gio/gactiongroup.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 "config.h"
  23 #include "gactiongroup.h"
  24 #include "gaction.h"
  25 #include "gio-marshal.h"
  26 #include "glibintl.h"
  27
  28 /**
  29  * SECTION:gactiongroup
  30  * @title: GActionGroup
  31  * @short_description: A group of actions
  32  *
  33  * #GActionGroup represents a group of actions.
  34  *
  35  * Each action in the group has a unique name (which is a string).  All
  36  * method calls, except g_action_group_list_actions() take the name of
  37  * an action as an argument.
  38  *
  39  * The #GActionGroup API is meant to be the 'public' API to the action
  40  * group.  The calls here are exactly the interaction that 'external
  41  * forces' (eg: UI, incoming D-Bus messages, etc.) are supposed to have
  42  * with actions.  'Internal' APIs (ie: ones meant only to be accessed by
  43  * the action group implementation) are found on subclasses.  This is
  44  * why you will find -- for example -- g_action_group_get_enabled() but
  45  * not an equivalent <function>set()</function> call.
  46  *
  47  * Signals are emitted on the action group in response to state changes
  48  * on individual actions.
  49  **/
  50
  51 G_DEFINE_INTERFACE (GActionGroup, g_action_group, G_TYPE_OBJECT)
  52
  53 enum
  54 {
  55   SIGNAL_ACTION_ADDED,
  56   SIGNAL_ACTION_REMOVED,
  57   SIGNAL_ACTION_ENABLED_CHANGED,
  58   SIGNAL_ACTION_STATE_CHANGED,
  59   NR_SIGNALS
  60 };
  61
  62 static guint g_action_group_signals[NR_SIGNALS];
  63
  64 static void
  65 g_action_group_default_init (GActionGroupInterface *class)
  66 {
  67   /**
  68    * GActionGroup::action-added:
  69    * @action_group: the #GActionGroup that changed
  70    * @action_name: the name of the action in @action_group
  71    *
  72    * Signals that a new action was just added to the group.  This signal
  73    * is emitted after the action has been added and is now visible.
  74    *
  75    * Since: 2.28
  76    **/
  77   g_action_group_signals[SIGNAL_ACTION_ADDED] =
  78     g_signal_new (I_("action-added"),
  79                   G_TYPE_ACTION_GROUP,
  80                   G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
  81                   G_STRUCT_OFFSET (GActionGroupInterface, action_added),
  82                   NULL, NULL,
  83                   g_cclosure_marshal_VOID__STRING,
  84                   G_TYPE_NONE, 1,
  85                   G_TYPE_STRING);
  86
  87   /**
  88    * GActionGroup::action-removed:
  89    * @action_group: the #GActionGroup that changed
  90    * @action_name: the name of the action in @action_group
  91    *
  92    * Signals that an action is just about to be removed from the group.
  93    * This signal is emitted before the action is removed, so the action
  94    * is still visible and can be queried from the signal handler.
  95    *
  96    * Since: 2.28
  97    **/
  98   g_action_group_signals[SIGNAL_ACTION_REMOVED] =
  99     g_signal_new (I_("action-removed"),
 100                   G_TYPE_ACTION_GROUP,
 101                   G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
 102                   G_STRUCT_OFFSET (GActionGroupInterface, action_removed),
 103                   NULL, NULL,
 104                   g_cclosure_marshal_VOID__STRING,
 105                   G_TYPE_NONE, 1,
 106                   G_TYPE_STRING);
 107
 108
 109   /**
 110    * GActionGroup::action-enabled-changed:
 111    * @action_group: the #GActionGroup that changed
 112    * @action_name: the name of the action in @action_group
 113    * @enabled: whether the action is enabled or not
 114    *
 115    * Signals that the enabled status of the named action has changed.
 116    *
 117    * Since: 2.28
 118    **/
 119   g_action_group_signals[SIGNAL_ACTION_ENABLED_CHANGED] =
 120     g_signal_new (I_("action-enabled-changed"),
 121                   G_TYPE_ACTION_GROUP,
 122                   G_SIGNAL_RUN_LAST | G_SIGNAL_DETAILED,
 123                   G_STRUCT_OFFSET (GActionGroupInterface,
 124                                    action_enabled_changed),
 125                   NULL, NULL,
 126                   _gio_marshal_VOID__STRING_BOOLEAN,
 127                   G_TYPE_NONE, 2,
 128                   G_TYPE_STRING,
 129                   G_TYPE_BOOLEAN);
 130
 131   /**
 132    * GActionGroup::action-state-changed:
 133    * @action_group: the #GActionGroup that changed
 134    * @action_name: the name of the action in @action_group
 135    * @value: the new value of the state
 136    *
 137    * Signals that the state of the named action has changed.
 138    *
 139    * Since: 2.28
 140    **/
 141   g_action_group_signals[SIGNAL_ACTION_STATE_CHANGED] =
 142     g_signal_new (I_("action-state-changed"),
 143                   G_TYPE_ACTION_GROUP,
 144                   G_SIGNAL_RUN_LAST |
 145                   G_SIGNAL_DETAILED |
 146                   G_SIGNAL_MUST_COLLECT,
 147                   G_STRUCT_OFFSET (GActionGroupInterface,
 148                                    action_state_changed),
 149                   NULL, NULL,
 150                   _gio_marshal_VOID__STRING_VARIANT,
 151                   G_TYPE_NONE, 2,
 152                   G_TYPE_STRING,
 153                   G_TYPE_VARIANT);
 154 }
 155
 156 /**
 157  * g_action_group_list_actions:
 158  * @action_group: a #GActionGroup
 159  *
 160  * Lists the actions contained within @action_group.
 161  *
 162  * The caller is responsible for freeing the list with g_strfreev() when
 163  * it is no longer required.
 164  *
 165  * Returns: (transfer full): a %NULL-terminated array of the names of the
 166  * actions in the groupb
 167  *
 168  * Since: 2.28
 169  **/
 170 gchar **
 171 g_action_group_list_actions (GActionGroup *action_group)
 172 {
 173   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), NULL);
 174
 175   return G_ACTION_GROUP_GET_IFACE (action_group)
 176     ->list_actions (action_group);
 177 }
 178
 179 /**
 180  * g_action_group_has_action:
 181  * @action_group: a #GActionGroup
 182  * @action_name: the name of the action to check for
 183  *
 184  * Checks if the named action exists within @action_group.
 185  *
 186  * Returns: whether the named action exists
 187  *
 188  * Since: 2.28
 189  **/
 190 gboolean
 191 g_action_group_has_action (GActionGroup *action_group,
 192                            const gchar  *action_name)
 193 {
 194   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), FALSE);
 195
 196   return G_ACTION_GROUP_GET_IFACE (action_group)
 197     ->has_action (action_group, action_name);
 198 }
 199
 200 /**
 201  * g_action_group_get_action_parameter_type:
 202  * @action_group: a #GActionGroup
 203  * @action_name: the name of the action to query
 204  *
 205  * Queries the type of the parameter that must be given when activating
 206  * the named action within @action_group.
 207  *
 208  * When activating the action using g_action_group_activate(), the
 209  * #GVariant given to that function must be of the type returned by this
 210  * function.
 211  *
 212  * In the case that this function returns %NULL, you must not give any
 213  * #GVariant, but %NULL instead.
 214  *
 215  * The parameter type of a particular action will never change but it is
 216  * possible for an action to be removed and for a new action to be added
 217  * with the same name but a different parameter type.
 218  *
 219  * Return value: the parameter type
 220  *
 221  * Since: 2.28
 222  **/
 223 const GVariantType *
 224 g_action_group_get_action_parameter_type (GActionGroup *action_group,
 225                                           const gchar  *action_name)
 226 {
 227   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), NULL);
 228
 229   return G_ACTION_GROUP_GET_IFACE (action_group)
 230     ->get_action_parameter_type (action_group, action_name);
 231 }
 232
 233 /**
 234  * g_action_group_get_action_state_type:
 235  * @action_group: a #GActionGroup
 236  * @action_name: the name of the action to query
 237  *
 238  * Queries the type of the state of the named action within
 239  * @action_group.
 240  *
 241  * If the action is stateful then this function returns the
 242  * #GVariantType of the state.  All calls to g_action_group_set_state()
 243  * must give a #GVariant of this type and g_action_group_get_state()
 244  * will return a #GVariant of the same type.
 245  *
 246  * If the action is not stateful then this function will return %NULL.
 247  * In that case, g_action_group_get_state() will return %NULL and you
 248  * must not call g_action_group_set_state().
 249  *
 250  * The state type of a particular action will never change but it is
 251  * possible for an action to be removed and for a new action to be added
 252  * with the same name but a different state type.
 253  *
 254  * Returns: (transfer full): the state type, if the action is stateful
 255  *
 256  * Since: 2.28
 257  **/
 258 const GVariantType *
 259 g_action_group_get_action_state_type (GActionGroup *action_group,
 260                                       const gchar  *action_name)
 261 {
 262   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), NULL);
 263
 264   return G_ACTION_GROUP_GET_IFACE (action_group)
 265     ->get_action_state_type (action_group, action_name);
 266 }
 267
 268 /**
 269  * g_action_group_get_action_state_hint:
 270  * @action_group: a #GActionGroup
 271  * @action_name: the name of the action to query
 272  *
 273  * Requests a hint about the valid range of values for the state of the
 274  * named action within @action_group.
 275  *
 276  * If %NULL is returned it either means that the action is not stateful
 277  * or that there is no hint about the valid range of values for the
 278  * state of the action.
 279  *
 280  * If a #GVariant array is returned then each item in the array is a
 281  * possible value for the state.  If a #GVariant pair (ie: two-tuple) is
 282  * returned then the tuple specifies the inclusive lower and upper bound
 283  * of valid values for the state.
 284  *
 285  * In any case, the information is merely a hint.  It may be possible to
 286  * have a state value outside of the hinted range and setting a value
 287  * within the range may fail.
 288  *
 289  * The return value (if non-%NULL) should be freed with
 290  * g_variant_unref() when it is no longer required.
 291  *
 292  * Return value: (transfer full): the state range hint
 293  *
 294  * Since: 2.28
 295  **/
 296 GVariant *
 297 g_action_group_get_action_state_hint (GActionGroup *action_group,
 298                                       const gchar  *action_name)
 299 {
 300   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), NULL);
 301
 302   return G_ACTION_GROUP_GET_IFACE (action_group)
 303     ->get_action_state_hint (action_group, action_name);
 304 }
 305
 306 /**
 307  * g_action_group_get_action_enabled:
 308  * @action_group: a #GActionGroup
 309  * @action_name: the name of the action to query
 310  *
 311  * Checks if the named action within @action_group is currently enabled.
 312  *
 313  * An action must be enabled in order to be activated or in order to
 314  * have its state changed from outside callers.
 315  *
 316  * Return value: whether or not the action is currently enabled
 317  *
 318  * Since: 2.28
 319  **/
 320 gboolean
 321 g_action_group_get_action_enabled (GActionGroup *action_group,
 322                                    const gchar  *action_name)
 323 {
 324   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), FALSE);
 325
 326   return G_ACTION_GROUP_GET_IFACE (action_group)
 327     ->get_action_enabled (action_group, action_name);
 328 }
 329
 330 /**
 331  * g_action_group_get_action_state:
 332  * @action_group: a #GActionGroup
 333  * @action_name: the name of the action to query
 334  *
 335  * Queries the current state of the named action within @action_group.
 336  *
 337  * If the action is not stateful then %NULL will be returned.  If the
 338  * action is stateful then the type of the return value is the type
 339  * given by g_action_group_get_state_type().
 340  *
 341  * The return value (if non-%NULL) should be freed with
 342  * g_variant_unref() when it is no longer required.
 343  *
 344  * Return value: (allow-none): the current state of the action
 345  *
 346  * Since: 2.28
 347  **/
 348 GVariant *
 349 g_action_group_get_action_state (GActionGroup *action_group,
 350                                  const gchar  *action_name)
 351 {
 352   g_return_val_if_fail (G_IS_ACTION_GROUP (action_group), NULL);
 353
 354   return G_ACTION_GROUP_GET_IFACE (action_group)
 355     ->get_action_state (action_group, action_name);
 356 }
 357
 358 /**
 359  * g_action_group_change_action_state:
 360  * @action_group: a #GActionGroup
 361  * @action_name: the name of the action to request the change on
 362  * @value: the new state
 363  *
 364  * Request for the state of the named action within @action_group to be
 365  * changed to @value.
 366  *
 367  * The action must be stateful and @value must be of the correct type.
 368  * See g_action_group_get_state_type().
 369  *
 370  * This call merely requests a change.  The action may refuse to change
 371  * its state or may change its state to something other than @value.
 372  * See g_action_group_get_state_hint().
 373  *
 374  * If the @value GVariant is floating, it is consumed.
 375  *
 376  * Since: 2.28
 377  **/
 378 void
 379 g_action_group_change_action_state (GActionGroup *action_group,
 380                                     const gchar  *action_name,
 381                                     GVariant     *value)
 382 {
 383   g_return_if_fail (G_IS_ACTION_GROUP (action_group));
 384   g_return_if_fail (action_name != NULL);
 385   g_return_if_fail (value != NULL);
 386
 387   G_ACTION_GROUP_GET_IFACE (action_group)
 388     ->change_action_state (action_group, action_name, value);
 389 }
 390
 391 /**
 392  * g_action_group_activate_action:
 393  * @action_group: a #GActionGroup
 394  * @action_name: the name of the action to activate
 395  * @parameter: (allow-none): parameters to the activation
 396  *
 397  * Activate the named action within @action_group.
 398  *
 399  * If the action is expecting a parameter, then the correct type of
 400  * parameter must be given as @parameter.  If the action is expecting no
 401  * parameters then @parameter must be %NULL.  See
 402  * g_action_group_get_parameter_type().
 403  *
 404  * Since: 2.28
 405  **/
 406 void
 407 g_action_group_activate_action (GActionGroup *action_group,
 408                                 const gchar  *action_name,
 409                                 GVariant     *parameter)
 410 {
 411   g_return_if_fail (G_IS_ACTION_GROUP (action_group));
 412   g_return_if_fail (action_name != NULL);
 413
 414   G_ACTION_GROUP_GET_IFACE (action_group)
 415     ->activate_action (action_group, action_name, parameter);
 416 }
 417
 418 /**
 419  * g_action_group_action_added:
 420  * @action_group: a #GActionGroup
 421  * @action_name: the name of an action in the group
 422  *
 423  * Emits the #GActionGroup::action-added signal on @action_group.
 424  *
 425  * This function should only be called by #GActionGroup implementations.
 426  *
 427  * Since: 2.28
 428  **/
 429 void
 430 g_action_group_action_added (GActionGroup *action_group,
 431                              const gchar  *action_name)
 432 {
 433   g_return_if_fail (G_IS_ACTION_GROUP (action_group));
 434   g_return_if_fail (action_name != NULL);
 435
 436   g_signal_emit (action_group,
 437                  g_action_group_signals[SIGNAL_ACTION_ADDED],
 438                  g_quark_try_string (action_name),
 439                  action_name);
 440 }
 441
 442 /**
 443  * g_action_group_action_removed:
 444  * @action_group: a #GActionGroup
 445  * @action_name: the name of an action in the group
 446  *
 447  * Emits the #GActionGroup::action-removed signal on @action_group.
 448  *
 449  * This function should only be called by #GActionGroup implementations.
 450  *
 451  * Since: 2.28
 452  **/
 453 void
 454 g_action_group_action_removed (GActionGroup *action_group,
 455                                const gchar  *action_name)
 456 {
 457   g_return_if_fail (G_IS_ACTION_GROUP (action_group));
 458   g_return_if_fail (action_name != NULL);
 459
 460   g_signal_emit (action_group,
 461                  g_action_group_signals[SIGNAL_ACTION_REMOVED],
 462                  g_quark_try_string (action_name),
 463                  action_name);
 464 }
 465
 466 /**
 467  * g_action_group_action_enabled_changed:
 468  * @action_group: a #GActionGroup
 469  * @action_name: the name of an action in the group
 470  * @enabled: whether or not the action is now enabled
 471  *
 472  * Emits the #GActionGroup::action-enabled-changed signal on @action_group.
 473  *
 474  * This function should only be called by #GActionGroup implementations.
 475  *
 476  * Since: 2.28
 477  **/
 478 void
 479 g_action_group_action_enabled_changed (GActionGroup *action_group,
 480                                        const gchar  *action_name,
 481                                        gboolean      enabled)
 482 {
 483   g_return_if_fail (G_IS_ACTION_GROUP (action_group));
 484   g_return_if_fail (action_name != NULL);
 485
 486   enabled = !!enabled;
 487
 488   g_signal_emit (action_group,
 489                  g_action_group_signals[SIGNAL_ACTION_ENABLED_CHANGED],
 490                  g_quark_try_string (action_name),
 491                  action_name,
 492                  enabled);
 493 }
 494
 495 /**
 496  * g_action_group_action_state_changed:
 497  * @action_group: a #GActionGroup
 498  * @action_name: the name of an action in the group
 499  * @state: the new state of the named action
 500  *
 501  * Emits the #GActionGroup::action-state-changed signal on @action_group.
 502  *
 503  * This function should only be called by #GActionGroup implementations.
 504  *
 505  * Since: 2.28
 506  **/
 507 void
 508 g_action_group_action_state_changed (GActionGroup *action_group,
 509                                      const gchar  *action_name,
 510                                      GVariant     *state)
 511 {
 512   g_return_if_fail (G_IS_ACTION_GROUP (action_group));
 513   g_return_if_fail (action_name != NULL);
 514
 515   g_signal_emit (action_group,
 516                  g_action_group_signals[SIGNAL_ACTION_STATE_CHANGED],
 517                  g_quark_try_string (action_name),
 518                  action_name,
 519                  state);
 520 }