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21 
22 
23 
24 #ifndef COMPHELPER_ACCIMPLACCESS_HXX
25 #define COMPHELPER_ACCIMPLACCESS_HXX
26 
27 #include <cppuhelper/implbase1.hxx>
28 #include <com/sun/star/lang/XUnoTunnel.hpp>
29 #include "comphelper/comphelperdllapi.h"
30 
31 // forward declaration
32 namespace com { namespace sun { namespace star { namespace accessibility {
33 	class XAccessible;
34 	class XAccessibleContext;
35 }}}}
36 
37 //.........................................................................
38 namespace comphelper
39 {
40 //.........................................................................
41 
42 	//=====================================================================
43 	//= OAccessibleImplementationAccess
44 	//=====================================================================
45 	typedef	::cppu::ImplHelper1	<	::com::sun::star::lang::XUnoTunnel
46 								>	OAccImpl_Base;
47 	struct OAccImpl_Impl;
48 
49 	/** This is a helper class which allows accessing several aspects of the the implementation
50 		of an AccessibleContext.
51 
52 		<p>For instance, when you want to implement a context which can be re-parented, you:
53 			<ul><li>derive your class from <type>OAccessibleImplementationAccess</type></li>
54 				<li>use <code>setAccessibleParent( <em>component</em>, <em>new_parent</em> )</code>
55 			</ul>
56 		</p>
57 
58 		<p>Another aspect which can be controlled from the outside are states. If you have a class which
59 		has only partial control over it's states, you may consider deriving from OAccessibleImplementationAccess.<br/>
60 		For instance, say you have an implementation (say component A) which is <em>unable</em> to know or to
61 		determine if the represented object is selected, but another component (say B) which uses A (and integrates
62 		it into a tree of accessibility components) is.<br/>
63 		In this case, if A is derived from OAccessibleImplementationAccess, B can manipulate this
64 		foreign-controlled state flag "SELECTED" by using the static helper methods on this class.</p>
65 
66 		<p>Please note that the support for foreign controlled states is rather restrictive: You can't have states
67 		which <em>may be</em> controlled by a foreign instances. This is implied by the fact that a derived
68 		class can ask for states which are <em>set</em> only, not for the ones which are <em>reset</em> currently.
69 		</p>
70 	*/
71 	class COMPHELPER_DLLPUBLIC OAccessibleImplementationAccess : public OAccImpl_Base
72 	{
73 	private:
74 		OAccImpl_Impl*	m_pImpl;
75 
76 	protected:
77 		/// retrieves the parent previously set via <method>setAccessibleParent</method>
78 		::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >
79 				implGetForeignControlledParent( ) const;
80 
81 		/** retrieves the set of currently set states which are controlled by a foreign instance
82 		@return
83 			a bit mask, where a set bit 2^n means that the AccessibleStateType n has been set
84 		*/
85 		sal_Int64	implGetForeignControlledStates( ) const;
86 
87 		/// sets the accessible parent component
88 		virtual	void	setAccessibleParent(
89 			const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& _rxAccParent );
90 
91 		/// sets or resets a bit of the foreign controlled states
92 		virtual	void	setStateBit( const sal_Int16 _nState, const sal_Bool _bSet );
93 
94 	protected:
95 		OAccessibleImplementationAccess( );
96 		virtual ~OAccessibleImplementationAccess( );
97 
98 		// XUnoTunnel
99 		virtual sal_Int64 SAL_CALL getSomething( const ::com::sun::star::uno::Sequence< sal_Int8 >& _rIdentifier ) throw (::com::sun::star::uno::RuntimeException);
100 
101 	public:
102 		/** tries to access the implementation of an OAccessibleImplementationAccess derivee which is known as
103 			interface only.
104 
105 		@param _rxComponent
106 			is the component which should be examined.
107 		@return
108 			the pointer to the implementation, if successfull. The only known error condition so far
109 			is an invalid context (which means it is <NULL/>, or the implementation is not derived
110 			from <type>OAccessibleImplementationAccess</type>, or retrieving the implementation failed).
111 		*/
112 		static OAccessibleImplementationAccess* getImplementation(
113 			const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent
114 		);
115 
116 
117 		/** sets the parent for a derived implementation
118 
119 		@param _rxComponent
120 			is the component which's new parent should be set
121 		@param _rxNewParent
122 			is the new parent of the component
123 		@return
124 			<TRUE/> in case of success, <FALSE/> otherwise. For error condition please look at
125 			<method>getImplementation</method>.
126 		*/
127 		static sal_Bool	setAccessibleParent(
128 			const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent,
129 			const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessible >& _rxNewParent
130 		);
131 
132 		/** sets or resets a state bit in the set of foreign-controlled states of the component.
133 
134 		@param _rxComponent
135 			is the component which's state is to be (re)set
136 		@param _nState
137 			the state bit which should be affected. This should be one of the respective UNO constants.
138 		@param _bSet
139 			<TRUE/> if the bit should be set, <FALSE/> otherwise
140 		@return
141 			<TRUE/> in case of success, <FALSE/> otherwise. For error condition please look at
142 			<method>getImplementation</method>.
143 		*/
144 		static sal_Bool	setForeignControlledState(
145 			const ::com::sun::star::uno::Reference< ::com::sun::star::accessibility::XAccessibleContext >& _rxComponent,
146 			const sal_Int16 _nState,
147 			const sal_Bool	_bSet
148 		);
149 
150 
151 	private:
152 		COMPHELPER_DLLPRIVATE static const ::com::sun::star::uno::Sequence< sal_Int8 >& getUnoTunnelImplementationId();
153 	};
154 
155 //.........................................................................
156 }	// namespace comphelper
157 //.........................................................................
158 
159 
160 #endif // COMPHELPER_ACCIMPLACCESS_HXX
161 
162 
163