1 /* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
2 /* eel-accessibility.h - Utility functions for accessibility
3
4 Copyright (C) 2002 Anders Carlsson, Sun Microsystems, Inc.
5
6 The Eel Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
10
11 The Eel Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Library General Public License for more details.
15
16 You should have received a copy of the GNU Library General Public
17 License along with the Eel Library; see the file COPYING.LIB. If not,
18 write to the Free Software Foundation, Inc., 51 Franklin Street - Suite 500,
19 Boston, MA 02110-1335, USA.
20
21 Authors:
22 Anders Carlsson <andersca@gnu.org>
23 Michael Meeks <michael@ximian.com>
24 */
25 #include <config.h>
26 #include <gtk/gtk.h>
27 #include <eel/eel-accessibility.h>
28
29 void
eel_accessibility_set_up_label_widget_relation(GtkWidget * label,GtkWidget * widget)30 eel_accessibility_set_up_label_widget_relation (GtkWidget *label, GtkWidget *widget)
31 {
32 AtkObject *atk_widget, *atk_label;
33
34 atk_label = gtk_widget_get_accessible (label);
35 atk_widget = gtk_widget_get_accessible (widget);
36
37 /* Create the label -> widget relation */
38 atk_object_add_relationship (atk_label, ATK_RELATION_LABEL_FOR, atk_widget);
39
40 /* Create the widget -> label relation */
41 atk_object_add_relationship (atk_widget, ATK_RELATION_LABELLED_BY, atk_label);
42 }
43
44 /*
45 * Hacks to make re-using gail somewhat easier.
46 */
47
48 /**
49 * eel_accessibility_create_derived_type:
50 * @type_name: the name for the new accessible type eg. NemoIconCanvasItemAccessible
51 * @existing_gobject_with_proxy: the GType of an object that has a registered factory that
52 * manufactures the type we want to inherit from. ie. to inherit from a GailCanvasItem
53 * we need to pass GNOME_TYPE_CANVAS_ITEM - since GailCanvasItem is registered against
54 * that type.
55 * @opt_gail_parent_class: the name of the Gail class to derive from eg. GailCanvasItem
56 * @class_init: the init function to run for this class
57 *
58 * This should be run to register the type, it can subsequently be run with
59 * the same name and will not re-register it, but simply return it.
60 *
61 * NB. to do instance init, you prolly want to override AtkObject::initialize
62 *
63 * Return value: the registered type, or 0 on failure.
64 **/
65 GType
eel_accessibility_create_derived_type(const char * type_name,GType existing_gobject_with_proxy,EelAccessibilityClassInitFn class_init)66 eel_accessibility_create_derived_type (const char *type_name,
67 GType existing_gobject_with_proxy,
68 EelAccessibilityClassInitFn class_init)
69 {
70 GType type;
71 GType parent_atk_type;
72 GTypeInfo tinfo = { 0 };
73 GTypeQuery query;
74 AtkObjectFactory *factory;
75
76 if ((type = g_type_from_name (type_name))) {
77 return type;
78 }
79
80 factory = atk_registry_get_factory
81 (atk_get_default_registry (),
82 existing_gobject_with_proxy);
83 if (!factory) {
84 return G_TYPE_INVALID;
85 }
86
87 parent_atk_type = atk_object_factory_get_accessible_type (factory);
88 if (!parent_atk_type) {
89 return G_TYPE_INVALID;
90 }
91
92 /*
93 * Figure out the size of the class and instance
94 * we are deriving from
95 */
96 g_type_query (parent_atk_type, &query);
97
98 if (class_init) {
99 tinfo.class_init = (GClassInitFunc) class_init;
100 }
101
102 tinfo.class_size = query.class_size;
103 tinfo.instance_size = query.instance_size;
104
105 /* Register the type */
106 type = g_type_register_static (
107 parent_atk_type, type_name, &tinfo, 0);
108
109 return type;
110 }
111
112
113 static GQuark
get_quark_accessible(void)114 get_quark_accessible (void)
115 {
116 static GQuark quark_accessible_object = 0;
117
118 if (!quark_accessible_object) {
119 quark_accessible_object = g_quark_from_static_string
120 ("accessible-object");
121 }
122
123 return quark_accessible_object;
124 }
125
126 static GQuark
get_quark_gobject(void)127 get_quark_gobject (void)
128 {
129 static GQuark quark_accessible_gobject = 0;
130
131 if (!quark_accessible_gobject) {
132 quark_accessible_gobject = g_quark_from_static_string
133 ("object-for-accessible");
134 }
135
136 return quark_accessible_gobject;
137 }
138
139 /**
140 * eel_accessibility_get_atk_object:
141 * @object: a GObject of some sort
142 *
143 * gets an AtkObject associated with a GObject
144 *
145 * Return value: the associated accessible if one exists or NULL
146 **/
147 AtkObject *
eel_accessibility_get_atk_object(gpointer object)148 eel_accessibility_get_atk_object (gpointer object)
149 {
150 return g_object_get_qdata (object, get_quark_accessible ());
151 }
152
153 /**
154 * eel_accessibilty_for_object:
155 * @object: a GObject of some sort
156 *
157 * gets an AtkObject associated with a GObject and if it doesn't
158 * exist creates a suitable accessible object.
159 *
160 * Return value: an associated accessible.
161 **/
162 AtkObject *
eel_accessibility_for_object(gpointer object)163 eel_accessibility_for_object (gpointer object)
164 {
165 if (GTK_IS_WIDGET (object))
166 return gtk_widget_get_accessible (object);
167
168 return atk_gobject_accessible_for_object (object);
169 }
170
171 /**
172 * eel_accessibility_get_gobject:
173 * @object: an AtkObject
174 *
175 * gets the GObject associated with the AtkObject, for which
176 * @object provides accessibility support.
177 *
178 * Return value: the accessible's associated GObject
179 **/
180 gpointer
eel_accessibility_get_gobject(AtkObject * object)181 eel_accessibility_get_gobject (AtkObject *object)
182 {
183 return g_object_get_qdata (G_OBJECT (object), get_quark_gobject ());
184 }
185
186 static void
eel_accessibility_destroy(gpointer data)187 eel_accessibility_destroy (gpointer data)
188 {
189 g_object_set_qdata (G_OBJECT (data), get_quark_gobject (), NULL);
190 atk_object_notify_state_change (ATK_OBJECT (data), ATK_STATE_DEFUNCT, TRUE);
191 g_object_unref (data);
192 }
193
194 /**
195 * eel_accessibility_set_atk_object_return:
196 * @object: a GObject
197 * @atk_object: it's AtkObject
198 *
199 * used to register and return a new accessible object for something
200 *
201 * Return value: @atk_object.
202 **/
203 AtkObject *
eel_accessibility_set_atk_object_return(gpointer object,AtkObject * atk_object)204 eel_accessibility_set_atk_object_return (gpointer object,
205 AtkObject *atk_object)
206 {
207 atk_object_initialize (atk_object, object);
208
209 if (!ATK_IS_GOBJECT_ACCESSIBLE (atk_object)) {
210 g_object_set_qdata_full
211 (object, get_quark_accessible (), atk_object, eel_accessibility_destroy);
212 g_object_set_qdata
213 (G_OBJECT (atk_object), get_quark_gobject (), object);
214 }
215
216 return atk_object;
217 }
218
219 static GailTextUtil *
get_simple_text(gpointer object)220 get_simple_text (gpointer object)
221 {
222 GObject *gobject;
223 EelAccessibleTextIface *aif;
224
225 if (GTK_IS_ACCESSIBLE (object)) {
226 gobject = G_OBJECT (gtk_accessible_get_widget (GTK_ACCESSIBLE (object)));
227 } else {
228 gobject = eel_accessibility_get_gobject (object);
229 }
230
231 if (!gobject) {
232 return NULL;
233 }
234
235 aif = EEL_ACCESSIBLE_TEXT_GET_IFACE (gobject);
236 if (!aif) {
237 g_warning ("No accessible text inferface on '%s'",
238 g_type_name_from_instance ((gpointer) gobject));
239
240 } else if (aif->get_text) {
241 return aif->get_text (gobject);
242 }
243
244 return NULL;
245 }
246
247 char *
eel_accessibility_text_get_text(AtkText * text,gint start_pos,gint end_pos)248 eel_accessibility_text_get_text (AtkText *text,
249 gint start_pos,
250 gint end_pos)
251 {
252 GailTextUtil *util = get_simple_text (text);
253 g_return_val_if_fail (util != NULL, NULL);
254
255 return gail_text_util_get_substring (util, start_pos, end_pos);
256 }
257
258 gunichar
eel_accessibility_text_get_character_at_offset(AtkText * text,gint offset)259 eel_accessibility_text_get_character_at_offset (AtkText *text,
260 gint offset)
261 {
262 char *txt, *index;
263 gint sucks1 = 0, sucks2 = -1;
264 gunichar c;
265 GailTextUtil *util = get_simple_text (text);
266 g_return_val_if_fail (util != NULL, 0);
267
268 txt = gail_text_util_get_substring (util, sucks1, sucks2);
269
270 index = g_utf8_offset_to_pointer (txt, offset);
271 c = g_utf8_get_char (index);
272 g_free (txt);
273
274 return c;
275 }
276
277 char *
eel_accessibility_text_get_text_before_offset(AtkText * text,gint offset,AtkTextBoundary boundary_type,gint * start_offset,gint * end_offset)278 eel_accessibility_text_get_text_before_offset (AtkText *text,
279 gint offset,
280 AtkTextBoundary boundary_type,
281 gint *start_offset,
282 gint *end_offset)
283 {
284 GailTextUtil *util = get_simple_text (text);
285 g_return_val_if_fail (util != NULL, NULL);
286
287 return gail_text_util_get_text (
288 util, NULL, GAIL_BEFORE_OFFSET,
289 boundary_type, offset, start_offset, end_offset);
290 }
291
292 char *
eel_accessibility_text_get_text_at_offset(AtkText * text,gint offset,AtkTextBoundary boundary_type,gint * start_offset,gint * end_offset)293 eel_accessibility_text_get_text_at_offset (AtkText *text,
294 gint offset,
295 AtkTextBoundary boundary_type,
296 gint *start_offset,
297 gint *end_offset)
298 {
299 GailTextUtil *util = get_simple_text (text);
300 g_return_val_if_fail (util != NULL, NULL);
301
302 return gail_text_util_get_text (
303 util, NULL, GAIL_AT_OFFSET,
304 boundary_type, offset, start_offset, end_offset);
305 }
306
307 gchar*
eel_accessibility_text_get_text_after_offset(AtkText * text,gint offset,AtkTextBoundary boundary_type,gint * start_offset,gint * end_offset)308 eel_accessibility_text_get_text_after_offset (AtkText *text,
309 gint offset,
310 AtkTextBoundary boundary_type,
311 gint *start_offset,
312 gint *end_offset)
313 {
314 GailTextUtil *util = get_simple_text (text);
315 g_return_val_if_fail (util != NULL, NULL);
316
317 return gail_text_util_get_text (
318 util, NULL, GAIL_AFTER_OFFSET,
319 boundary_type, offset, start_offset, end_offset);
320 }
321
322 gint
eel_accessibility_text_get_character_count(AtkText * text)323 eel_accessibility_text_get_character_count (AtkText *text)
324 {
325 GailTextUtil *util = get_simple_text (text);
326 g_return_val_if_fail (util != NULL, -1);
327
328 return gtk_text_buffer_get_char_count (util->buffer);
329 }
330
331 GType
eel_accessible_text_get_type(void)332 eel_accessible_text_get_type (void)
333 {
334 static GType type = 0;
335
336 if (!type) {
337 const GTypeInfo tinfo = {
338 sizeof (AtkTextIface),
339 (GBaseInitFunc) NULL,
340 (GBaseFinalizeFunc) NULL,
341 (GClassInitFunc) NULL,
342 (GClassFinalizeFunc) NULL
343 };
344
345 type = g_type_register_static (
346 G_TYPE_INTERFACE, "EelAccessibleText", &tinfo, 0);
347 }
348
349 return type;
350 }
351