gio/gmenumodel.c

   1 /*
   2  * Copyright © 2011 Canonical Ltd.
   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 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful, but
  10  * 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, see <http://www.gnu.org/licenses/>.
  16  *
  17  * Author: Ryan Lortie <desrt@desrt.ca>
  18  */
  19
  20 #include "config.h"
  21
  22 #include "gmenumodel.h"
  23
  24 #include "glibintl.h"
  25
  26 /**
  27  * SECTION:gmenumodel
  28  * @title: GMenuModel
  29  * @short_description: An abstract class representing the contents of a menu
  30  * @include: gio/gio.h
  31  * @see_also: #GActionGroup
  32  *
  33  * #GMenuModel represents the contents of a menu -- an ordered list of
  34  * menu items. The items are associated with actions, which can be
  35  * activated through them. Items can be grouped in sections, and may
  36  * have submenus associated with them. Both items and sections usually
  37  * have some representation data, such as labels or icons. The type of
  38  * the associated action (ie whether it is stateful, and what kind of
  39  * state it has) can influence the representation of the item.
  40  *
  41  * The conceptual model of menus in #GMenuModel is hierarchical:
  42  * sections and submenus are again represented by #GMenuModels.
  43  * Menus themselves do not define their own roles. Rather, the role
  44  * of a particular #GMenuModel is defined by the item that references
  45  * it (or, in the case of the 'root' menu, is defined by the context
  46  * in which it is used).
  47  *
  48  * As an example, consider the visible portions of this menu:
  49  *
  50  * ## An example menu # {#menu-example}
  51  *
  52  * ![](menu-example.png)
  53  *
  54  * There are 8 "menus" visible in the screenshot: one menubar, two
  55  * submenus and 5 sections:
  56  *
  57  * - the toplevel menubar (containing 4 items)
  58  * - the View submenu (containing 3 sections)
  59  * - the first section of the View submenu (containing 2 items)
  60  * - the second section of the View submenu (containing 1 item)
  61  * - the final section of the View submenu (containing 1 item)
  62  * - the Highlight Mode submenu (containing 2 sections)
  63  * - the Sources section (containing 2 items)
  64  * - the Markup section (containing 2 items)
  65  *
  66  * The [example][menu-model] illustrates the conceptual connection between
  67  * these 8 menus. Each large block in the figure represents a menu and the
  68  * smaller blocks within the large block represent items in that menu. Some
  69  * items contain references to other menus.
  70  *
  71  * ## A menu example # {#menu-model}
  72  *
  73  * ![](menu-model.png)
  74  *
  75  * Notice that the separators visible in the [example][menu-example]
  76  * appear nowhere in the [menu model][menu-model]. This is because
  77  * separators are not explicitly represented in the menu model. Instead,
  78  * a separator is inserted between any two non-empty sections of a menu.
  79  * Section items can have labels just like any other item. In that case,
  80  * a display system may show a section header instead of a separator.
  81  *
  82  * The motivation for this abstract model of application controls is
  83  * that modern user interfaces tend to make these controls available
  84  * outside the application. Examples include global menus, jumplists,
  85  * dash boards, etc. To support such uses, it is necessary to 'export'
  86  * information about actions and their representation in menus, which
  87  * is exactly what the [GActionGroup exporter][gio-GActionGroup-exporter]
  88  * and the [GMenuModel exporter][gio-GMenuModel-exporter] do for
  89  * #GActionGroup and #GMenuModel. The client-side counterparts to
  90  * make use of the exported information are #GDBusActionGroup and
  91  * #GDBusMenuModel.
  92  *
  93  * The API of #GMenuModel is very generic, with iterators for the
  94  * attributes and links of an item, see g_menu_model_iterate_item_attributes()
  95  * and g_menu_model_iterate_item_links(). The 'standard' attributes and
  96  * link types have predefined names: %G_MENU_ATTRIBUTE_LABEL,
  97  * %G_MENU_ATTRIBUTE_ACTION, %G_MENU_ATTRIBUTE_TARGET, %G_MENU_LINK_SECTION
  98  * and %G_MENU_LINK_SUBMENU.
  99  *
 100  * Items in a #GMenuModel represent active controls if they refer to
 101  * an action that can get activated when the user interacts with the
 102  * menu item. The reference to the action is encoded by the string id
 103  * in the %G_MENU_ATTRIBUTE_ACTION attribute. An action id uniquely
 104  * identifies an action in an action group. Which action group(s) provide
 105  * actions depends on the context in which the menu model is used.
 106  * E.g. when the model is exported as the application menu of a
 107  * #GtkApplication, actions can be application-wide or window-specific
 108  * (and thus come from two different action groups). By convention, the
 109  * application-wide actions have names that start with "app.", while the
 110  * names of window-specific actions start with "win.".
 111  *
 112  * While a wide variety of stateful actions is possible, the following
 113  * is the minimum that is expected to be supported by all users of exported
 114  * menu information:
 115  * - an action with no parameter type and no state
 116  * - an action with no parameter type and boolean state
 117  * - an action with string parameter type and string state
 118  *
 119  * ## Stateless
 120  *
 121  * A stateless action typically corresponds to an ordinary menu item.
 122  *
 123  * Selecting such a menu item will activate the action (with no parameter).
 124  *
 125  * ## Boolean State
 126  *
 127  * An action with a boolean state will most typically be used with a "toggle"
 128  * or "switch" menu item. The state can be set directly, but activating the
 129  * action (with no parameter) results in the state being toggled.
 130  *
 131  * Selecting a toggle menu item will activate the action. The menu item should
 132  * be rendered as "checked" when the state is true.
 133  *
 134  * ## String Parameter and State
 135  *
 136  * Actions with string parameters and state will most typically be used to
 137  * represent an enumerated choice over the items available for a group of
 138  * radio menu items. Activating the action with a string parameter is
 139  * equivalent to setting that parameter as the state.
 140  *
 141  * Radio menu items, in addition to being associated with the action, will
 142  * have a target value. Selecting that menu item will result in activation
 143  * of the action with the target value as the parameter. The menu item should
 144  * be rendered as "selected" when the state of the action is equal to the
 145  * target value of the menu item.
 146  */
 147
 148 /**
 149  * GMenuModel:
 150  *
 151  * #GMenuModel is an opaque structure type.  You must access it using the
 152  * functions below.
 153  *
 154  * Since: 2.32
 155  */
 156
 157 /**
 158  * GMenuAttributeIter:
 159  *
 160  * #GMenuAttributeIter is an opaque structure type.  You must access it
 161  * using the functions below.
 162  *
 163  * Since: 2.32
 164  */
 165
 166 /**
 167  * GMenuLinkIter:
 168  *
 169  * #GMenuLinkIter is an opaque structure type.  You must access it using
 170  * the functions below.
 171  *
 172  * Since: 2.32
 173  */
 174
 175 typedef struct
 176 {
 177   GMenuLinkIter parent_instance;
 178   GHashTableIter iter;
 179   GHashTable *table;
 180 } GMenuLinkHashIter;
 181
 182 typedef GMenuLinkIterClass GMenuLinkHashIterClass;
 183
 184 static GType g_menu_link_hash_iter_get_type (void);
 185
 186 G_DEFINE_TYPE (GMenuLinkHashIter, g_menu_link_hash_iter, G_TYPE_MENU_LINK_ITER)
 187
 188 static gboolean
 189 g_menu_link_hash_iter_get_next (GMenuLinkIter  *link_iter,
 190                                 const gchar   **out_name,
 191                                 GMenuModel    **value)
 192 {
 193   GMenuLinkHashIter *iter = (GMenuLinkHashIter *) link_iter;
 194   gpointer keyptr, valueptr;
 195
 196   if (!g_hash_table_iter_next (&iter->iter, &keyptr, &valueptr))
 197     return FALSE;
 198
 199   *out_name = keyptr;
 200   *value = g_object_ref (valueptr);
 201
 202   return TRUE;
 203 }
 204
 205 static void
 206 g_menu_link_hash_iter_finalize (GObject *object)
 207 {
 208   GMenuLinkHashIter *iter = (GMenuLinkHashIter *) object;
 209
 210   g_hash_table_unref (iter->table);
 211
 212   G_OBJECT_CLASS (g_menu_link_hash_iter_parent_class)
 213     ->finalize (object);
 214 }
 215
 216 static void
 217 g_menu_link_hash_iter_init (GMenuLinkHashIter *iter)
 218 {
 219 }
 220
 221 static void
 222 g_menu_link_hash_iter_class_init (GMenuLinkHashIterClass *class)
 223 {
 224   GObjectClass *object_class = G_OBJECT_CLASS (class);
 225
 226   object_class->finalize = g_menu_link_hash_iter_finalize;
 227   class->get_next = g_menu_link_hash_iter_get_next;
 228 }
 229
 230
 231 typedef struct
 232 {
 233   GMenuAttributeIter parent_instance;
 234   GHashTableIter iter;
 235   GHashTable *table;
 236 } GMenuAttributeHashIter;
 237
 238 typedef GMenuAttributeIterClass GMenuAttributeHashIterClass;
 239
 240 static GType g_menu_attribute_hash_iter_get_type (void);
 241
 242 G_DEFINE_TYPE (GMenuAttributeHashIter, g_menu_attribute_hash_iter, G_TYPE_MENU_ATTRIBUTE_ITER)
 243
 244 static gboolean
 245 g_menu_attribute_hash_iter_get_next (GMenuAttributeIter  *attr_iter,
 246                                      const gchar        **name,
 247                                      GVariant           **value)
 248 {
 249   GMenuAttributeHashIter *iter = (GMenuAttributeHashIter *) attr_iter;
 250   gpointer keyptr, valueptr;
 251
 252   if (!g_hash_table_iter_next (&iter->iter, &keyptr, &valueptr))
 253     return FALSE;
 254
 255   *name = keyptr;
 256
 257   *value = g_variant_ref (valueptr);
 258
 259   return TRUE;
 260 }
 261
 262 static void
 263 g_menu_attribute_hash_iter_finalize (GObject *object)
 264 {
 265   GMenuAttributeHashIter *iter = (GMenuAttributeHashIter *) object;
 266
 267   g_hash_table_unref (iter->table);
 268
 269   G_OBJECT_CLASS (g_menu_attribute_hash_iter_parent_class)
 270     ->finalize (object);
 271 }
 272
 273 static void
 274 g_menu_attribute_hash_iter_init (GMenuAttributeHashIter *iter)
 275 {
 276 }
 277
 278 static void
 279 g_menu_attribute_hash_iter_class_init (GMenuAttributeHashIterClass *class)
 280 {
 281   GObjectClass *object_class = G_OBJECT_CLASS (class);
 282
 283   object_class->finalize = g_menu_attribute_hash_iter_finalize;
 284   class->get_next = g_menu_attribute_hash_iter_get_next;
 285 }
 286
 287 G_DEFINE_ABSTRACT_TYPE (GMenuModel, g_menu_model, G_TYPE_OBJECT)
 288
 289
 290 static guint g_menu_model_items_changed_signal;
 291
 292 static GMenuAttributeIter *
 293 g_menu_model_real_iterate_item_attributes (GMenuModel *model,
 294                                            gint        item_index)
 295 {
 296   GHashTable *table = NULL;
 297   GMenuAttributeIter *result;
 298
 299   G_MENU_MODEL_GET_CLASS (model)->get_item_attributes (model, item_index, &table);
 300
 301   if (table)
 302     {
 303       GMenuAttributeHashIter *iter = g_object_new (g_menu_attribute_hash_iter_get_type (), NULL);
 304       g_hash_table_iter_init (&iter->iter, table);
 305       iter->table = g_hash_table_ref (table);
 306       result = G_MENU_ATTRIBUTE_ITER (iter);
 307     }
 308   else
 309     {
 310       g_critical ("GMenuModel implementation '%s' doesn't override iterate_item_attributes() "
 311                   "and fails to return sane values from get_item_attributes()",
 312                   G_OBJECT_TYPE_NAME (model));
 313       result = NULL;
 314     }
 315
 316   if (table != NULL)
 317     g_hash_table_unref (table);
 318
 319   return result;
 320 }
 321
 322 static GVariant *
 323 g_menu_model_real_get_item_attribute_value (GMenuModel         *model,
 324                                             gint                item_index,
 325                                             const gchar        *attribute,
 326                                             const GVariantType *expected_type)
 327 {
 328   GHashTable *table = NULL;
 329   GVariant *value = NULL;
 330
 331   G_MENU_MODEL_GET_CLASS (model)
 332     ->get_item_attributes (model, item_index, &table);
 333
 334   if (table != NULL)
 335     {
 336       value = g_hash_table_lookup (table, attribute);
 337
 338       if (value != NULL)
 339         {
 340           if (expected_type == NULL || g_variant_is_of_type (value, expected_type))
 341             value = g_variant_ref (value);
 342           else
 343             value = NULL;
 344         }
 345     }
 346   else
 347     g_assert_not_reached ();
 348
 349   if (table != NULL)
 350     g_hash_table_unref (table);
 351
 352   return value;
 353 }
 354
 355 static GMenuLinkIter *
 356 g_menu_model_real_iterate_item_links (GMenuModel *model,
 357                                       gint        item_index)
 358 {
 359   GHashTable *table = NULL;
 360   GMenuLinkIter *result;
 361
 362   G_MENU_MODEL_GET_CLASS (model)
 363     ->get_item_links (model, item_index, &table);
 364
 365   if (table)
 366     {
 367       GMenuLinkHashIter *iter = g_object_new (g_menu_link_hash_iter_get_type (), NULL);
 368       g_hash_table_iter_init (&iter->iter, table);
 369       iter->table = g_hash_table_ref (table);
 370       result = G_MENU_LINK_ITER (iter);
 371     }
 372   else
 373     {
 374       g_critical ("GMenuModel implementation '%s' doesn't override iterate_item_links() "
 375                   "and fails to return sane values from get_item_links()",
 376                   G_OBJECT_TYPE_NAME (model));
 377       result = NULL;
 378     }
 379
 380   if (table != NULL)
 381     g_hash_table_unref (table);
 382
 383   return result;
 384 }
 385
 386 static GMenuModel *
 387 g_menu_model_real_get_item_link (GMenuModel  *model,
 388                                  gint         item_index,
 389                                  const gchar *link)
 390 {
 391   GHashTable *table = NULL;
 392   GMenuModel *value = NULL;
 393
 394   G_MENU_MODEL_GET_CLASS (model)
 395     ->get_item_links (model, item_index, &table);
 396
 397   if (table != NULL)
 398     value = g_hash_table_lookup (table, link);
 399   else
 400     g_assert_not_reached ();
 401
 402   if (value != NULL)
 403     g_object_ref (value);
 404
 405   if (table != NULL)
 406     g_hash_table_unref (table);
 407
 408   return value;
 409 }
 410
 411 static void
 412 g_menu_model_init (GMenuModel *model)
 413 {
 414 }
 415
 416 static void
 417 g_menu_model_class_init (GMenuModelClass *class)
 418 {
 419   class->iterate_item_attributes = g_menu_model_real_iterate_item_attributes;
 420   class->get_item_attribute_value = g_menu_model_real_get_item_attribute_value;
 421   class->iterate_item_links = g_menu_model_real_iterate_item_links;
 422   class->get_item_link = g_menu_model_real_get_item_link;
 423
 424   /**
 425    * GMenuModel::items-changed:
 426    * @model: the #GMenuModel that is changing
 427    * @position: the position of the change
 428    * @removed: the number of items removed
 429    * @added: the number of items added
 430    *
 431    * Emitted when a change has occured to the menu.
 432    *
 433    * The only changes that can occur to a menu is that items are removed
 434    * or added.  Items may not change (except by being removed and added
 435    * back in the same location).  This signal is capable of describing
 436    * both of those changes (at the same time).
 437    *
 438    * The signal means that starting at the index @position, @removed
 439    * items were removed and @added items were added in their place.  If
 440    * @removed is zero then only items were added.  If @added is zero
 441    * then only items were removed.
 442    *
 443    * As an example, if the menu contains items a, b, c, d (in that
 444    * order) and the signal (2, 1, 3) occurs then the new composition of
 445    * the menu will be a, b, _, _, _, d (with each _ representing some
 446    * new item).
 447    *
 448    * Signal handlers may query the model (particularly the added items)
 449    * and expect to see the results of the modification that is being
 450    * reported.  The signal is emitted after the modification.
 451    **/
 452   g_menu_model_items_changed_signal =
 453     g_signal_new (I_("items-changed"), G_TYPE_MENU_MODEL,
 454                   G_SIGNAL_RUN_LAST, 0, NULL, NULL,
 455                   g_cclosure_marshal_generic, G_TYPE_NONE,
 456                   3, G_TYPE_INT, G_TYPE_INT, G_TYPE_INT);
 457 }
 458
 459 /**
 460  * g_menu_model_is_mutable:
 461  * @model: a #GMenuModel
 462  *
 463  * Queries if @model is mutable.
 464  *
 465  * An immutable #GMenuModel will never emit the #GMenuModel::items-changed
 466  * signal. Consumers of the model may make optimisations accordingly.
 467  *
 468  * Returns: %TRUE if the model is mutable (ie: "items-changed" may be
 469  *     emitted).
 470  *
 471  * Since: 2.32
 472  */
 473 gboolean
 474 g_menu_model_is_mutable (GMenuModel *model)
 475 {
 476   return G_MENU_MODEL_GET_CLASS (model)
 477     ->is_mutable (model);
 478 }
 479
 480 /**
 481  * g_menu_model_get_n_items:
 482  * @model: a #GMenuModel
 483  *
 484  * Query the number of items in @model.
 485  *
 486  * Returns: the number of items
 487  *
 488  * Since: 2.32
 489  */
 490 gint
 491 g_menu_model_get_n_items (GMenuModel *model)
 492 {
 493   return G_MENU_MODEL_GET_CLASS (model)
 494     ->get_n_items (model);
 495 }
 496
 497 /**
 498  * g_menu_model_iterate_item_attributes:
 499  * @model: a #GMenuModel
 500  * @item_index: the index of the item
 501  *
 502  * Creates a #GMenuAttributeIter to iterate over the attributes of
 503  * the item at position @item_index in @model.
 504  *
 505  * You must free the iterator with g_object_unref() when you are done.
 506  *
 507  * Returns: (transfer full): a new #GMenuAttributeIter
 508  *
 509  * Since: 2.32
 510  */
 511 GMenuAttributeIter *
 512 g_menu_model_iterate_item_attributes (GMenuModel *model,
 513                                       gint        item_index)
 514 {
 515   return G_MENU_MODEL_GET_CLASS (model)
 516     ->iterate_item_attributes (model, item_index);
 517 }
 518
 519 /**
 520  * g_menu_model_get_item_attribute_value:
 521  * @model: a #GMenuModel
 522  * @item_index: the index of the item
 523  * @attribute: the attribute to query
 524  * @expected_type: (nullable): the expected type of the attribute, or
 525  *     %NULL
 526  *
 527  * Queries the item at position @item_index in @model for the attribute
 528  * specified by @attribute.
 529  *
 530  * If @expected_type is non-%NULL then it specifies the expected type of
 531  * the attribute.  If it is %NULL then any type will be accepted.
 532  *
 533  * If the attribute exists and matches @expected_type (or if the
 534  * expected type is unspecified) then the value is returned.
 535  *
 536  * If the attribute does not exist, or does not match the expected type
 537  * then %NULL is returned.
 538  *
 539  * Returns: (transfer full): the value of the attribute
 540  *
 541  * Since: 2.32
 542  */
 543 GVariant *
 544 g_menu_model_get_item_attribute_value (GMenuModel         *model,
 545                                        gint                item_index,
 546                                        const gchar        *attribute,
 547                                        const GVariantType *expected_type)
 548 {
 549   return G_MENU_MODEL_GET_CLASS (model)
 550     ->get_item_attribute_value (model, item_index, attribute, expected_type);
 551 }
 552
 553 /**
 554  * g_menu_model_get_item_attribute:
 555  * @model: a #GMenuModel
 556  * @item_index: the index of the item
 557  * @attribute: the attribute to query
 558  * @format_string: a #GVariant format string
 559  * @...: positional parameters, as per @format_string
 560  *
 561  * Queries item at position @item_index in @model for the attribute
 562  * specified by @attribute.
 563  *
 564  * If the attribute exists and matches the #GVariantType corresponding
 565  * to @format_string then @format_string is used to deconstruct the
 566  * value into the positional parameters and %TRUE is returned.
 567  *
 568  * If the attribute does not exist, or it does exist but has the wrong
 569  * type, then the positional parameters are ignored and %FALSE is
 570  * returned.
 571  *
 572  * This function is a mix of g_menu_model_get_item_attribute_value() and
 573  * g_variant_get(), followed by a g_variant_unref().  As such,
 574  * @format_string must make a complete copy of the data (since the
 575  * #GVariant may go away after the call to g_variant_unref()).  In
 576  * particular, no '&' characters are allowed in @format_string.
 577  *
 578  * Returns: %TRUE if the named attribute was found with the expected
 579  *     type
 580  *
 581  * Since: 2.32
 582  */
 583 gboolean
 584 g_menu_model_get_item_attribute (GMenuModel  *model,
 585                                  gint         item_index,
 586                                  const gchar *attribute,
 587                                  const gchar *format_string,
 588                                  ...)
 589 {
 590   GVariant *value;
 591   va_list ap;
 592
 593   value = g_menu_model_get_item_attribute_value (model, item_index, attribute, NULL);
 594
 595   if (value == NULL)
 596     return FALSE;
 597
 598   if (!g_variant_check_format_string (value, format_string, TRUE))
 599     {
 600       g_variant_unref (value);
 601       return FALSE;
 602     }
 603
 604   va_start (ap, format_string);
 605   g_variant_get_va (value, format_string, NULL, &ap);
 606   g_variant_unref (value);
 607   va_end (ap);
 608
 609   return TRUE;
 610 }
 611
 612 /**
 613  * g_menu_model_iterate_item_links:
 614  * @model: a #GMenuModel
 615  * @item_index: the index of the item
 616  *
 617  * Creates a #GMenuLinkIter to iterate over the links of the item at
 618  * position @item_index in @model.
 619  *
 620  * You must free the iterator with g_object_unref() when you are done.
 621  *
 622  * Returns: (transfer full): a new #GMenuLinkIter
 623  *
 624  * Since: 2.32
 625  */
 626 GMenuLinkIter *
 627 g_menu_model_iterate_item_links (GMenuModel *model,
 628                                  gint        item_index)
 629 {
 630   return G_MENU_MODEL_GET_CLASS (model)
 631     ->iterate_item_links (model, item_index);
 632 }
 633
 634 /**
 635  * g_menu_model_get_item_link:
 636  * @model: a #GMenuModel
 637  * @item_index: the index of the item
 638  * @link: the link to query
 639  *
 640  * Queries the item at position @item_index in @model for the link
 641  * specified by @link.
 642  *
 643  * If the link exists, the linked #GMenuModel is returned.  If the link
 644  * does not exist, %NULL is returned.
 645  *
 646  * Returns: (transfer full): the linked #GMenuModel, or %NULL
 647  *
 648  * Since: 2.32
 649  */
 650 GMenuModel *
 651 g_menu_model_get_item_link (GMenuModel *model,
 652                             gint        item_index,
 653                             const gchar *link)
 654 {
 655   return G_MENU_MODEL_GET_CLASS (model)
 656     ->get_item_link (model, item_index, link);
 657 }
 658
 659 /**
 660  * g_menu_model_items_changed:
 661  * @model: a #GMenuModel
 662  * @position: the position of the change
 663  * @removed: the number of items removed
 664  * @added: the number of items added
 665  *
 666  * Requests emission of the #GMenuModel::items-changed signal on @model.
 667  *
 668  * This function should never be called except by #GMenuModel
 669  * subclasses.  Any other calls to this function will very likely lead
 670  * to a violation of the interface of the model.
 671  *
 672  * The implementation should update its internal representation of the
 673  * menu before emitting the signal.  The implementation should further
 674  * expect to receive queries about the new state of the menu (and
 675  * particularly added menu items) while signal handlers are running.
 676  *
 677  * The implementation must dispatch this call directly from a mainloop
 678  * entry and not in response to calls -- particularly those from the
 679  * #GMenuModel API.  Said another way: the menu must not change while
 680  * user code is running without returning to the mainloop.
 681  *
 682  * Since: 2.32
 683  */
 684 void
 685 g_menu_model_items_changed (GMenuModel *model,
 686                             gint        position,
 687                             gint        removed,
 688                             gint        added)
 689 {
 690   g_signal_emit (model, g_menu_model_items_changed_signal, 0, position, removed, added);
 691 }
 692
 693 struct _GMenuAttributeIterPrivate
 694 {
 695   GQuark name;
 696   GVariant *value;
 697   gboolean valid;
 698 };
 699
 700 G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GMenuAttributeIter, g_menu_attribute_iter, G_TYPE_OBJECT)
 701
 702 /**
 703  * g_menu_attribute_iter_get_next:
 704  * @iter: a #GMenuAttributeIter
 705  * @out_name: (out) (optional) (transfer none): the type of the attribute
 706  * @value: (out) (optional) (transfer full): the attribute value
 707  *
 708  * This function combines g_menu_attribute_iter_next() with
 709  * g_menu_attribute_iter_get_name() and g_menu_attribute_iter_get_value().
 710  *
 711  * First the iterator is advanced to the next (possibly first) attribute.
 712  * If that fails, then %FALSE is returned and there are no other
 713  * effects.
 714  *
 715  * If successful, @name and @value are set to the name and value of the
 716  * attribute that has just been advanced to.  At this point,
 717  * g_menu_attribute_iter_get_name() and g_menu_attribute_iter_get_value() will
 718  * return the same values again.
 719  *
 720  * The value returned in @name remains valid for as long as the iterator
 721  * remains at the current position.  The value returned in @value must
 722  * be unreffed using g_variant_unref() when it is no longer in use.
 723  *
 724  * Returns: %TRUE on success, or %FALSE if there is no additional
 725  *     attribute
 726  *
 727  * Since: 2.32
 728  */
 729 gboolean
 730 g_menu_attribute_iter_get_next (GMenuAttributeIter  *iter,
 731                                 const gchar        **out_name,
 732                                 GVariant           **value)
 733 {
 734   const gchar *name;
 735
 736   if (iter->priv->value)
 737     {
 738       g_variant_unref (iter->priv->value);
 739       iter->priv->value = NULL;
 740     }
 741
 742   iter->priv->valid = G_MENU_ATTRIBUTE_ITER_GET_CLASS (iter)
 743     ->get_next (iter, &name, &iter->priv->value);
 744
 745   if (iter->priv->valid)
 746     {
 747       iter->priv->name = g_quark_from_string (name);
 748       if (out_name)
 749         *out_name = g_quark_to_string (iter->priv->name);
 750
 751       if (value)
 752         *value = g_variant_ref (iter->priv->value);
 753     }
 754
 755   return iter->priv->valid;
 756 }
 757
 758 /**
 759  * g_menu_attribute_iter_next:
 760  * @iter: a #GMenuAttributeIter
 761  *
 762  * Attempts to advance the iterator to the next (possibly first)
 763  * attribute.
 764  *
 765  * %TRUE is returned on success, or %FALSE if there are no more
 766  * attributes.
 767  *
 768  * You must call this function when you first acquire the iterator
 769  * to advance it to the first attribute (and determine if the first
 770  * attribute exists at all).
 771  *
 772  * Returns: %TRUE on success, or %FALSE when there are no more attributes
 773  *
 774  * Since: 2.32
 775  */
 776 gboolean
 777 g_menu_attribute_iter_next (GMenuAttributeIter *iter)
 778 {
 779   return g_menu_attribute_iter_get_next (iter, NULL, NULL);
 780 }
 781
 782 /**
 783  * g_menu_attribute_iter_get_name:
 784  * @iter: a #GMenuAttributeIter
 785  *
 786  * Gets the name of the attribute at the current iterator position, as
 787  * a string.
 788  *
 789  * The iterator is not advanced.
 790  *
 791  * Returns: the name of the attribute
 792  *
 793  * Since: 2.32
 794  */
 795 const gchar *
 796 g_menu_attribute_iter_get_name (GMenuAttributeIter *iter)
 797 {
 798   g_return_val_if_fail (iter->priv->valid, 0);
 799
 800   return g_quark_to_string (iter->priv->name);
 801 }
 802
 803 /**
 804  * g_menu_attribute_iter_get_value:
 805  * @iter: a #GMenuAttributeIter
 806  *
 807  * Gets the value of the attribute at the current iterator position.
 808  *
 809  * The iterator is not advanced.
 810  *
 811  * Returns: (transfer full): the value of the current attribute
 812  *
 813  * Since: 2.32
 814  */
 815 GVariant *
 816 g_menu_attribute_iter_get_value (GMenuAttributeIter *iter)
 817 {
 818   g_return_val_if_fail (iter->priv->valid, NULL);
 819
 820   return g_variant_ref (iter->priv->value);
 821 }
 822
 823 static void
 824 g_menu_attribute_iter_finalize (GObject *object)
 825 {
 826   GMenuAttributeIter *iter = G_MENU_ATTRIBUTE_ITER (object);
 827
 828   if (iter->priv->value)
 829     g_variant_unref (iter->priv->value);
 830
 831   G_OBJECT_CLASS (g_menu_attribute_iter_parent_class)
 832     ->finalize (object);
 833 }
 834
 835 static void
 836 g_menu_attribute_iter_init (GMenuAttributeIter *iter)
 837 {
 838   iter->priv = g_menu_attribute_iter_get_instance_private (iter);
 839 }
 840
 841 static void
 842 g_menu_attribute_iter_class_init (GMenuAttributeIterClass *class)
 843 {
 844   GObjectClass *object_class = G_OBJECT_CLASS (class);
 845
 846   object_class->finalize = g_menu_attribute_iter_finalize;
 847 }
 848
 849 struct _GMenuLinkIterPrivate
 850 {
 851   GQuark name;
 852   GMenuModel *value;
 853   gboolean valid;
 854 };
 855
 856 G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GMenuLinkIter, g_menu_link_iter, G_TYPE_OBJECT)
 857
 858 /**
 859  * g_menu_link_iter_get_next:
 860  * @iter: a #GMenuLinkIter
 861  * @out_link: (out) (optional) (transfer none): the name of the link
 862  * @value: (out) (optional) (transfer full): the linked #GMenuModel
 863  *
 864  * This function combines g_menu_link_iter_next() with
 865  * g_menu_link_iter_get_name() and g_menu_link_iter_get_value().
 866  *
 867  * First the iterator is advanced to the next (possibly first) link.
 868  * If that fails, then %FALSE is returned and there are no other effects.
 869  *
 870  * If successful, @out_link and @value are set to the name and #GMenuModel
 871  * of the link that has just been advanced to.  At this point,
 872  * g_menu_link_iter_get_name() and g_menu_link_iter_get_value() will return the
 873  * same values again.
 874  *
 875  * The value returned in @out_link remains valid for as long as the iterator
 876  * remains at the current position.  The value returned in @value must
 877  * be unreffed using g_object_unref() when it is no longer in use.
 878  *
 879  * Returns: %TRUE on success, or %FALSE if there is no additional link
 880  *
 881  * Since: 2.32
 882  */
 883 gboolean
 884 g_menu_link_iter_get_next (GMenuLinkIter  *iter,
 885                            const gchar   **out_link,
 886                            GMenuModel    **value)
 887 {
 888   const gchar *name;
 889
 890   if (iter->priv->value)
 891     {
 892       g_object_unref (iter->priv->value);
 893       iter->priv->value = NULL;
 894     }
 895
 896   iter->priv->valid = G_MENU_LINK_ITER_GET_CLASS (iter)
 897     ->get_next (iter, &name, &iter->priv->value);
 898
 899   if (iter->priv->valid)
 900     {
 901       g_assert (name != NULL);
 902
 903       iter->priv->name = g_quark_from_string (name);
 904       if (out_link)
 905         *out_link = g_quark_to_string (iter->priv->name);
 906
 907       if (value)
 908         *value = g_object_ref (iter->priv->value);
 909     }
 910
 911   return iter->priv->valid;
 912 }
 913
 914 /**
 915  * g_menu_link_iter_next:
 916  * @iter: a #GMenuLinkIter
 917  *
 918  * Attempts to advance the iterator to the next (possibly first)
 919  * link.
 920  *
 921  * %TRUE is returned on success, or %FALSE if there are no more links.
 922  *
 923  * You must call this function when you first acquire the iterator to
 924  * advance it to the first link (and determine if the first link exists
 925  * at all).
 926  *
 927  * Returns: %TRUE on success, or %FALSE when there are no more links
 928  *
 929  * Since: 2.32
 930  */
 931 gboolean
 932 g_menu_link_iter_next (GMenuLinkIter *iter)
 933 {
 934   return g_menu_link_iter_get_next (iter, NULL, NULL);
 935 }
 936
 937 /**
 938  * g_menu_link_iter_get_name:
 939  * @iter: a #GMenuLinkIter
 940  *
 941  * Gets the name of the link at the current iterator position.
 942  *
 943  * The iterator is not advanced.
 944  *
 945  * Returns: the type of the link
 946  *
 947  * Since: 2.32
 948  */
 949 const gchar *
 950 g_menu_link_iter_get_name (GMenuLinkIter *iter)
 951 {
 952   g_return_val_if_fail (iter->priv->valid, 0);
 953
 954   return g_quark_to_string (iter->priv->name);
 955 }
 956
 957 /**
 958  * g_menu_link_iter_get_value:
 959  * @iter: a #GMenuLinkIter
 960  *
 961  * Gets the linked #GMenuModel at the current iterator position.
 962  *
 963  * The iterator is not advanced.
 964  *
 965  * Returns: (transfer full): the #GMenuModel that is linked to
 966  *
 967  * Since: 2.32
 968  */
 969 GMenuModel *
 970 g_menu_link_iter_get_value (GMenuLinkIter *iter)
 971 {
 972   g_return_val_if_fail (iter->priv->valid, NULL);
 973
 974   return g_object_ref (iter->priv->value);
 975 }
 976
 977 static void
 978 g_menu_link_iter_finalize (GObject *object)
 979 {
 980   GMenuLinkIter *iter = G_MENU_LINK_ITER (object);
 981
 982   if (iter->priv->value)
 983     g_object_unref (iter->priv->value);
 984
 985   G_OBJECT_CLASS (g_menu_link_iter_parent_class)
 986     ->finalize (object);
 987 }
 988
 989 static void
 990 g_menu_link_iter_init (GMenuLinkIter *iter)
 991 {
 992   iter->priv = g_menu_link_iter_get_instance_private (iter);
 993 }
 994
 995 static void
 996 g_menu_link_iter_class_init (GMenuLinkIterClass *class)
 997 {
 998   GObjectClass *object_class = G_OBJECT_CLASS (class);
 999
1000   object_class->finalize = g_menu_link_iter_finalize;
1001 }