include/svx/ShapeTypeHandler.hxx

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  19
  20 #ifndef INCLUDED_SVX_SHAPETYPEHANDLER_HXX
  21 #define INCLUDED_SVX_SHAPETYPEHANDLER_HXX
  22
  23 #include <svx/svxdllapi.h>
  24
  25 #include <rtl/ref.hxx>
  26 #include <rtl/ustring.hxx>
  27 #include <tools/long.hxx>
  28 #include <unordered_map>
  29 #include <utility>
  30 #include <vector>
  31
  32 namespace accessibility { class AccessibleShape; }
  33 namespace accessibility { class AccessibleShapeInfo; }
  34 namespace accessibility { class AccessibleShapeTreeInfo; }
  35 namespace com::sun::star::drawing { class XShape; }
  36 namespace com::sun::star::uno { template <typename > class Reference; }
  37
  38 namespace accessibility {
  39
  40 /** Use an integer to represent shape type ids.  A ShapeTypeId is unique
  41     inside one project but is not over the project boundaries.
  42 */
  43 typedef int ShapeTypeId;
  44
  45 /** Define the function type for creating accessible objects for given
  46     service names.
  47 */
  48 typedef rtl::Reference<AccessibleShape> (*tCreateFunction)
  49     (const AccessibleShapeInfo& rShapeInfo,
  50     const AccessibleShapeTreeInfo& rShapeTreeInfo,
  51     ShapeTypeId nId);
  52
  53 /** Each shape type is described by listing its id, its service name and a
  54     function which creates a new accessible object that can represent that
  55     service.  The id has to be unique with respect to the create function.
  56 */
  57 struct ShapeTypeDescriptor
  58 {
  59     ShapeTypeId         mnShapeTypeId;
  60     OUString       msServiceName;
  61     tCreateFunction     maCreateFunction;
  62     ShapeTypeDescriptor (
  63         ShapeTypeId nId, OUString sName, tCreateFunction aFunction)
  64     :   mnShapeTypeId (nId),
  65         msServiceName (std::move(sName)),
  66            maCreateFunction (aFunction)
  67     {}
  68     ShapeTypeDescriptor()
  69     :   mnShapeTypeId (-1),
  70         maCreateFunction (nullptr)
  71     {}
  72 };
  73
  74 /** @descr
  75         This class is a singleton that has the purpose to transform between
  76         service names of shapes and associated enum values and to create new
  77         accessible objects for given shapes.
  78 */
  79 class SVX_DLLPUBLIC ShapeTypeHandler final
  80 {
  81 public:
  82     enum { UNKNOWN_SHAPE_TYPE = 0 };
  83
  84     /** This function returns a reference to the only instance of this class.
  85         Use this instance to retrieve a shape's type and service name.
  86         @return
  87             Returns a reference to a ShapeTypeHandler object.
  88      */
  89     static ShapeTypeHandler& Instance();
  90
  91     /**  Determines the type id of a shape with the given service name.
  92          @param aServiceName
  93              Service name of the shape for which to return the type id.
  94          @return
  95              Returns the type id of the shape with the given service name or
  96              -1 when the service name is not known.
  97      */
  98     ShapeTypeId GetTypeId (const OUString& aServiceName) const;
  99
 100     /**  Determines the type id of the specified shape.
 101          @param xShape
 102              Reference to the shape for which to return the type id.
 103          @return
 104              Returns the type id of the specified shape or
 105              -1 when the given reference is either not
 106              set or the referenced object does not support the
 107              XShapeDescriptor interface.
 108      */
 109     ShapeTypeId GetTypeId (const css::uno::Reference<
 110         css::drawing::XShape>& rxShape) const;
 111
 112     /**  Create a new accessible object for the given shape.
 113          @param rShapeInfo
 114              Bundle of information passed to the new accessible shape.
 115          @param rShapeTreeInfo
 116              Bundle of information passed down the shape tree.
 117          @return
 118              Pointer to the implementation object that implements the
 119              <code>XAccessible</code> interface.  This pointer may be NULL
 120              if the specified shape is of unknown type.
 121      */
 122     rtl::Reference<AccessibleShape>
 123         CreateAccessibleObject (
 124             const AccessibleShapeInfo& rShapeInfo,
 125             const AccessibleShapeTreeInfo& rShapeTreeInfo) const;
 126
 127     /**  Add new shape types to the internal tables.  Each new shape type is
 128          described by one shape type descriptor.  See
 129          ShapeTypeDescriptor for more details.
 130
 131          @param nDescriptorCount
 132              Number of new shape types.
 133          @param aDescriptorList
 134              Array of new shape type descriptors.
 135      */
 136     void AddShapeTypeList (int nDescriptorCount,
 137         ShapeTypeDescriptor const aDescriptorList[]);
 138
 139     /// get the accessible base name for an object
 140     ///
 141     /// @throws css::uno::RuntimeException
 142     static OUString CreateAccessibleBaseName (
 143         const css::uno::Reference< css::drawing::XShape >& rxShape);
 144
 145 private:
 146     // Declare default constructor, copy constructor, destructor, and
 147     // assignment operation protected so that no one accidentally creates a
 148     // second instance of this singleton class or deletes it.
 149     ShapeTypeHandler();
 150     ShapeTypeHandler (const ShapeTypeHandler& aHandler);             // never implemented, this is a singleton class
 151     ShapeTypeHandler& operator= (const ShapeTypeHandler& aHandler); // never implemented, this is a singleton class
 152
 153     /** This destructor is never called at the moment.  But because this
 154         class is a singleton this is not a problem.
 155     */
 156     ~ShapeTypeHandler();
 157
 158     /// Pointer to the only instance of this class.
 159     static ShapeTypeHandler* instance;
 160
 161     /** List of shape type descriptors.  This list is normally build up in
 162         several steps when libraries that implement shapes are loaded and
 163         call the addShapeTypeList method.  After that no modifications of
 164         the list take place.
 165     */
 166     ::std::vector<ShapeTypeDescriptor> maShapeTypeDescriptorList;
 167
 168     /** This hash map allows the fast look up of a type descriptor for a
 169         given service name.
 170     */
 171     typedef std::unordered_map<OUString,ShapeTypeId> tServiceNameToSlotId;
 172     mutable tServiceNameToSlotId maServiceNameToSlotId;
 173
 174     /**  Determine the slot id of the specified shape type.  With this id
 175          internal methods can access the associated type descriptor.
 176          @param aServiceName
 177              Service name of the shape for which to return the slot id.
 178          @return
 179              Returns the slot id of the shape with the given service name or
 180              0 when the service name is not known.
 181      */
 182     SVX_DLLPRIVATE tools::Long GetSlotId (const OUString& aServiceName) const;
 183
 184     /**  Determine the slot id of the specified shape type.  With this id
 185          internal methods can access the associated type descriptor.
 186          @param rxShape
 187              Shape for which to return the slot id.
 188          @return
 189              Returns the slot id of the shape with the given service name or
 190              0 when the service name is not known.
 191      */
 192     SVX_DLLPRIVATE tools::Long GetSlotId (const css::uno::Reference<
 193         css::drawing::XShape>& rxShape) const;
 194 };
 195
 196 } // end of namespace accessible
 197
 198 #endif
 199
 200 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */