atk/atkgobjectaccessible.c

   1 /* ATK - Accessibility Toolkit
   2  * Copyright 2001, 2002, 2003 Sun Microsystems Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include <atk/atkgobjectaccessible.h>
  21 #include <atk/atkregistry.h>
  22 #include <atk/atkutil.h>
  23
  24 /**
  25  * SECTION:atkgobjectaccessible
  26  * @Short_description: This object class is derived from AtkObject and
  27  *  can be used as a basis implementing accessible objects.
  28  * @Title:AtkGObjectAccessible
  29  *
  30  * This object class is derived from AtkObject. It can be used as a
  31  * basis for implementing accessible objects for GObjects which are
  32  * not derived from GtkWidget. One example of its use is in providing
  33  * an accessible object for GnomeCanvasItem in the GAIL library.
  34  */
  35 static void       atk_gobject_accessible_class_init       (AtkGObjectAccessibleClass   *klass);
  36 static void       atk_real_gobject_accessible_initialize  (AtkObject         *atk_obj,
  37                                                            gpointer          data);
  38 static void       atk_gobject_accessible_dispose          (gpointer          data);
  39
  40 static GQuark quark_accessible_object = 0;
  41 static GQuark quark_object = 0;
  42 static gpointer parent_class = NULL;
  43
  44 GType
  45 atk_gobject_accessible_get_type (void)
  46 {
  47   static GType type = 0;
  48
  49   if (!type)
  50     {
  51       static const GTypeInfo tinfo =
  52       {
  53         sizeof (AtkGObjectAccessibleClass),
  54         (GBaseInitFunc) NULL, /* base init */
  55         (GBaseFinalizeFunc) NULL, /* base finalize */
  56         (GClassInitFunc) atk_gobject_accessible_class_init,
  57         (GClassFinalizeFunc) NULL, /* class finalize */
  58         NULL, /* class data */
  59         sizeof (AtkGObjectAccessible),
  60         0, /* nb preallocs */
  61         (GInstanceInitFunc) NULL, /* instance init */
  62         NULL /* value table */
  63       };
  64
  65       type = g_type_register_static (ATK_TYPE_OBJECT,
  66                                      "AtkGObjectAccessible", &tinfo, 0);
  67     }
  68
  69   return type;
  70 }
  71
  72 /**
  73  * atk_gobject_accessible_for_object:
  74  * @obj: a #GObject
  75  *
  76  * Gets the accessible object for the specified @obj.
  77  *
  78  * Returns: (transfer none): a #AtkObject which is the accessible object for
  79  * the @obj
  80  **/
  81 AtkObject*
  82 atk_gobject_accessible_for_object (GObject *obj)
  83 {
  84   AtkObject* accessible;
  85
  86   g_return_val_if_fail (G_IS_OBJECT (obj), NULL);
  87   /* See if we have a cached accessible for this object */
  88
  89   accessible = g_object_get_qdata (obj,
  90                                    quark_accessible_object);
  91
  92   if (!accessible)
  93     {
  94       AtkObjectFactory *factory;
  95       AtkRegistry *default_registry;
  96
  97       default_registry = atk_get_default_registry ();
  98       factory = atk_registry_get_factory (default_registry,
  99                                           G_OBJECT_TYPE (obj));
 100       accessible = atk_object_factory_create_accessible (factory,
 101                                                          obj);
 102       if (!ATK_IS_GOBJECT_ACCESSIBLE (accessible))
 103         {
 104           /*
 105            * The AtkObject which was created was not a AtkGObjectAccessible
 106            */
 107           g_object_weak_ref (obj,
 108                              (GWeakNotify) g_object_unref,
 109                              accessible);
 110           if (!quark_accessible_object)
 111             quark_accessible_object = g_quark_from_static_string ("accessible-object");
 112         }
 113       g_object_set_qdata (obj, quark_accessible_object, accessible);
 114     }
 115   return accessible;
 116 }
 117
 118 /**
 119  * atk_gobject_accessible_get_object:
 120  * @obj: a #AtkGObjectAccessible
 121  *
 122  * Gets the GObject for which @obj is the accessible object.
 123  *
 124  * Returns: (transfer none): a #GObject which is the object for which @obj is
 125  * the accessible object
 126  **/
 127 GObject *
 128 atk_gobject_accessible_get_object (AtkGObjectAccessible *obj)
 129 {
 130   g_return_val_if_fail (ATK_IS_GOBJECT_ACCESSIBLE (obj), NULL);
 131
 132   return g_object_get_qdata (G_OBJECT (obj), quark_object);
 133 }
 134
 135 static void
 136 atk_real_gobject_accessible_initialize (AtkObject  *atk_obj,
 137                                         gpointer   data)
 138 {
 139   AtkGObjectAccessible *atk_gobj;
 140
 141   atk_gobj = ATK_GOBJECT_ACCESSIBLE (atk_obj);
 142
 143   g_object_set_qdata (G_OBJECT (atk_gobj), quark_object, data);
 144   atk_obj->layer = ATK_LAYER_WIDGET;
 145
 146   g_object_weak_ref (data,
 147                      (GWeakNotify) atk_gobject_accessible_dispose,
 148                      atk_gobj);
 149 }
 150
 151 static void
 152 atk_gobject_accessible_dispose (gpointer  data)
 153 {
 154   GObject *object;
 155
 156   g_return_if_fail (ATK_IS_GOBJECT_ACCESSIBLE (data));
 157
 158   object = atk_gobject_accessible_get_object (data);
 159   if (object)
 160       g_object_set_qdata (object, quark_accessible_object, NULL);
 161
 162   g_object_set_qdata (G_OBJECT (data), quark_object, NULL);
 163   atk_object_notify_state_change (ATK_OBJECT (data), ATK_STATE_DEFUNCT,
 164                                   TRUE);
 165   g_object_unref (data);
 166 }
 167
 168 static void
 169 atk_gobject_accessible_class_init (AtkGObjectAccessibleClass *klass)
 170 {
 171   AtkObjectClass *class;
 172
 173   class = ATK_OBJECT_CLASS (klass);
 174
 175   parent_class = g_type_class_peek_parent (klass);
 176
 177   class->initialize = atk_real_gobject_accessible_initialize;
 178
 179   if (!quark_accessible_object)
 180     quark_accessible_object = g_quark_from_static_string ("accessible-object");
 181   quark_object = g_quark_from_static_string ("object-for-accessible");
 182 }