xref: /trunk/main/comphelper/inc/comphelper/accessibleeventnotifier.hxx (revision 9877b273)

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 * Licensed to the Apache Software Foundation (ASF) under one
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 * to you under the Apache License, Version 2.0 (the
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#ifndef COMPHELPER_ACCESSIBLE_EVENT_NOTIFIER
#define COMPHELPER_ACCESSIBLE_EVENT_NOTIFIER

#include <com/sun/star/accessibility/AccessibleEventObject.hpp>
#include <com/sun/star/accessibility/XAccessibleEventListener.hpp>
#include <osl/thread.hxx>
#include <osl/conditn.hxx>
#include <cppuhelper/interfacecontainer.h>
#include "comphelper/comphelperdllapi.h"

#include <map>
#include <list>

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

	//=====================================================================
	//= AccessibleEventNotifier
	//=====================================================================
	class COMPHELPER_DLLPUBLIC AccessibleEventNotifier
	{
	// typedefs
	public:
		typedef sal_uInt32	TClientId;

		typedef ::std::pair< TClientId, ::com::sun::star::accessibility::AccessibleEventObject >
																					ClientEvent;

		typedef ::cppu::OInterfaceContainerHelper									EventListeners;
		typedef ::std::map< TClientId, EventListeners*, ::std::less< TClientId > >	ClientMap;

	protected:
		AccessibleEventNotifier( );		// never implemented
		~AccessibleEventNotifier( );	// never implemented

	private:
		COMPHELPER_DLLPRIVATE AccessibleEventNotifier( const AccessibleEventNotifier& );				// never implemented!
		COMPHELPER_DLLPRIVATE AccessibleEventNotifier& operator=( const AccessibleEventNotifier& );	// never implemented!

	public:
		/** registers a client of this class, means a broadcaster of AccessibleEvents

			<p>No precaution is taken to care for disposal of this component. When the component
			dies, it <b>must</b> call <member>revokeClient</member> or <member>revokeClientNotifyDisposing</member>
			explicitly itself.</p>
		*/
		static	TClientId	registerClient( );

		/** revokes a broadcaster of AccessibleEvents

			<p>Note that no disposing event is fired when you use this method, the client is simply revoked.
			You can for instance revoke a client if the last listener for it is revoked, but the client
			itself is not disposed.<br/>
			When the client is disposed, you should prefer <member>revokeClientNotifyDisposing</member></p>

			<p>Any possibly pending events for this client are removed from the queue.</p>

			@seealso revokeClientNotifyDisposing
		*/
		static	void		revokeClient( const TClientId _nClient );

		/** revokes a client, with additionally notifying a disposing event to all listeners registered for
			this client

			<p>Any other possibly pending events for this client are removed from the queue</p>

			@param _nClient
				the id of the client which should be revoked
			@param _rxEventSource
				the source to be notified together with the <member scope="com.sun.star.lang">XComponent::disposing</member>
				call.
		*/
		static	void		revokeClientNotifyDisposing(
						const TClientId _nClient,
						const ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface >& _rxEventSource
					) SAL_THROW( ( ) );

		/** registers a listener for the given client

			@param _nClient
				the id of the client for which a listener should be registered
			@return
				the number of event listeners currently registered for this client
		*/
		static sal_Int32 addEventListener(
						const TClientId _nClient,
						const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleEventListener >& _rxListener
					) SAL_THROW( ( ) );

		/** revokes a listener for the given client

			@param _nClient
				the id of the client for which a listener should be revoked
			@return
				the number of event listeners currently registered for this client
		*/
		static sal_Int32 removeEventListener(
						const TClientId _nClient,
						const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleEventListener >& _rxListener
					) SAL_THROW( ( ) );

		/** retrieves the set of listeners registered for a given client
		*/
		static ::com::sun::star::uno::Sequence< ::com::sun::star::uno::Reference< ::com::sun::star::uno::XInterface > >
						getEventListeners( const TClientId _nClient ) SAL_THROW( ( ) );

		/** adds an event, which is to be braodcasted, to the queue

			@param _nClient
				the id of the client which needs to broadcast the event
		*/
		static void	addEvent(
						const TClientId _nClient,
						const ::com::sun::star::accessibility::AccessibleEventObject& _rEvent
					) SAL_THROW( ( ) );

	private:
		/// generates a new client id
		COMPHELPER_DLLPRIVATE static	TClientId	generateId();

		/** looks up a client in our client map, asserts if it cannot find it or no event thread is present

			@precond
				to be called with our mutex locked

			@param _nClient
				the id of the client to loopup
			@param _rPos
				out-parameter for the position of the client in the client map

			@return
				<TRUE/> if and only if the client could be found and <arg>_rPos</arg> has been filled with
				it's position
		*/
		COMPHELPER_DLLPRIVATE static	sal_Bool	implLookupClient( const TClientId _nClient, ClientMap::iterator& _rPos );
	};

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

#endif // COMPHELPER_ACCESSIBLE_EVENT_NOTIFIER