include/comphelper/accimplaccess.hxx

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  19
  20 #ifndef INCLUDED_COMPHELPER_ACCIMPLACCESS_HXX
  21 #define INCLUDED_COMPHELPER_ACCIMPLACCESS_HXX
  22
  23 #include <cppuhelper/implbase1.hxx>
  24 #include <com/sun/star/lang/XUnoTunnel.hpp>
  25 #include <comphelper/comphelperdllapi.h>
  26
  27 namespace com { namespace sun { namespace star { namespace accessibility {
  28     class XAccessible;
  29     class XAccessibleContext;
  30 }}}}
  31
  32 namespace comphelper
  33 {
  34     //= OAccessibleImplementationAccess
  35
  36     typedef ::cppu::ImplHelper1 <   ::com::sun::star::lang::XUnoTunnel
  37                                 >   OAccImpl_Base;
  38     struct OAccImpl_Impl;
  39
  40     /** This is a helper class which allows accessing several aspects of the implementation
  41         of an AccessibleContext.
  42
  43         <p>For instance, when you want to implement a context which can be re-parented, you:
  44             <ul><li>derive your class from OAccessibleImplementationAccess</li>
  45                 <li>use <code>setAccessibleParent( <em>component</em>, <em>new_parent</em> )</code>
  46             </ul>
  47         </p>
  48
  49         <p>Another aspect which can be controlled from the outside are states. If you have a class which
  50         has only partial control over it's states, you may consider deriving from OAccessibleImplementationAccess.<br/>
  51         For instance, say you have an implementation (say component A) which is <em>unable</em> to know or to
  52         determine if the represented object is selected, but another component (say B) which uses A (and integrates
  53         it into a tree of accessibility components) is.<br/>
  54         In this case, if A is derived from OAccessibleImplementationAccess, B can manipulate this
  55         foreign-controlled state flag "SELECTED" by using the static helper methods on this class.</p>
  56
  57         <p>Please note that the support for foreign controlled states is rather restrictive: You can't have states
  58         which <em>may be</em> controlled by a foreign instances. This is implied by the fact that a derived
  59         class can ask for states which are <em>set</em> only, not for the ones which are <em>reset</em> currently.
  60         </p>
  61     */
  62     class COMPHELPER_DLLPUBLIC OAccessibleImplementationAccess : public OAccImpl_Base
  63     {
  64     private:
  65         OAccImpl_Impl*  m_pImpl;
  66
  67     protected:
  68         /// retrieves the parent previously set via <method>setAccessibleParent</method>
  69         ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
  70                 implGetForeignControlledParent( ) const;
  71
  72         /** retrieves the set of currently set states which are controlled by a foreign instance
  73         @return
  74             a bit mask, where a set bit 2^n means that the AccessibleStateType n has been set
  75         */
  76         sal_Int64   implGetForeignControlledStates( ) const;
  77
  78         /// sets the accessible parent component
  79         void setAccessibleParent(
  80             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& _rxAccParent );
  81
  82         /// sets or resets a bit of the foreign controlled states
  83         void setStateBit( const sal_Int16 _nState, const bool _bSet );
  84
  85     protected:
  86         OAccessibleImplementationAccess( );
  87         virtual ~OAccessibleImplementationAccess( );
  88
  89         // XUnoTunnel
  90         virtual sal_Int64 SAL_CALL getSomething( const ::com::sun::star::uno::Sequence< sal_Int8 >& _rIdentifier ) throw (::com::sun::star::uno::RuntimeException, std::exception) SAL_OVERRIDE;
  91
  92     public:
  93         /** tries to access the implementation of an OAccessibleImplementationAccess derivee which is known as
  94             interface only.
  95
  96         @param _rxComponent
  97             is the component which should be examined.
  98         @return
  99             the pointer to the implementation, if successful. The only known error condition so far
 100             is an invalid context (which means it is <NULL/>, or the implementation is not derived
 101             from OAccessibleImplementationAccess, or retrieving the implementation failed).
 102         */
 103         static OAccessibleImplementationAccess* getImplementation(
 104             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent
 105         );
 106
 107         /** sets the parent for a derived implementation
 108
 109         @param _rxComponent
 110             is the component which's new parent should be set
 111         @param _rxNewParent
 112             is the new parent of the component
 113         @return
 114             <TRUE/> in case of success, <FALSE/> otherwise. For error condition please look at
 115             <method>getImplementation</method>.
 116         */
 117         static bool setAccessibleParent(
 118             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent,
 119             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& _rxNewParent
 120         );
 121
 122     private:
 123         COMPHELPER_DLLPRIVATE static const ::com::sun::star::uno::Sequence< sal_Int8 > getUnoTunnelImplementationId();
 124     };
 125
 126 } // namespace comphelper
 127
 128 #endif // INCLUDED_COMPHELPER_ACCIMPLACCESS_HXX
 129
 130 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */