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27 
28 // MARKER(update_precomp.py): autogen include statement, do not remove
29 #include "precompiled_comphelper.hxx"
30 #include <comphelper/accessiblecontexthelper.hxx>
31 #include <comphelper/accessibleeventbuffer.hxx>
32 #include <osl/diagnose.h>
33 #include <cppuhelper/weakref.hxx>
34 #include <com/sun/star/accessibility/AccessibleEventId.hpp>
35 #include <com/sun/star/accessibility/AccessibleStateType.hpp>
36 #include <comphelper/accessibleeventnotifier.hxx>
37 
38 //.........................................................................
39 namespace comphelper
40 {
41 //.........................................................................
42 
43 	using namespace ::com::sun::star::uno;
44 	using namespace ::com::sun::star::lang;
45 	using namespace ::com::sun::star::accessibility;
46 
47 	//=====================================================================
48 	//= OContextHelper_Impl
49 	//=====================================================================
50 	/** implementation class for OAccessibleContextHelper. No own thread safety!
51 	*/
52 	class OContextHelper_Impl
53 	{
54 	private:
55 		OAccessibleContextHelper*			m_pAntiImpl;		// the owning instance
56 		IMutex*								m_pExternalLock;	// the optional additional external lock
57 
58 	    ::cppu::OInterfaceContainerHelper*	m_pEventListeners;
59 		WeakReference< XAccessible >		m_aCreator;			// the XAccessible which created our XAccessibleContext
60 
61 		AccessibleEventNotifier::TClientId	m_nClientId;
62 
63 	public:
64 		inline	Reference< XAccessible >	getCreator( ) const					{ return m_aCreator; }
65 		inline	void						setCreator( const Reference< XAccessible >& _rAcc );
66 
67 		inline	IMutex*						getExternalLock( )					{ return m_pExternalLock; }
68 		inline	void						setExternalLock( IMutex* _pLock )	{ m_pExternalLock = _pLock; }
69 
70 		inline	AccessibleEventNotifier::TClientId
71 											getClientId() const					{ return m_nClientId; }
72 		inline	void						setClientId( const AccessibleEventNotifier::TClientId _nId )
73 																				{ m_nClientId = _nId; }
74 
75 	public:
76 		OContextHelper_Impl( OAccessibleContextHelper* _pAntiImpl )
77 			:m_pAntiImpl( _pAntiImpl )
78 			,m_pExternalLock( NULL )
79 			,m_pEventListeners( NULL )
80 			,m_nClientId( 0 )
81 		{
82 		}
83 	};
84 
85 	//---------------------------------------------------------------------
86 	inline	void OContextHelper_Impl::setCreator( const Reference< XAccessible >& _rAcc )
87 	{
88 		m_aCreator = _rAcc;
89 	}
90 
91 	//=====================================================================
92 	//= OAccessibleContextHelper
93 	//=====================================================================
94 	//---------------------------------------------------------------------
95 	OAccessibleContextHelper::OAccessibleContextHelper( )
96 		:OAccessibleContextHelper_Base( GetMutex() )
97 		,m_pImpl( NULL )
98 	{
99 		m_pImpl = new OContextHelper_Impl( this );
100 	}
101 
102 	//---------------------------------------------------------------------
103 	OAccessibleContextHelper::OAccessibleContextHelper( IMutex* _pExternalLock )
104 		:OAccessibleContextHelper_Base( GetMutex() )
105 		,m_pImpl( NULL )
106 	{
107 		m_pImpl = new OContextHelper_Impl( this );
108 		m_pImpl->setExternalLock( _pExternalLock );
109 	}
110 
111 	//---------------------------------------------------------------------
112 	void OAccessibleContextHelper::forgetExternalLock()
113 	{
114 		m_pImpl->setExternalLock( NULL );
115 	}
116 
117 	//---------------------------------------------------------------------
118 	OAccessibleContextHelper::~OAccessibleContextHelper( )
119 	{
120 		forgetExternalLock();
121 			// this ensures that the lock, which may be already destroyed as part of the derivee,
122 			// is not used anymore
123 
124 		ensureDisposed();
125 
126 		delete m_pImpl;
127 		m_pImpl = NULL;
128 	}
129 
130 	//---------------------------------------------------------------------
131 	IMutex* OAccessibleContextHelper::getExternalLock( )
132 	{
133 		return m_pImpl->getExternalLock();
134 	}
135 
136 	//---------------------------------------------------------------------
137 	void SAL_CALL OAccessibleContextHelper::disposing()
138 	{
139 		::osl::ClearableMutexGuard aGuard( GetMutex() );
140 
141 		if ( m_pImpl->getClientId( ) )
142 		{
143 			AccessibleEventNotifier::revokeClientNotifyDisposing( m_pImpl->getClientId( ), *this );
144 			m_pImpl->setClientId( 0 );
145 		}
146 	}
147 
148 	//---------------------------------------------------------------------
149 	void SAL_CALL OAccessibleContextHelper::addEventListener( const Reference< XAccessibleEventListener >& _rxListener ) throw (RuntimeException)
150 	{
151 		OMutexGuard aGuard( getExternalLock() );
152 			// don't use the OContextEntryGuard - it will throw an exception if we're not alive
153 			// anymore, while the most recent specification for XComponent states that we should
154 			// silently ignore the call in such a situation
155 		if ( !isAlive() )
156 		{
157 			if ( _rxListener.is() )
158 				_rxListener->disposing( EventObject( *this ) );
159 			return;
160 		}
161 
162 		if ( _rxListener.is() )
163 		{
164 			if ( !m_pImpl->getClientId( ) )
165 				m_pImpl->setClientId( AccessibleEventNotifier::registerClient( ) );
166 
167 			AccessibleEventNotifier::addEventListener( m_pImpl->getClientId( ), _rxListener );
168 		}
169 	}
170 
171 	//---------------------------------------------------------------------
172 	void SAL_CALL OAccessibleContextHelper::removeEventListener( const Reference< XAccessibleEventListener >& _rxListener ) throw (RuntimeException)
173 	{
174 		OMutexGuard aGuard( getExternalLock() );
175 			// don't use the OContextEntryGuard - it will throw an exception if we're not alive
176 			// anymore, while the most recent specification for XComponent states that we should
177 			// silently ignore the call in such a situation
178 		if ( !isAlive() )
179 			return;
180 
181 		if ( _rxListener.is() )
182 		{
183 			sal_Int32 nListenerCount = AccessibleEventNotifier::removeEventListener( m_pImpl->getClientId( ), _rxListener );
184 			if ( !nListenerCount )
185 			{
186 				// no listeners anymore
187 				// -> revoke ourself. This may lead to the notifier thread dying (if we were the last client),
188 				// and at least to us not firing any events anymore, in case somebody calls
189 				// NotifyAccessibleEvent, again
190 				AccessibleEventNotifier::revokeClient( m_pImpl->getClientId( ) );
191 				m_pImpl->setClientId( 0 );
192 			}
193 		}
194 	}
195 
196 	//---------------------------------------------------------------------
197 	void SAL_CALL OAccessibleContextHelper::NotifyAccessibleEvent( const sal_Int16 _nEventId,
198 		const Any& _rOldValue, const Any& _rNewValue )
199 	{
200 		if ( !m_pImpl->getClientId( ) )
201 			// if we don't have a client id for the notifier, then we don't have listeners, then
202 			// we don't need to notify anything
203 			return;
204 
205 		// build an event object
206 		AccessibleEventObject aEvent;
207 		aEvent.Source = *this;
208 		aEvent.EventId = _nEventId;
209 		aEvent.OldValue = _rOldValue;
210 		aEvent.NewValue = _rNewValue;
211 
212 		// let the notifier handle this event
213 		AccessibleEventNotifier::addEvent( m_pImpl->getClientId( ), aEvent );
214 	}
215 
216 	//---------------------------------------------------------------------
217 	void SAL_CALL OAccessibleContextHelper::BufferAccessibleEvent( const sal_Int16 _nEventId,
218 		const Any& _rOldValue, const Any& _rNewValue,
219         AccessibleEventBuffer & _rBuffer )
220 	{
221 		// TODO: this whole method (as well as the class AccessibleEventBuffer) should be removed
222 		// The reasons why they have been introduces id that we needed to collect a set of events
223 		// before notifying them alltogether (after releasing our mutex). With the other
224 		// NotifyAccessibleEvent being asynchronous now, this should not be necessary anymore
225 		// - clients could use the other version now.
226 
227 		// copy our current listeners
228 		Sequence< Reference< XInterface > > aListeners;
229 		if ( m_pImpl->getClientId( ) )
230 			aListeners = AccessibleEventNotifier::getEventListeners( m_pImpl->getClientId( ) );
231 
232 		if ( aListeners.getLength() )
233 		{
234 			AccessibleEventObject aEvent;
235 			aEvent.Source = *this;
236 			OSL_ENSURE( aEvent.Source.is(), "OAccessibleContextHelper::BufferAccessibleEvent: invalid creator!" );
237 			aEvent.EventId = _nEventId;
238 			aEvent.OldValue = _rOldValue;
239 			aEvent.NewValue = _rNewValue;
240 
241             _rBuffer.addEvent( aEvent, aListeners );
242 		}
243 	}
244 
245 	//---------------------------------------------------------------------
246 	sal_Bool OAccessibleContextHelper::isAlive() const
247 	{
248 		return !GetBroadcastHelper().bDisposed && !GetBroadcastHelper().bInDispose;
249 	}
250 
251 	//---------------------------------------------------------------------
252 	void OAccessibleContextHelper::ensureAlive() const SAL_THROW( ( DisposedException ) )
253 	{
254 		if( !isAlive() )
255 			throw DisposedException();
256 	}
257 
258 	//---------------------------------------------------------------------
259 	void OAccessibleContextHelper::ensureDisposed( )
260 	{
261 		if ( !GetBroadcastHelper().bDisposed )
262 		{
263 			OSL_ENSURE( 0 == m_refCount, "OAccessibleContextHelper::ensureDisposed: this method _has_ to be called from without your dtor only!" );
264 			acquire();
265 			dispose();
266 		}
267 	}
268 
269 	//---------------------------------------------------------------------
270 	void OAccessibleContextHelper::lateInit( const Reference< XAccessible >& _rxAccessible )
271 	{
272 		m_pImpl->setCreator( _rxAccessible );
273 	}
274 
275 	//---------------------------------------------------------------------
276 	Reference< XAccessible > OAccessibleContextHelper::getAccessibleCreator( ) const
277 	{
278 		return m_pImpl->getCreator();
279 	}
280 
281 	//---------------------------------------------------------------------
282 	sal_Int32 SAL_CALL OAccessibleContextHelper::getAccessibleIndexInParent(  ) throw (RuntimeException)
283 	{
284 		OExternalLockGuard aGuard( this );
285 
286 		// -1 for child not found/no parent (according to specification)
287 		sal_Int32 nRet = -1;
288 
289 		try
290 		{
291 
292 			Reference< XAccessibleContext > xParentContext( implGetParentContext() );
293 
294 			//  iterate over parent's children and search for this object
295 			if ( xParentContext.is() )
296 			{
297 				// our own XAccessible for comparing with the children of our parent
298 				Reference< XAccessible > xCreator( m_pImpl->getCreator() );
299 
300 				OSL_ENSURE( xCreator.is(), "OAccessibleContextHelper::getAccessibleIndexInParent: invalid creator!" );
301 					// two ideas why this could be NULL:
302 					// * nobody called our late ctor (init), so we never had a creator at all -> bad
303 					// * the creator is already dead. In this case, we should have been disposed, and
304 					//	 never survived the above OContextEntryGuard.
305 					// in all other situations the creator should be non-NULL
306 
307 				if ( xCreator.is() )
308 				{
309 					sal_Int32 nChildCount = xParentContext->getAccessibleChildCount();
310 					for ( sal_Int32 nChild = 0; ( nChild < nChildCount ) && ( -1 == nRet ); ++nChild )
311 					{
312 						Reference< XAccessible > xChild( xParentContext->getAccessibleChild( nChild ) );
313 						if ( xChild.get() == xCreator.get() )
314 							nRet = nChild;
315 					}
316 				}
317 			}
318 		}
319 		catch( const Exception& )
320 		{
321 			OSL_ENSURE( sal_False, "OAccessibleContextHelper::getAccessibleIndexInParent: caught an exception!" );
322 		}
323 
324 		return nRet;
325 	}
326 
327 	//---------------------------------------------------------------------
328 	Locale SAL_CALL OAccessibleContextHelper::getLocale(  ) throw (IllegalAccessibleComponentStateException, RuntimeException)
329 	{
330 		// simply ask the parent
331 		Reference< XAccessible > xParent = getAccessibleParent();
332 		Reference< XAccessibleContext > xParentContext;
333 		if ( xParent.is() )
334 			xParentContext = xParent->getAccessibleContext();
335 
336 		if ( !xParentContext.is() )
337 			throw IllegalAccessibleComponentStateException( ::rtl::OUString(), *this );
338 
339 		return xParentContext->getLocale();
340 	}
341 
342 	//---------------------------------------------------------------------
343 	Reference< XAccessibleContext > OAccessibleContextHelper::implGetParentContext() SAL_THROW( ( RuntimeException ) )
344 	{
345 		Reference< XAccessible > xParent = getAccessibleParent();
346 		Reference< XAccessibleContext > xParentContext;
347 		if ( xParent.is() )
348 			xParentContext = xParent->getAccessibleContext();
349 		return xParentContext;
350 	}
351 
352 //.........................................................................
353 }	// namespace comphelper
354 //.........................................................................
355 
356 
357