src/libgnomecanvas/gailcanvas.c

   1 /* GAIL - The GNOME Accessibility Implementation Library
   2  * Copyright 2001, 2002, 2003 Sun Microsystems Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  10  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  15  */
  16
  17 #include "evolution-config.h"
  18
  19 #include <gtk/gtk.h>
  20 #include <libgnomecanvas/gnome-canvas.h>
  21 #include <libgnomecanvas/gnome-canvas-text.h>
  22 #include <libgnomecanvas/gnome-canvas-widget.h>
  23 #include "gailcanvas.h"
  24 #include "gailcanvasitem.h"
  25 #include "gailcanvasgroupfactory.h"
  26 #include "gailcanvastextfactory.h"
  27 #include "gailcanvasitemfactory.h"
  28 #include "gailcanvaswidgetfactory.h"
  29
  30 static void       gail_canvas_real_initialize     (AtkObject       *obj,
  31                                                    gpointer        data);
  32
  33 static gint       gail_canvas_get_n_children      (AtkObject       *obj);
  34 static AtkObject * gail_canvas_ref_child           (AtkObject       *obj,
  35                                                    gint            i);
  36
  37 static void       adjustment_changed              (GtkAdjustment   *adjustment,
  38                                                    GnomeCanvas     *canvas);
  39
  40 G_DEFINE_TYPE (GailCanvas, gail_canvas, GTK_TYPE_CONTAINER_ACCESSIBLE)
  41
  42 static void
  43 gail_canvas_init (GailCanvas *canvas)
  44 {
  45 }
  46
  47 /**
  48  * Tell ATK how to create the appropriate AtkObject peers
  49  **/
  50 void
  51 gail_canvas_a11y_init (void)
  52 {
  53   atk_registry_set_factory_type (atk_get_default_registry (),
  54                                  GNOME_TYPE_CANVAS_GROUP,
  55                                  gail_canvas_group_factory_get_type ());
  56   atk_registry_set_factory_type (atk_get_default_registry (),
  57                                  GNOME_TYPE_CANVAS_TEXT,
  58                                  gail_canvas_text_factory_get_type ());
  59   atk_registry_set_factory_type (atk_get_default_registry (),
  60                                  GNOME_TYPE_CANVAS_WIDGET,
  61                                  gail_canvas_widget_factory_get_type ());
  62   atk_registry_set_factory_type (atk_get_default_registry (),
  63                                  GNOME_TYPE_CANVAS_ITEM,
  64                                  gail_canvas_item_factory_get_type ());
  65 }
  66
  67 static void
  68 gail_canvas_class_init (GailCanvasClass *klass)
  69 {
  70   AtkObjectClass *class = ATK_OBJECT_CLASS (klass);
  71
  72   class->get_n_children = gail_canvas_get_n_children;
  73   class->ref_child = gail_canvas_ref_child;
  74   class->initialize = gail_canvas_real_initialize;
  75 }
  76
  77 AtkObject *
  78 gail_canvas_new (GtkWidget *widget)
  79 {
  80   GObject *object;
  81   AtkObject *accessible;
  82
  83   g_return_val_if_fail (GNOME_IS_CANVAS (widget), NULL);
  84
  85   object = g_object_new (GAIL_TYPE_CANVAS, NULL);
  86
  87   accessible = ATK_OBJECT (object);
  88   atk_object_initialize (accessible, widget);
  89
  90   return accessible;
  91 }
  92
  93 static void
  94 gail_canvas_real_initialize (AtkObject *obj,
  95                              gpointer data)
  96 {
  97         GnomeCanvas *canvas;
  98         GtkAdjustment *adj;
  99
 100         ATK_OBJECT_CLASS (gail_canvas_parent_class)->initialize (obj, data);
 101
 102         canvas = GNOME_CANVAS (data);
 103
 104         adj = gtk_scrollable_get_hadjustment (GTK_SCROLLABLE (canvas));
 105         g_signal_connect (
 106                 adj, "value_changed",
 107                 G_CALLBACK (adjustment_changed), canvas);
 108
 109         adj = gtk_scrollable_get_vadjustment (GTK_SCROLLABLE (canvas));
 110         g_signal_connect (
 111                 adj, "value_changed",
 112                 G_CALLBACK (adjustment_changed), canvas);
 113
 114         obj->role = ATK_ROLE_LAYERED_PANE;
 115 }
 116
 117 static gint
 118 gail_canvas_get_n_children (AtkObject *obj)
 119 {
 120   GtkAccessible *accessible;
 121   GtkWidget *widget;
 122   GnomeCanvas *canvas;
 123   GnomeCanvasGroup *root_group;
 124
 125   g_return_val_if_fail (GAIL_IS_CANVAS (obj), 0);
 126
 127   accessible = GTK_ACCESSIBLE (obj);
 128   widget = gtk_accessible_get_widget (accessible);
 129   if (widget == NULL)
 130     /* State is defunct */
 131     return 0;
 132
 133   g_return_val_if_fail (GNOME_IS_CANVAS (widget), 0);
 134
 135   canvas = GNOME_CANVAS (widget);
 136   root_group = gnome_canvas_root (canvas);
 137   g_return_val_if_fail (root_group, 0);
 138   return 1;
 139 }
 140
 141 static AtkObject *
 142 gail_canvas_ref_child (AtkObject *obj,
 143                        gint i)
 144 {
 145   GtkAccessible *accessible;
 146   GtkWidget *widget;
 147   GnomeCanvas *canvas;
 148   GnomeCanvasGroup *root_group;
 149   AtkObject *atk_object;
 150
 151   /* Canvas only has one child, so return NULL if anything else is requested */
 152   if (i != 0)
 153     return NULL;
 154   g_return_val_if_fail (GAIL_IS_CANVAS (obj), NULL);
 155
 156   accessible = GTK_ACCESSIBLE (obj);
 157   widget = gtk_accessible_get_widget (accessible);
 158   if (widget == NULL)
 159     /* State is defunct */
 160     return NULL;
 161   g_return_val_if_fail (GNOME_IS_CANVAS (widget), NULL);
 162
 163   canvas = GNOME_CANVAS (widget);
 164   root_group = gnome_canvas_root (canvas);
 165   g_return_val_if_fail (root_group, NULL);
 166
 167   atk_object = atk_gobject_accessible_for_object (G_OBJECT (root_group));
 168   g_object_ref (atk_object);
 169   return atk_object;
 170 }
 171
 172 static void
 173 adjustment_changed (GtkAdjustment *adjustment,
 174                     GnomeCanvas *canvas)
 175 {
 176   AtkObject *atk_obj;
 177
 178   /*
 179    * The scrollbars have changed
 180    */
 181   atk_obj = gtk_widget_get_accessible (GTK_WIDGET (canvas));
 182
 183   g_signal_emit_by_name (atk_obj, "visible_data_changed");
 184 }
 185