accessiblecontexthelper.hxx

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#ifndef INCLUDED_COMPHELPER_ACCESSIBLECONTEXTHELPER_HXX
#define INCLUDED_COMPHELPER_ACCESSIBLECONTEXTHELPER_HXX

#include <cppuhelper/compbase2.hxx>
#include <cppuhelper/basemutex.hxx>
#include <com/sun/star/accessibility/XAccessibleContext2.hpp>
#include <com/sun/star/accessibility/XAccessibleEventBroadcaster.hpp>
#include <comphelper/accessibleeventnotifier.hxx>
#include <comphelper/comphelperdllapi.h>
#include <comphelper/solarmutex.hxx>


namespace comphelper
{


    //= OAccessibleContextHelper


    typedef ::cppu::WeakAggComponentImplHelper2 <   css::accessibility::XAccessibleContext2,
                                                    css::accessibility::XAccessibleEventBroadcaster
                                                >   OAccessibleContextHelper_Base;

    class COMPHELPER_DLLPUBLIC OAccessibleContextHelper
                :public ::cppu::BaseMutex
                ,public OAccessibleContextHelper_Base
    {
        friend class OContextEntryGuard;
    private:
        css::uno::WeakReference< css::accessibility::XAccessible > m_aCreator;         // the XAccessible which created our XAccessibleContext
        AccessibleEventNotifier::TClientId m_nClientId;

    protected:
        virtual ~OAccessibleContextHelper( ) override;

        OAccessibleContextHelper( );

        void    lateInit( const css::uno::Reference< css::accessibility::XAccessible >& _rxAccessible );

        css::uno::Reference< css::accessibility::XAccessible >
                getAccessibleCreator( ) const;

    public:
        // XAccessibleEventBroadcaster
        virtual void SAL_CALL addAccessibleEventListener( const css::uno::Reference< css::accessibility::XAccessibleEventListener >& xListener ) override;
        virtual void SAL_CALL removeAccessibleEventListener( const css::uno::Reference< css::accessibility::XAccessibleEventListener >& xListener ) override;

        // XAccessibleContext - still waiting to be overwritten
        virtual sal_Int32 SAL_CALL getAccessibleChildCount(  ) override = 0;
        virtual css::uno::Reference< css::accessibility::XAccessible > SAL_CALL getAccessibleChild( sal_Int32 i ) override = 0;
        virtual css::uno::Reference< css::accessibility::XAccessible > SAL_CALL getAccessibleParent(  ) override = 0;
        virtual sal_Int16 SAL_CALL getAccessibleRole(  ) override = 0;
        virtual OUString SAL_CALL getAccessibleDescription(  ) override = 0;
        virtual OUString SAL_CALL getAccessibleName(  ) override = 0;
        virtual css::uno::Reference< css::accessibility::XAccessibleRelationSet > SAL_CALL getAccessibleRelationSet(  ) override = 0;
        virtual css::uno::Reference< css::accessibility::XAccessibleStateSet > SAL_CALL getAccessibleStateSet(  ) override = 0;

        // XAccessibleContext2 - default implementation
        virtual OUString SAL_CALL getAccessibleId(  ) override;

        // XAccessibleContext - default implementations
        virtual sal_Int32 SAL_CALL getAccessibleIndexInParent(  ) override;
        virtual css::lang::Locale SAL_CALL getLocale(  ) override;

    protected:
        // OComponentHelper
        virtual void SAL_CALL disposing() override;

    protected:
        // helper
        void NotifyAccessibleEvent(
                    const sal_Int16 _nEventId,
                    const css::uno::Any& _rOldValue,
                    const css::uno::Any& _rNewValue
                );

        // life time control
        bool    isAlive() const;
        void        ensureAlive() const;

        void        ensureDisposed( );

        css::uno::Reference< css::accessibility::XAccessibleContext >
                    implGetParentContext();

        // access to the base class' broadcast helper/mutex
        ::osl::Mutex&                   GetMutex()                  { return m_aMutex; }
    };


    //= OContextEntryGuard

    class OContextEntryGuard : public ::osl::ClearableMutexGuard
    {
    public:
        inline OContextEntryGuard( OAccessibleContextHelper* _pContext );
    };


    inline OContextEntryGuard::OContextEntryGuard( OAccessibleContextHelper* _pContext  )
        : ::osl::ClearableMutexGuard( _pContext->GetMutex() )
    {
        _pContext->ensureAlive();
    }


    //= OExternalLockGuard

    class OExternalLockGuard
            :public osl::Guard<SolarMutex>
            ,public OContextEntryGuard
    {
    public:
        inline OExternalLockGuard( OAccessibleContextHelper* _pContext );
    };


    inline OExternalLockGuard::OExternalLockGuard( OAccessibleContextHelper* _pContext )
        :osl::Guard<SolarMutex>( SolarMutex::get() )
        ,OContextEntryGuard( _pContext )
    {
        // Only lock the external mutex,
        // release the ::osl::Mutex of the OAccessibleContextHelper instance.
        // If you call into another UNO object with locked ::osl::Mutex,
        // this may lead to dead locks.
        clear();
    }


}   // namespace comphelper


#endif // INCLUDED_COMPHELPER_ACCESSIBLECONTEXTHELPER_HXX


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