AOO410/main/comphelper/inc/comphelper/weakeventlistener.hxx

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#ifndef COMPHELPER_WEAKEVENTLISTENER_HXX
#define COMPHELPER_WEAKEVENTLISTENER_HXX

#include <cppuhelper/compbase1.hxx>
#include <com/sun/star/lang/XComponent.hpp>
#include <com/sun/star/uno/XWeak.hpp>
#include <cppuhelper/weakref.hxx>
#include <comphelper/broadcasthelper.hxx>
#include "comphelper/comphelperdllapi.h"

//.........................................................................
namespace comphelper
{
//.........................................................................

	//=====================================================================
	//= OWeakListenerAdapterBase
	//=====================================================================
	/** (the base for) an adapter which allows to add as listener to a foreign component, without
		being held hard.

		<p>The idea is that this adapter is added as listener to a foreign component, which usually
		holds it's listener hard. The adapter itself knows the real listener as weak reference,
		thus not affecting it's life time.</p>
	*/
	class OWeakListenerAdapterBase : public OBaseMutex
	{
	private:
		::com::sun::star::uno::WeakReference< ::com::sun::star::uno::XInterface >
				m_aListener;
		::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >
				m_xBroadcaster;

	protected:
		inline ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >
				getListener( ) const
		{
			return m_aListener.get();
		}

		inline const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >&
				getBroadcaster( ) const
		{
			return m_xBroadcaster;
		}

		inline void resetListener( )
		{
            m_aListener.clear();
		}


	protected:
		inline 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
		)
			:m_aListener	(  _rxListener )
			,m_xBroadcaster	( _rxBroadcaster )
		{
		}

	protected:
		virtual	~OWeakListenerAdapterBase();
	};


	//=====================================================================
	//= OWeakListenerAdapter
	//=====================================================================
	template< class BROADCASTER, class LISTENER >
	/** yet another base for weak listener adapters, this time with some type safety

		<p>Note that derived classes need to overwrite all virtual methods of their interface
		except XEventListener::disposing, and forward it to their master listener.</p>

		<p>Addtionally, derived classes need to add themself as listener to the broadcaster,
		as this can't be done in a generic way</p>
	*/
	class OWeakListenerAdapter
			:public ::cppu::WeakComponentImplHelper1 < LISTENER >
			,public OWeakListenerAdapterBase
	{
	protected:
		/** ctor
			<p>Note that derived classes still need to add themself as listener to the broadcaster,
			as this can't be done in a generic way</p>
		*/
		OWeakListenerAdapter(
			const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak >& _rxListener,
			const ::com::sun::star::uno::Reference< BROADCASTER >& _rxBroadcaster
		);

	protected:
		inline	::com::sun::star::uno::Reference< LISTENER > getListener( ) const
		{
			return	::com::sun::star::uno::Reference< LISTENER >( OWeakListenerAdapterBase::getListener(), ::com::sun::star::uno::UNO_QUERY );
		}

		// XEventListener overridables
		virtual void SAL_CALL disposing( const ::com::sun::star::lang::EventObject& Source ) throw (::com::sun::star::uno::RuntimeException);

	protected:
		// OComponentHelper overridables
		// to be overridden, again - the derived class should revoke the listener from the broadcaster
		virtual void SAL_CALL disposing( ) = 0;
	};

	//=====================================================================
	//= OWeakEventListenerAdapter
	//=====================================================================
	typedef OWeakListenerAdapter	<	::com::sun::star::lang::XComponent
									,	::com::sun::star::lang::XEventListener
									>	OWeakEventListenerAdapter_Base;
	/**	the most simple listener adapter: for XEventListeners at XComponents
	*/
	class COMPHELPER_DLLPUBLIC OWeakEventListenerAdapter : public OWeakEventListenerAdapter_Base
	{
	public:
		OWeakEventListenerAdapter(
			::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak > _rxListener,
			::com::sun::star::uno::Reference< ::com::sun::star::lang::XComponent > _rxBroadcaster
		);

		// nothing to do except an own ctor - the forwarding of the "disposing" is already done
		// in the base class

	protected:
        using OWeakEventListenerAdapter_Base::disposing;
		virtual void SAL_CALL disposing( );
	};

	//=====================================================================
	//= OWeakListenerAdapter
	//=====================================================================
	//---------------------------------------------------------------------
	template< class BROADCASTER, class LISTENER >
	OWeakListenerAdapter< BROADCASTER, LISTENER >::OWeakListenerAdapter(
		const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XWeak >& _rxListener,
		const ::com::sun::star::uno::Reference< BROADCASTER >& _rxBroadcaster
	)
		: ::cppu::WeakComponentImplHelper1< LISTENER >( m_aMutex )
		, OWeakListenerAdapterBase( _rxListener, _rxBroadcaster )
	{
	}

	//---------------------------------------------------------------------
	template< class BROADCASTER, class LISTENER >
	void SAL_CALL OWeakListenerAdapter< BROADCASTER, LISTENER >::disposing( const ::com::sun::star::lang::EventObject& _rSource ) throw (::com::sun::star::uno::RuntimeException)
	{
		::com::sun::star::uno::Reference< LISTENER > xListener( getListener() );
		if ( xListener.is() )
			xListener->disposing( _rSource );
	}

//.........................................................................
}	// namespace comphelper
//.........................................................................

#endif// COMPHELPER_WEAKEVENTLISTENER_HXX