gio/gsimpleactiongroup.c

   1 /*
   2  * Copyright © 2010 Codethink Limited
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License as published
   6  * by the Free Software Foundation; either version 2 of the licence or (at
   7  * 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
  15  * Public 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  * Authors: Ryan Lortie <desrt@desrt.ca>
  20  */
  21
  22 #include "gsimpleactiongroup.h"
  23
  24 #include "gsimpleaction.h"
  25 #include "gaction.h"
  26
  27 /**
  28  * SECTION:gsimpleactiongroup
  29  * @title: GSimpleActionGroup
  30  * @short_description: A simple GActionGroup implementation
  31  *
  32  * #GSimpleActionGroup is a hash table filled with #GAction objects,
  33  * implementing the #GActionGroup interface.
  34  **/
  35
  36 struct _GSimpleActionGroupPrivate
  37 {
  38   GHashTable *table;  /* string -> GAction */
  39 };
  40
  41 static void g_simple_action_group_iface_init (GActionGroupInterface *);
  42 G_DEFINE_TYPE_WITH_CODE (GSimpleActionGroup,
  43   g_simple_action_group, G_TYPE_OBJECT,
  44   G_IMPLEMENT_INTERFACE (G_TYPE_ACTION_GROUP,
  45     g_simple_action_group_iface_init))
  46
  47 static gchar **
  48 g_simple_action_group_list_actions (GActionGroup *group)
  49 {
  50   GSimpleActionGroup *simple = G_SIMPLE_ACTION_GROUP (group);
  51   GHashTableIter iter;
  52   gint n, i = 0;
  53   gchar **keys;
  54   gpointer key;
  55
  56   n = g_hash_table_size (simple->priv->table);
  57   keys = g_new (gchar *, n + 1);
  58
  59   g_hash_table_iter_init (&iter, simple->priv->table);
  60   while (g_hash_table_iter_next (&iter, &key, NULL))
  61     keys[i++] = g_strdup (key);
  62   g_assert_cmpint (i, ==, n);
  63   keys[n] = NULL;
  64
  65   return keys;
  66 }
  67
  68 static gboolean
  69 g_simple_action_group_query_action (GActionGroup        *group,
  70                                     const gchar         *action_name,
  71                                     gboolean            *enabled,
  72                                     const GVariantType **parameter_type,
  73                                     const GVariantType **state_type,
  74                                     GVariant           **state_hint,
  75                                     GVariant           **state)
  76 {
  77   GSimpleActionGroup *simple = G_SIMPLE_ACTION_GROUP (group);
  78   GAction *action;
  79
  80   action = g_hash_table_lookup (simple->priv->table, action_name);
  81
  82   if (action == NULL)
  83     return FALSE;
  84
  85   if (enabled)
  86     *enabled = g_action_get_enabled (action);
  87
  88   if (parameter_type)
  89     *parameter_type = g_action_get_parameter_type (action);
  90
  91   if (state_type)
  92     *state_type = g_action_get_state_type (action);
  93
  94   if (state_hint)
  95     *state_hint = g_action_get_state_hint (action);
  96
  97   if (state)
  98     *state = g_action_get_state (action);
  99
 100   return TRUE;
 101 }
 102
 103 static void
 104 g_simple_action_group_change_state (GActionGroup *group,
 105                                     const gchar  *action_name,
 106                                     GVariant     *value)
 107 {
 108   GSimpleActionGroup *simple = G_SIMPLE_ACTION_GROUP (group);
 109   GAction *action;
 110
 111   action = g_hash_table_lookup (simple->priv->table, action_name);
 112
 113   if (action == NULL)
 114     return;
 115
 116   g_action_change_state (action, value);
 117 }
 118
 119 static void
 120 g_simple_action_group_activate (GActionGroup *group,
 121                                 const gchar  *action_name,
 122                                 GVariant     *parameter)
 123 {
 124   GSimpleActionGroup *simple = G_SIMPLE_ACTION_GROUP (group);
 125   GAction *action;
 126
 127   action = g_hash_table_lookup (simple->priv->table, action_name);
 128
 129   if (action == NULL)
 130     return;
 131
 132   g_action_activate (action, parameter);
 133 }
 134
 135 static void
 136 action_enabled_notify (GAction     *action,
 137                        GParamSpec  *pspec,
 138                        gpointer     user_data)
 139 {
 140   g_action_group_action_enabled_changed (user_data,
 141                                          g_action_get_name (action),
 142                                          g_action_get_enabled (action));
 143 }
 144
 145 static void
 146 action_state_notify (GAction    *action,
 147                      GParamSpec *pspec,
 148                      gpointer    user_data)
 149 {
 150   GVariant *value;
 151
 152   value = g_action_get_state (action);
 153   g_action_group_action_state_changed (user_data,
 154                                        g_action_get_name (action),
 155                                        value);
 156   g_variant_unref (value);
 157 }
 158
 159 static void
 160 g_simple_action_group_disconnect (gpointer key,
 161                                   gpointer value,
 162                                   gpointer user_data)
 163 {
 164   g_signal_handlers_disconnect_by_func (value, action_enabled_notify,
 165                                         user_data);
 166   g_signal_handlers_disconnect_by_func (value, action_state_notify,
 167                                         user_data);
 168 }
 169
 170 static void
 171 g_simple_action_group_finalize (GObject *object)
 172 {
 173   GSimpleActionGroup *simple = G_SIMPLE_ACTION_GROUP (object);
 174
 175   g_hash_table_foreach (simple->priv->table,
 176                         g_simple_action_group_disconnect,
 177                         simple);
 178   g_hash_table_unref (simple->priv->table);
 179
 180   G_OBJECT_CLASS (g_simple_action_group_parent_class)
 181     ->finalize (object);
 182 }
 183
 184 static void
 185 g_simple_action_group_init (GSimpleActionGroup *simple)
 186 {
 187   simple->priv = G_TYPE_INSTANCE_GET_PRIVATE (simple,
 188                                               G_TYPE_SIMPLE_ACTION_GROUP,
 189                                               GSimpleActionGroupPrivate);
 190   simple->priv->table = g_hash_table_new_full (g_str_hash, g_str_equal,
 191                                                g_free, g_object_unref);
 192 }
 193
 194 static void
 195 g_simple_action_group_class_init (GSimpleActionGroupClass *class)
 196 {
 197   GObjectClass *object_class = G_OBJECT_CLASS (class);
 198
 199   object_class->finalize = g_simple_action_group_finalize;
 200
 201   g_type_class_add_private (class, sizeof (GSimpleActionGroupPrivate));
 202 }
 203
 204 static void
 205 g_simple_action_group_iface_init (GActionGroupInterface *iface)
 206 {
 207   iface->list_actions = g_simple_action_group_list_actions;
 208   iface->query_action = g_simple_action_group_query_action;
 209   iface->change_action_state = g_simple_action_group_change_state;
 210   iface->activate_action = g_simple_action_group_activate;
 211 }
 212
 213 /**
 214  * g_simple_action_group_new:
 215  *
 216  * Creates a new, empty, #GSimpleActionGroup.
 217  *
 218  * Returns: a new #GSimpleActionGroup
 219  *
 220  * Since: 2.28
 221  **/
 222 GSimpleActionGroup *
 223 g_simple_action_group_new (void)
 224 {
 225   return g_object_new (G_TYPE_SIMPLE_ACTION_GROUP, NULL);
 226 }
 227
 228 /**
 229  * g_simple_action_group_lookup:
 230  * @simple: a #GSimpleActionGroup
 231  * @action_name: the name of an action
 232  *
 233  * Looks up the action with the name @action_name in the group.
 234  *
 235  * If no such action exists, returns %NULL.
 236  *
 237  * Returns: (transfer none): a #GAction, or %NULL
 238  *
 239  * Since: 2.28
 240  **/
 241 GAction *
 242 g_simple_action_group_lookup (GSimpleActionGroup *simple,
 243                               const gchar        *action_name)
 244 {
 245   g_return_val_if_fail (G_IS_SIMPLE_ACTION_GROUP (simple), NULL);
 246
 247   return g_hash_table_lookup (simple->priv->table, action_name);
 248 }
 249
 250 /**
 251  * g_simple_action_group_insert:
 252  * @simple: a #GSimpleActionGroup
 253  * @action: a #GAction
 254  *
 255  * Adds an action to the action group.
 256  *
 257  * If the action group already contains an action with the same name as
 258  * @action then the old action is dropped from the group.
 259  *
 260  * The action group takes its own reference on @action.
 261  *
 262  * Since: 2.28
 263  **/
 264 void
 265 g_simple_action_group_insert (GSimpleActionGroup *simple,
 266                               GAction            *action)
 267 {
 268   const gchar *action_name;
 269   GAction *old_action;
 270
 271   g_return_if_fail (G_IS_SIMPLE_ACTION_GROUP (simple));
 272   g_return_if_fail (G_IS_ACTION (action));
 273
 274   action_name = g_action_get_name (action);
 275   old_action = g_hash_table_lookup (simple->priv->table, action_name);
 276
 277   if (old_action != action)
 278     {
 279       if (old_action != NULL)
 280         {
 281           g_action_group_action_removed (G_ACTION_GROUP (simple),
 282                                          action_name);
 283           g_simple_action_group_disconnect (NULL, old_action, simple);
 284         }
 285
 286       g_signal_connect (action, "notify::enabled",
 287                         G_CALLBACK (action_enabled_notify), simple);
 288
 289       if (g_action_get_state_type (action) != NULL)
 290         g_signal_connect (action, "notify::state",
 291                           G_CALLBACK (action_state_notify), simple);
 292
 293       g_hash_table_insert (simple->priv->table,
 294                            g_strdup (action_name),
 295                            g_object_ref (action));
 296
 297       g_action_group_action_added (G_ACTION_GROUP (simple), action_name);
 298     }
 299 }
 300
 301 /**
 302  * g_simple_action_group_remove:
 303  * @simple: a #GSimpleActionGroup
 304  * @action_name: the name of the action
 305  *
 306  * Removes the named action from the action group.
 307  *
 308  * If no action of this name is in the group then nothing happens.
 309  *
 310  * Since: 2.28
 311  **/
 312 void
 313 g_simple_action_group_remove (GSimpleActionGroup *simple,
 314                               const gchar        *action_name)
 315 {
 316   GAction *action;
 317
 318   g_return_if_fail (G_IS_SIMPLE_ACTION_GROUP (simple));
 319
 320   action = g_hash_table_lookup (simple->priv->table, action_name);
 321
 322   if (action != NULL)
 323     {
 324       g_action_group_action_removed (G_ACTION_GROUP (simple), action_name);
 325       g_simple_action_group_disconnect (NULL, action, simple);
 326       g_hash_table_remove (simple->priv->table, action_name);
 327     }
 328 }
 329
 330 /**
 331  * GActionEntry:
 332  * @name: the name of the action
 333  * @activate: the callback to connect to the "activate" signal of the
 334  *            action
 335  * @parameter_type: the type of the parameter that must be passed to the
 336  *                  activate function for this action, given as a single
 337  *                  GVariant type string (or %NULL for no parameter)
 338  * @state: the initial state for this action, given in GVariant text
 339  *         format.  The state is parsed with no extra type information,
 340  *         so type tags must be added to the string if they are
 341  *         necessary.
 342  * @change_state: the callback to connect to the "change-state" signal
 343  *                of the action
 344  *
 345  * This struct defines a single action.  It is for use with
 346  * g_simple_action_group_add_entries().
 347  *
 348  * The order of the items in the structure are intended to reflect
 349  * frequency of use.  It is permissible to use an incomplete initialiser
 350  * in order to leave some of the later values as %NULL.  All values
 351  * after @name are optional.  Additional optional fields may be added in
 352  * the future.
 353  *
 354  * See g_simple_action_group_add_entries() for an example.
 355  **/
 356
 357 /**
 358  * g_simple_action_group_add_entries:
 359  * @simple: a #GSimpleActionGroup
 360  * @entries: a pointer to the first item in an array of #GActionEntry
 361  *           structs
 362  * @n_entries: the length of @entries, or -1
 363  * @user_data: the user data for signal connections
 364  *
 365  * A convenience function for creating multiple #GSimpleAction instances
 366  * and adding them to the action group.
 367  *
 368  * Each action is constructed as per one #GActionEntry.
 369  *
 370  * <example>
 371  * <title>Using g_simple_action_group_add_entries()</title>
 372  * <programlisting>
 373  * static void
 374  * activate_quit (GSimpleAction *simple,
 375  *                GVariant      *parameter,
 376  *                gpointer       user_data)
 377  * {
 378  *   exit (0);
 379  * }
 380  *
 381  * static void
 382  * activate_print_string (GSimpleAction *simple,
 383  *                        GVariant      *parameter,
 384  *                        gpointer       user_data)
 385  * {
 386  *   g_print ("%s\n", g_variant_get_string (parameter, NULL));
 387  * }
 388  *
 389  * static GActionGroup *
 390  * create_action_group (void)
 391  * {
 392  *   const GActionEntry entries[] = {
 393  *     { "quit",         activate_quit              },
 394  *     { "print-string", activate_print_string, "s" }
 395  *   };
 396  *   GSimpleActionGroup *group;
 397  *
 398  *   group = g_simple_action_group_new ();
 399  *   g_simple_action_group_add_entries (group, entries, G_N_ELEMENTS (entries), NULL);
 400  *
 401  *   return G_ACTION_GROUP (group);
 402  * }
 403  * </programlisting>
 404  * </example>
 405  *
 406  * Since: 2.30
 407  **/
 408 void
 409 g_simple_action_group_add_entries (GSimpleActionGroup *simple,
 410                                    const GActionEntry *entries,
 411                                    gint                n_entries,
 412                                    gpointer            user_data)
 413 {
 414   gint i;
 415
 416   g_return_if_fail (G_IS_SIMPLE_ACTION_GROUP (simple));
 417   g_return_if_fail (entries != NULL || n_entries == 0);
 418
 419   for (i = 0; n_entries == -1 ? entries[i].name != NULL : i < n_entries; i++)
 420     {
 421       const GActionEntry *entry = &entries[i];
 422       const GVariantType *parameter_type;
 423       GSimpleAction *action;
 424
 425       if (entry->parameter_type)
 426         {
 427           if (!g_variant_type_string_is_valid (entry->parameter_type))
 428             {
 429               g_critical ("g_simple_action_group_add_entries: the type "
 430                           "string '%s' given as the parameter type for "
 431                           "action '%s' is not a valid GVariant type "
 432                           "string.  This action will not be added.",
 433                           entry->parameter_type, entry->name);
 434               return;
 435             }
 436
 437           parameter_type = G_VARIANT_TYPE (entry->parameter_type);
 438         }
 439       else
 440         parameter_type = NULL;
 441
 442       if (entry->state)
 443         {
 444           GError *error = NULL;
 445           GVariant *state;
 446
 447           state = g_variant_parse (NULL, entry->state, NULL, NULL, &error);
 448           if (state == NULL)
 449             {
 450               g_critical ("g_simple_action_group_add_entries: GVariant could "
 451                           "not parse the state value given for action '%s' "
 452                           "('%s'): %s.  This action will not be added.",
 453                           entry->name, entry->state, error->message);
 454               g_error_free (error);
 455               continue;
 456             }
 457
 458           action = g_simple_action_new_stateful (entry->name,
 459                                                  parameter_type,
 460                                                  state);
 461
 462           g_variant_unref (state);
 463         }
 464       else
 465         {
 466           action = g_simple_action_new (entry->name,
 467                                         parameter_type);
 468         }
 469
 470       if (entry->activate != NULL)
 471         g_signal_connect (action, "activate",
 472                           G_CALLBACK (entry->activate), user_data);
 473
 474       if (entry->change_state != NULL)
 475         g_signal_connect (action, "change-state",
 476                           G_CALLBACK (entry->change_state), user_data);
 477
 478       g_simple_action_group_insert (simple, G_ACTION (action));
 479       g_object_unref (action);
 480     }
 481 }