accessiblecontexthelper.cxx

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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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 *   Licensed to the Apache Software Foundation (ASF) under one or more
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#include <comphelper/accessiblecontexthelper.hxx>
#include <osl/diagnose.h>
#include <cppuhelper/weakref.hxx>
#include <com/sun/star/accessibility/IllegalAccessibleComponentStateException.hpp>
#include <comphelper/accessibleeventnotifier.hxx>
#include <comphelper/solarmutex.hxx>
 
 
namespace comphelper
{
    using namespace ::com::sun::star::uno;
    using namespace ::com::sun::star::lang;
    using namespace ::com::sun::star::accessibility;
 
    OAccessibleContextHelper::OAccessibleContextHelper( )
        :OAccessibleContextHelper_Base( GetMutex() )
        ,m_nClientId( 0 )
    {
    }
 
 
    OAccessibleContextHelper::~OAccessibleContextHelper( )
    {
            // this ensures that the lock, which may be already destroyed as part of the derivee,
            // is not used anymore
 
        ensureDisposed();
    }
 
 
    void SAL_CALL OAccessibleContextHelper::disposing()
    {
        // rhbz#1001768: de facto this class is locked by SolarMutex;
        // do not lock m_Mutex because it may cause deadlock
        osl::Guard<SolarMutex> aGuard(SolarMutex::get());
 
        if ( m_nClientId )
        {
            AccessibleEventNotifier::revokeClientNotifyDisposing( m_nClientId, *this );
            m_nClientId=0;
        }
    }
 
 
    void SAL_CALL OAccessibleContextHelper::addAccessibleEventListener( const Reference< XAccessibleEventListener >& _rxListener )
    {
        osl::Guard<SolarMutex> aGuard(SolarMutex::get());
            // don't use the OContextEntryGuard - it will throw an exception if we're not alive
            // anymore, while the most recent specification for XComponent states that we should
            // silently ignore the call in such a situation
        if ( !isAlive() )
        {
            if ( _rxListener.is() )
                _rxListener->disposing( EventObject( *this ) );
            return;
        }
 
        if ( _rxListener.is() )
        {
            if ( !m_nClientId )
                m_nClientId = AccessibleEventNotifier::registerClient( );
 
            AccessibleEventNotifier::addEventListener( m_nClientId, _rxListener );
        }
    }
 
 
    void SAL_CALL OAccessibleContextHelper::removeAccessibleEventListener( const Reference< XAccessibleEventListener >& _rxListener )
    {
        osl::Guard<SolarMutex> aGuard(SolarMutex::get());
            // don't use the OContextEntryGuard - it will throw an exception if we're not alive
            // anymore, while the most recent specification for XComponent states that we should
            // silently ignore the call in such a situation
        if ( !isAlive() )
            return;
 
        if ( !(_rxListener.is() && m_nClientId) )
            return;
 
        sal_Int32 nListenerCount = AccessibleEventNotifier::removeEventListener( m_nClientId, _rxListener );
        if ( !nListenerCount )
        {
            // no listeners anymore
            // -> revoke ourself. This may lead to the notifier thread dying (if we were the last client),
            // and at least to us not firing any events anymore, in case somebody calls
            // NotifyAccessibleEvent, again
            AccessibleEventNotifier::revokeClient( m_nClientId );
            m_nClientId = 0;
        }
    }
 
 
    void OAccessibleContextHelper::NotifyAccessibleEvent( const sal_Int16 _nEventId,
        const Any& _rOldValue, const Any& _rNewValue )
    {
        if ( !m_nClientId )
            // if we don't have a client id for the notifier, then we don't have listeners, then
            // we don't need to notify anything
            return;
 
        // build an event object
        AccessibleEventObject aEvent;
        aEvent.Source = *this;
        aEvent.EventId = _nEventId;
        aEvent.OldValue = _rOldValue;
        aEvent.NewValue = _rNewValue;
 
        // let the notifier handle this event
        AccessibleEventNotifier::addEvent( m_nClientId, aEvent );
    }
 
 
    bool OAccessibleContextHelper::isAlive() const
    {
        return !rBHelper.bDisposed && !rBHelper.bInDispose;
    }
 
 
    void OAccessibleContextHelper::ensureAlive() const
    {
        if( !isAlive() )
            throw DisposedException();
    }
 
 
    void OAccessibleContextHelper::ensureDisposed( )
    {
        if ( !rBHelper.bDisposed )
        {
            OSL_ENSURE( 0 == m_refCount, "OAccessibleContextHelper::ensureDisposed: this method _has_ to be called from without your dtor only!" );
            acquire();
            dispose();
        }
    }
 
 
    void OAccessibleContextHelper::lateInit( const Reference< XAccessible >& _rxAccessible )
    {
        m_aCreator = _rxAccessible;
    }
 
 
    Reference< XAccessible > OAccessibleContextHelper::getAccessibleCreator( ) const
    {
        return m_aCreator;
    }
 
 
    OUString SAL_CALL OAccessibleContextHelper::getAccessibleId(  )
    {
        return OUString();
    }
 
 
    sal_Int64 SAL_CALL OAccessibleContextHelper::getAccessibleIndexInParent(  )
    {
        OExternalLockGuard aGuard( this );
 
        // -1 for child not found/no parent (according to specification)
        sal_Int64 nRet = -1;
 
        try
        {
 
            Reference< XAccessibleContext > xParentContext( implGetParentContext() );
 
            //  iterate over parent's children and search for this object
            if ( xParentContext.is() )
            {
                // our own XAccessible for comparing with the children of our parent
                Reference< XAccessible > xCreator( m_aCreator);
 
                OSL_ENSURE( xCreator.is(), "OAccessibleContextHelper::getAccessibleIndexInParent: invalid creator!" );
                    // two ideas why this could be NULL:
                    // * nobody called our late ctor (init), so we never had a creator at all -> bad
                    // * the creator is already dead. In this case, we should have been disposed, and
                    //   never survived the above OContextEntryGuard.
                    // in all other situations the creator should be non-NULL
 
                if ( xCreator.is() )
                {
                    sal_Int64 nChildCount = xParentContext->getAccessibleChildCount();
                    for ( sal_Int64 nChild = 0; ( nChild < nChildCount ) && ( -1 == nRet ); ++nChild )
                    {
                        Reference< XAccessible > xChild( xParentContext->getAccessibleChild( nChild ) );
                        if ( xChild.get() == xCreator.get() )
                            nRet = nChild;
                    }
                }
            }
        }
        catch( const Exception& )
        {
            OSL_FAIL( "OAccessibleContextHelper::getAccessibleIndexInParent: caught an exception!" );
        }
 
        return nRet;
    }
 
 
    Locale SAL_CALL OAccessibleContextHelper::getLocale(  )
    {
        // simply ask the parent
        Reference< XAccessible > xParent = getAccessibleParent();
        Reference< XAccessibleContext > xParentContext;
        if ( xParent.is() )
            xParentContext = xParent->getAccessibleContext();
 
        if ( !xParentContext.is() )
            throw IllegalAccessibleComponentStateException( OUString(), *this );
 
        return xParentContext->getLocale();
    }
 
 
    Reference< XAccessibleContext > OAccessibleContextHelper::implGetParentContext()
    {
        Reference< XAccessible > xParent = getAccessibleParent();
        Reference< XAccessibleContext > xParentContext;
        if ( xParent.is() )
            xParentContext = xParent->getAccessibleContext();
        return xParentContext;
    }
 
 
}   // namespace comphelper
 
 
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