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 // forward declaration
  28 namespace com { namespace sun { namespace star { namespace accessibility {
  29     class XAccessible;
  30     class XAccessibleContext;
  31 }}}}
  32
  33 //.........................................................................
  34 namespace comphelper
  35 {
  36 //.........................................................................
  37
  38     //=====================================================================
  39     //= OAccessibleImplementationAccess
  40     //=====================================================================
  41     typedef ::cppu::ImplHelper1 <   ::com::sun::star::lang::XUnoTunnel
  42                                 >   OAccImpl_Base;
  43     struct OAccImpl_Impl;
  44
  45     /** This is a helper class which allows accessing several aspects of the implementation
  46         of an AccessibleContext.
  47
  48         <p>For instance, when you want to implement a context which can be re-parented, you:
  49             <ul><li>derive your class from OAccessibleImplementationAccess</li>
  50                 <li>use <code>setAccessibleParent( <em>component</em>, <em>new_parent</em> )</code>
  51             </ul>
  52         </p>
  53
  54         <p>Another aspect which can be controlled from the outside are states. If you have a class which
  55         has only partial control over it's states, you may consider deriving from OAccessibleImplementationAccess.<br/>
  56         For instance, say you have an implementation (say component A) which is <em>unable</em> to know or to
  57         determine if the represented object is selected, but another component (say B) which uses A (and integrates
  58         it into a tree of accessibility components) is.<br/>
  59         In this case, if A is derived from OAccessibleImplementationAccess, B can manipulate this
  60         foreign-controlled state flag "SELECTED" by using the static helper methods on this class.</p>
  61
  62         <p>Please note that the support for foreign controlled states is rather restrictive: You can't have states
  63         which <em>may be</em> controlled by a foreign instances. This is implied by the fact that a derived
  64         class can ask for states which are <em>set</em> only, not for the ones which are <em>reset</em> currently.
  65         </p>
  66     */
  67     class COMPHELPER_DLLPUBLIC OAccessibleImplementationAccess : public OAccImpl_Base
  68     {
  69     private:
  70         OAccImpl_Impl*  m_pImpl;
  71
  72     protected:
  73         /// retrieves the parent previously set via <method>setAccessibleParent</method>
  74         ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
  75                 implGetForeignControlledParent( ) const;
  76
  77         /** retrieves the set of currently set states which are controlled by a foreign instance
  78         @return
  79             a bit mask, where a set bit 2^n means that the AccessibleStateType n has been set
  80         */
  81         sal_Int64   implGetForeignControlledStates( ) const;
  82
  83         /// sets the accessible parent component
  84         virtual void    setAccessibleParent(
  85             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& _rxAccParent );
  86
  87         /// sets or resets a bit of the foreign controlled states
  88         virtual void    setStateBit( const sal_Int16 _nState, const sal_Bool _bSet );
  89
  90     protected:
  91         OAccessibleImplementationAccess( );
  92         virtual ~OAccessibleImplementationAccess( );
  93
  94         // XUnoTunnel
  95         virtual sal_Int64 SAL_CALL getSomething( const ::com::sun::star::uno::Sequence< sal_Int8 >& _rIdentifier ) throw (::com::sun::star::uno::RuntimeException);
  96
  97     public:
  98         /** tries to access the implementation of an OAccessibleImplementationAccess derivee which is known as
  99             interface only.
 100
 101         @param _rxComponent
 102             is the component which should be examined.
 103         @return
 104             the pointer to the implementation, if successful. The only known error condition so far
 105             is an invalid context (which means it is <NULL/>, or the implementation is not derived
 106             from OAccessibleImplementationAccess, or retrieving the implementation failed).
 107         */
 108         static OAccessibleImplementationAccess* getImplementation(
 109             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent
 110         );
 111
 112
 113         /** sets the parent for a derived implementation
 114
 115         @param _rxComponent
 116             is the component which's new parent should be set
 117         @param _rxNewParent
 118             is the new parent of the component
 119         @return
 120             <TRUE/> in case of success, <FALSE/> otherwise. For error condition please look at
 121             <method>getImplementation</method>.
 122         */
 123         static sal_Bool setAccessibleParent(
 124             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent,
 125             const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& _rxNewParent
 126         );
 127
 128
 129     private:
 130         COMPHELPER_DLLPRIVATE static const ::com::sun::star::uno::Sequence< sal_Int8 > getUnoTunnelImplementationId();
 131     };
 132
 133 //.........................................................................
 134 }   // namespace comphelper
 135 //.........................................................................
 136
 137
 138 #endif // INCLUDED_COMPHELPER_ACCIMPLACCESS_HXX
 139
 140
 141 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */