an exception!" );
318         }
319 
320         return nRet;
321     }
322 
323     //---------------------------------------------------------------------
getLocale()324     Locale SAL_CALL OAccessibleContextHelper::getLocale(  ) throw (IllegalAccessibleComponentStateException, RuntimeException)
325     {
326         // simply ask the parent
327         Reference< XAccessible > xParent = getAccessibleParent();
328         Reference< XAccessibleContext > xParentContext;
329         if ( xParent.is() )
330             xParentContext = xParent->getAccessibleContext();
331 
332         if ( !xParentContext.is() )
333             throw IllegalAccessibleComponentStateException( ::rtl::OUString(), *this );
334 
335         return xParentContext->getLocale();
336     }
337 
338     //---------------------------------------------------------------------
implGetParentContext()339     Reference< XAccessibleContext > OAccessibleContextHelper::implGetParentContext() SAL_THROW( ( RuntimeException ) )
340     {
341         Reference< XAccessible > xParent = getAccessibleParent();
342         Reference< XAccessibleContext > xParentContext;
343         if ( xParent.is() )
344             xParentContext = xParent->getAccessibleContext();
345         return xParentContext;
346     }
347 
348 //.........................................................................
349 }   // namespace comphelper
350 //.........................................................................
351 
352 
353