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 #include <memory>
  27
  28 namespace com { namespace sun { namespace star { namespace accessibility {
  29     class XAccessible;
  30     class XAccessibleContext;
  31 }}}}
  32
  33 namespace comphelper
  34 {
  35     //= OAccessibleImplementationAccess
  36
  37     typedef ::cppu::ImplHelper1 <   css::lang::XUnoTunnel
  38                                 >   OAccImpl_Base;
  39     struct OAccImpl_Impl;
  40
  41     /** This is a helper class which allows accessing several aspects of the implementation
  42         of an AccessibleContext.
  43
  44         <p>For instance, when you want to implement a context which can be re-parented, you:
  45             <ul><li>derive your class from OAccessibleImplementationAccess</li>
  46                 <li>use <code>setAccessibleParent( <em>component</em>, <em>new_parent</em> )</code>
  47             </ul>
  48         </p>
  49
  50         <p>Another aspect which can be controlled from the outside are states. If you have a class which
  51         has only partial control over it's states, you may consider deriving from OAccessibleImplementationAccess.<br/>
  52         For instance, say you have an implementation (say component A) which is <em>unable</em> to know or to
  53         determine if the represented object is selected, but another component (say B) which uses A (and integrates
  54         it into a tree of accessibility components) is.<br/>
  55         In this case, if A is derived from OAccessibleImplementationAccess, B can manipulate this
  56         foreign-controlled state flag "SELECTED" by using the static helper methods on this class.</p>
  57
  58         <p>Please note that the support for foreign controlled states is rather restrictive: You can't have states
  59         which <em>may be</em> controlled by a foreign instances. This is implied by the fact that a derived
  60         class can ask for states which are <em>set</em> only, not for the ones which are <em>reset</em> currently.
  61         </p>
  62     */
  63     class COMPHELPER_DLLPUBLIC OAccessibleImplementationAccess : public OAccImpl_Base
  64     {
  65     private:
  66         std::unique_ptr<OAccImpl_Impl>  m_pImpl;
  67
  68     protected:
  69         /// retrieves the parent previously set via <method>setAccessibleParent</method>
  70         const css::uno::Reference< css::accessibility::XAccessible >&
  71                 implGetForeignControlledParent( ) const;
  72
  73         /** retrieves the set of currently set states which are controlled by a foreign instance
  74         @return
  75             a bit mask, where a set bit 2^n means that the AccessibleStateType n has been set
  76         */
  77         sal_Int64   implGetForeignControlledStates( ) const;
  78
  79     protected:
  80         OAccessibleImplementationAccess( );
  81         virtual ~OAccessibleImplementationAccess( );
  82
  83         // XUnoTunnel
  84         virtual sal_Int64 SAL_CALL getSomething( const css::uno::Sequence< sal_Int8 >& _rIdentifier ) override;
  85
  86     public:
  87
  88     private:
  89         COMPHELPER_DLLPRIVATE static const css::uno::Sequence< sal_Int8 > getUnoTunnelImplementationId();
  90     };
  91
  92 } // namespace comphelper
  93
  94 #endif // INCLUDED_COMPHELPER_ACCIMPLACCESS_HXX
  95
  96 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */