## GtkActionGroup GtkActionGroup — A group of actions |

## Synopsis

    #include <gtk/gtk.h>

    struct              GtkActionGroup;
    GtkActionGroup *    gtk_action_group_new                (const gchar *name);
    const gchar *       gtk_action_group_get_name           (GtkActionGroup *action_group);
    gboolean            gtk_action_group_get_sensitive      (GtkActionGroup *action_group);
    void                gtk_action_group_set_sensitive      (GtkActionGroup *action_group,
                                                             gboolean sensitive);
    gboolean            gtk_action_group_get_visible        (GtkActionGroup *action_group);
    void                gtk_action_group_set_visible        (GtkActionGroup *action_group,
                                                             gboolean visible);
    GtkAccelGroup *     gtk_action_group_get_accel_group    (GtkActionGroup *action_group);
    void                gtk_action_group_set_accel_group    (GtkActionGroup *action_group,
                                                             GtkAccelGroup *accel_group);
    GtkAction *         gtk_action_group_get_action         (GtkActionGroup *action_group,
                                                             const gchar *action_name);
    GList *             gtk_action_group_list_actions       (GtkActionGroup *action_group);
    void                gtk_action_group_add_action         (GtkActionGroup *action_group,
                                                             GtkAction *action);
    void                gtk_action_group_add_action_with_accel
                                                            (GtkActionGroup *action_group,
                                                             GtkAction *action,
                                                             const gchar *accelerator);
    void                gtk_action_group_remove_action      (GtkActionGroup *action_group,
                                                             GtkAction *action);
    struct              GtkActionEntry;
    void                gtk_action_group_add_actions        (GtkActionGroup *action_group,
                                                             const GtkActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data);
    void                gtk_action_group_add_actions_full   (GtkActionGroup *action_group,
                                                             const GtkActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data,
                                                             GDestroyNotify destroy);
    struct              GtkToggleActionEntry;
    void                gtk_action_group_add_toggle_actions (GtkActionGroup *action_group,
                                                             const GtkToggleActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data);
    void                gtk_action_group_add_toggle_actions_full
                                                            (GtkActionGroup *action_group,
                                                             const GtkToggleActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data,
                                                             GDestroyNotify destroy);
    struct              GtkRadioActionEntry;
    void                gtk_action_group_add_radio_actions  (GtkActionGroup *action_group,
                                                             const GtkRadioActionEntry *entries,
                                                             guint n_entries,
                                                             gint value,
                                                             GCallback on_change,
                                                             gpointer user_data);
    void                gtk_action_group_add_radio_actions_full
                                                            (GtkActionGroup *action_group,
                                                             const GtkRadioActionEntry *entries,
                                                             guint n_entries,
                                                             gint value,
                                                             GCallback on_change,
                                                             gpointer user_data,
                                                             GDestroyNotify destroy);
    gchar *             (*GtkTranslateFunc)                 (const gchar *path,
                                                             gpointer func_data);
    void                gtk_action_group_set_translate_func (GtkActionGroup *action_group,
                                                             GtkTranslateFunc func,
                                                             gpointer data,
                                                             GDestroyNotify notify);
    void                gtk_action_group_set_translation_domain
                                                            (GtkActionGroup *action_group,
                                                             const gchar *domain);
    const gchar *       gtk_action_group_translate_string   (GtkActionGroup *action_group,
                                                             const gchar *string);

## Object Hierarchy

      GObject
       +----GtkActionGroup

## Implemented Interfaces

GtkActionGroup implements GtkBuildable.

## Properties

      "accel-group"              GtkAccelGroup*        : Read / Write
      "name"                     gchar*                : Read / Write / Construct Only
      "sensitive"                gboolean              : Read / Write
      "visible"                  gboolean              : Read / Write

## Signals

      "connect-proxy"
      "disconnect-proxy"
      "post-activate"
      "pre-activate"

## Description

Actions are organised into groups. An action group is essentially a map from names to GtkAction objects.

All actions that would make sense to use in a particular context should be in a single group. Multiple action groups may be used for a particular user interface. In fact, it is expected that most nontrivial applications will make use of multiple groups. For example, in an application that can edit multiple documents, one group holding global actions (e.g. quit, about, new), and one group per document holding actions that act on that document (eg. save, cut/copy/paste, etc). Each window's menus would be constructed from a combination of two action groups.

Accelerators are handled by the GTK+ accelerator map. All actions are assigned an accelerator path (which normally has the form `<Actions>/group-name/action-name`) and a shortcut is associated with this accelerator path. All menuitems and toolitems take on this accelerator path. The GTK+ accelerator map code makes sure that the correct shortcut is displayed next to the menu item.

### GtkActionGroup as GtkBuildable

The GtkActionGroup implementation of the GtkBuildable interface accepts GtkAction objects as <child> elements in UI definitions.

Note that it is probably more common to define actions and action groups in the code, since they are directly related to what the code can do.

The GtkActionGroup implementation of the GtkBuildable interface supports a custom <accelerator> element, which has attributes named key and modifiers and allows to specify accelerators. This is similar to the <accelerator> element of GtkWidget, the main difference is that it doesn't allow you to specify a signal.

Example 78. A GtkDialog UI definition fragment.

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    <object class="GtkActionGroup" id="actiongroup">
      <child>
          <object class="GtkAction" id="About">
              <property name="name">About</property>
              <property name="stock_id">gtk-about</property>
              <signal handler="about_activate" name="activate"/>
          </object>
          <accelerator key="F1" modifiers="GDK_CONTROL_MASK | GDK_SHIFT_MASK"/>
      </child>
    </object>

## Details

### struct GtkActionGroup

    struct GtkActionGroup;

### gtk_action_group_new ()

    GtkActionGroup *    gtk_action_group_new                (const gchar *name);

### Warning

`gtk_action_group_new` is deprecated and should not be used in newly-written code. 3.10

Creates a new GtkActionGroup object. The name of the action group is used when associating keybindings with the actions.

`name` : | the name of the action group.
Returns : | the new GtkActionGroup

Since 2.4

### gtk_action_group_get_name ()

    const gchar *       gtk_action_group_get_name           (GtkActionGroup *action_group);

### Warning

`gtk_action_group_get_name` is deprecated and should not be used in newly-written code. 3.10

Gets the name of the action group.

`action_group` : | the action group
Returns : | the name of the action group.

Since 2.4

### gtk_action_group_get_sensitive ()

    gboolean            gtk_action_group_get_sensitive      (GtkActionGroup *action_group);

### Warning

`gtk_action_group_get_sensitive` is deprecated and should not be used in newly-written code. 3.10

Returns `TRUE` if the group is sensitive. The constituent actions can only be logically sensitive (see `gtk_action_is_sensitive()`) if they are sensitive (see `gtk_action_get_sensitive()`) and their group is sensitive.

`action_group` : | the action group
Returns : | `TRUE` if the group is sensitive.

Since 2.4

### gtk_action_group_set_sensitive ()

    void                gtk_action_group_set_sensitive      (GtkActionGroup *action_group,
                                                             gboolean sensitive);

### Warning

`gtk_action_group_set_sensitive` is deprecated and should not be used in newly-written code. 3.10

Changes the sensitivity of `action_group`

`action_group` : | the action group
`sensitive` : | new sensitivity

Since 2.4

### gtk_action_group_get_visible ()

    gboolean            gtk_action_group_get_visible        (GtkActionGroup *action_group);

### Warning

`gtk_action_group_get_visible` is deprecated and should not be used in newly-written code. 3.10

Returns `TRUE` if the group is visible. The constituent actions can only be logically visible (see `gtk_action_is_visible()`) if they are visible (see `gtk_action_get_visible()`) and their group is visible.

`action_group` : | the action group
Returns : | `TRUE` if the group is visible.

Since 2.4

### gtk_action_group_set_visible ()

    void                gtk_action_group_set_visible        (GtkActionGroup *action_group,
                                                             gboolean visible);

### Warning

`gtk_action_group_set_visible` is deprecated and should not be used in newly-written code. 3.10

Changes the visible of `action_group`.

`action_group` : | the action group
`visible` : | new visiblity

Since 2.4

### gtk_action_group_get_accel_group ()

    GtkAccelGroup *     gtk_action_group_get_accel_group    (GtkActionGroup *action_group);

### Warning

`gtk_action_group_get_accel_group` is deprecated and should not be used in newly-written code. 3.10

Gets the accelerator group.

`action_group` : | a GtkActionGroup
Returns : | the accelerator group associated with this action group or `NULL` if there is none. [transfer none]

Since 3.6

### gtk_action_group_set_accel_group ()

    void                gtk_action_group_set_accel_group    (GtkActionGroup *action_group,
                                                             GtkAccelGroup *accel_group);

### Warning

`gtk_action_group_set_accel_group` is deprecated and should not be used in newly-written code. 3.10

Sets the accelerator group to be used by every action in this group.

`action_group` : | a GtkActionGroup
`accel_group` : | a GtkAccelGroup to set or `NULL`. [allow-none]

Since 3.6

### gtk_action_group_get_action ()

    GtkAction *         gtk_action_group_get_action         (GtkActionGroup *action_group,
                                                             const gchar *action_name);

### Warning

`gtk_action_group_get_action` is deprecated and should not be used in newly-written code. 3.10

Looks up an action in the action group by name.

`action_group` : | the action group
`action_name` : | the name of the action
Returns : | the action, or `NULL` if no action by that name exists. [transfer none]

Since 2.4

### gtk_action_group_list_actions ()

    GList *             gtk_action_group_list_actions       (GtkActionGroup *action_group);

### Warning

`gtk_action_group_list_actions` is deprecated and should not be used in newly-written code. 3.10

Lists the actions in the action group.

`action_group` : | the action group
Returns : | an allocated list of the action objects in the action group. [element-type GtkAction][transfer container]

Since 2.4

### gtk_action_group_add_action ()

    void                gtk_action_group_add_action         (GtkActionGroup *action_group,
                                                             GtkAction *action);

### Warning

`gtk_action_group_add_action` is deprecated and should not be used in newly-written code. 3.10

Adds an action object to the action group. Note that this function does not set up the accel path of the action, which can lead to problems if a user tries to modify the accelerator of a menuitem associated with the action. Therefore you must either set the accel path yourself with `gtk_action_set_accel_path()`, or use `gtk_action_group_add_action_with_accel (..., NULL)`.

`action_group` : | the action group
`action` : | an action

Since 2.4

### gtk_action_group_add_action_with_accel ()

    void                gtk_action_group_add_action_with_accel
                                                            (GtkActionGroup *action_group,
                                                             GtkAction *action,
                                                             const gchar *accelerator);

### Warning

`gtk_action_group_add_action_with_accel` is deprecated and should not be used in newly-written code. 3.10

Adds an action object to the action group and sets up the accelerator.

If `accelerator` is `NULL`, attempts to use the accelerator associated with the stock_id of the action.

Accel paths are set to `<Actions>/`group-name`/`action-name``.

`action_group` : | the action group
`action` : | the action to add
`accelerator` : | the accelerator for the action, in the format understood by `gtk_accelerator_parse()`, or "" for no accelerator, or `NULL` to use the stock accelerator. [allow-none]

Since 2.4

### gtk_action_group_remove_action ()

    void                gtk_action_group_remove_action      (GtkActionGroup *action_group,
                                                             GtkAction *action);

### Warning

`gtk_action_group_remove_action` is deprecated and should not be used in newly-written code. 3.10

Removes an action object from the action group.

`action_group` : | the action group
`action` : | an action

Since 2.4

### struct GtkActionEntry

    struct GtkActionEntry {
      const gchar     *name;
      const gchar     *stock_id;
      const gchar     *label;
      const gchar     *accelerator;
      const gchar     *tooltip;
      GCallback  callback;
    };

### Warning

`GtkActionEntry` is deprecated and should not be used in newly-written code. 3.10

GtkActionEntry structs are used with `gtk_action_group_add_actions()` to construct actions.

const gchar *`name`; | The name of the action.
const gchar *`stock_id`; | The stock id for the action, or the name of an icon from the icon theme.
const gchar *`label`; | The label for the action. This field should typically be marked for translation, see `gtk_action_group_set_translation_domain()`. If `label` is `NULL`, the label of the stock item with id `stock_id` is used.
const gchar *`accelerator`; | The accelerator for the action, in the format understood by `gtk_accelerator_parse()`.
const gchar *`tooltip`; | The tooltip for the action. This field should typically be marked for translation, see `gtk_action_group_set_translation_domain()`.
GCallback `callback`; | The function to call when the action is activated.

### gtk_action_group_add_actions ()

    void                gtk_action_group_add_actions        (GtkActionGroup *action_group,
                                                             const GtkActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data);

### Warning

`gtk_action_group_add_actions` is deprecated and should not be used in newly-written code. 3.10

This is a convenience function to create a number of actions and add them to the action group.

The "activate" signals of the actions are connected to the callbacks and their accel paths are set to `<Actions>/`group-name`/`action-name``.

`action_group` : | the action group
`entries` : | an array of action descriptions. [array length=n_entries]
`n_entries` : | the number of entries
`user_data` : | data to pass to the action callbacks

Since 2.4

### gtk_action_group_add_actions_full ()

    void                gtk_action_group_add_actions_full   (GtkActionGroup *action_group,
                                                             const GtkActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data,
                                                             GDestroyNotify destroy);

### Warning

`gtk_action_group_add_actions_full` is deprecated and should not be used in newly-written code. 3.10

This variant of `gtk_action_group_add_actions()` adds a GDestroyNotify callback for `user_data`.

`action_group` : | the action group
`entries` : | an array of action descriptions. [array length=n_entries]
`n_entries` : | the number of entries
`user_data` : | data to pass to the action callbacks
`destroy` : | destroy notification callback for `user_data`

Since 2.4

### struct GtkToggleActionEntry

    struct GtkToggleActionEntry {
      const gchar     *name;
      const gchar     *stock_id;
      const gchar     *label;
      const gchar     *accelerator;
      const gchar     *tooltip;
      GCallback  callback;
      gboolean   is_active;
    };

### Warning

`GtkToggleActionEntry` is deprecated and should not be used in newly-written code. 3.10

GtkToggleActionEntry structs are used with `gtk_action_group_add_toggle_actions()` to construct toggle actions.

const gchar *`name`; | The name of the action.
const gchar *`stock_id`; | The stock id for the action, or the name of an icon from the icon theme.
const gchar *`label`; | The label for the action. This field should typically be marked for translation, see `gtk_action_group_set_translation_domain()`.
const gchar *`accelerator`; | The accelerator for the action, in the format understood by `gtk_accelerator_parse()`.
const gchar *`tooltip`; | The tooltip for the action. This field should typically be marked for translation, see `gtk_action_group_set_translation_domain()`.
GCallback `callback`; | The function to call when the action is activated.
gboolean `is_active`; | The initial state of the toggle action.

### gtk_action_group_add_toggle_actions ()

    void                gtk_action_group_add_toggle_actions (GtkActionGroup *action_group,
                                                             const GtkToggleActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data);

### Warning

`gtk_action_group_add_toggle_actions` is deprecated and should not be used in newly-written code. 3.10

This is a convenience function to create a number of toggle actions and add them to the action group.

The "activate" signals of the actions are connected to the callbacks and their accel paths are set to `<Actions>/`group-name`/`action-name``.

`action_group` : | the action group
`entries` : | an array of toggle action descriptions. [array length=n_entries]
`n_entries` : | the number of entries
`user_data` : | data to pass to the action callbacks

Since 2.4

### gtk_action_group_add_toggle_actions_full ()

    void                gtk_action_group_add_toggle_actions_full
                                                            (GtkActionGroup *action_group,
                                                             const GtkToggleActionEntry *entries,
                                                             guint n_entries,
                                                             gpointer user_data,
                                                             GDestroyNotify destroy);

### Warning

`gtk_action_group_add_toggle_actions_full` is deprecated and should not be used in newly-written code. 3.10

This variant of `gtk_action_group_add_toggle_actions()` adds a GDestroyNotify callback for `user_data`.

`action_group` : | the action group
`entries` : | an array of toggle action descriptions. [array length=n_entries]
`n_entries` : | the number of entries
`user_data` : | data to pass to the action callbacks
`destroy` : | destroy notification callback for `user_data`

Since 2.4

### struct GtkRadioActionEntry

    struct GtkRadioActionEntry {
      const gchar *name;
      const gchar *stock_id;
      const gchar *label;
      const gchar *accelerator;
      const gchar *tooltip;
      gint   value;
    };

### Warning

`GtkRadioActionEntry` is deprecated and should not be used in newly-written code. 3.10

GtkRadioActionEntry structs are used with `gtk_action_group_add_radio_actions()` to construct groups of radio actions.

const gchar *`name`; | The name of the action.
const gchar *`stock_id`; | The stock id for the action, or the name of an icon from the icon theme.
const gchar *`label`; | The label for the action. This field should typically be marked for translation, see `gtk_action_group_set_translation_domain()`.
const gchar *`accelerator`; | The accelerator for the action, in the format understood by `gtk_accelerator_parse()`.
const gchar *`tooltip`; | The tooltip for the action. This field should typically be marked for translation, see `gtk_action_group_set_translation_domain()`.
gint `value`; | The value to set on the radio action. See `gtk_radio_action_get_current_value()`.

### gtk_action_group_add_radio_actions ()

    void                gtk_action_group_add_radio_actions  (GtkActionGroup *action_group,
                                                             const GtkRadioActionEntry *entries,
                                                             guint n_entries,
                                                             gint value,
                                                             GCallback on_change,
                                                             gpointer user_data);

### Warning

`gtk_action_group_add_radio_actions` is deprecated and should not be used in newly-written code. 3.10

This is a convenience routine to create a group of radio actions and add them to the action group.

The "changed" signal of the first radio action is connected to the `on_change` callback and the accel paths of the actions are set to `<Actions>/`group-name`/`action-name``.

`action_group` : | the action group
`entries` : | an array of radio action descriptions. [array length=n_entries]
`n_entries` : | the number of entries
`value` : | the value of the action to activate initially, or -1 if no action should be activated
`on_change` : | the callback to connect to the changed signal
`user_data` : | data to pass to the action callbacks

Since 2.4

### gtk_action_group_add_radio_actions_full ()

    void                gtk_action_group_add_radio_actions_full
                                                            (GtkActionGroup *action_group,
                                                             const GtkRadioActionEntry *entries,
                                                             guint n_entries,
                                                             gint value,
                                                             GCallback on_change,
                                                             gpointer user_data,
                                                             GDestroyNotify destroy);

### Warning

`gtk_action_group_add_radio_actions_full` is deprecated and should not be used in newly-written code. 3.10

This variant of `gtk_action_group_add_radio_actions()` adds a GDestroyNotify callback for `user_data`.

`action_group` : | the action group
`entries` : | an array of radio action descriptions. [array length=n_entries]
`n_entries` : | the number of entries
`value` : | the value of the action to activate initially, or -1 if no action should be activated
`on_change` : | the callback to connect to the changed signal
`user_data` : | data to pass to the action callbacks
`destroy` : | destroy notification callback for `user_data`

Since 2.4

### GtkTranslateFunc ()

    gchar *             (*GtkTranslateFunc)                 (const gchar *path,
                                                             gpointer func_data);

### gtk_action_group_set_translate_func ()

    void                gtk_action_group_set_translate_func (GtkActionGroup *action_group,
                                                             GtkTranslateFunc func,
                                                             gpointer data,
                                                             GDestroyNotify notify);

### Warning

`gtk_action_group_set_translate_func` is deprecated and should not be used in newly-written code. 3.10

Sets a function to be used for translating the `label` and `tooltip` of GtkActionEntrys added by `gtk_action_group_add_actions()`.

If you're using `gettext()`, it is enough to set the translation domain with `gtk_action_group_set_translation_domain()`.

`action_group` : | a GtkActionGroup
`func` : | a GtkTranslateFunc
`data` : | data to be passed to `func` and `notify`
`notify` : | a GDestroyNotify function to be called when `action_group` is destroyed and when the translation function is changed again

Since 2.4

### gtk_action_group_set_translation_domain ()

    void                gtk_action_group_set_translation_domain
                                                            (GtkActionGroup *action_group,
                                                             const gchar *domain);

### Warning

`gtk_action_group_set_translation_domain` is deprecated and should not be used in newly-written code. 3.10

Sets the translation domain and uses `g_dgettext()` for translating the `label` and `tooltip` of GtkActionEntrys added by `gtk_action_group_add_actions()`.

If you're not using `gettext()` for localization, see `gtk_action_group_set_translate_func()`.

`action_group` : | a GtkActionGroup
`domain` : | the translation domain to use for `g_dgettext()` calls, or `NULL` to use the domain set with `textdomain()`. [allow-none]

Since 2.4

### gtk_action_group_translate_string ()

    const gchar *       gtk_action_group_translate_string   (GtkActionGroup *action_group,
                                                             const gchar *string);

### Warning

`gtk_action_group_translate_string` is deprecated and should not be used in newly-written code. 3.10

Translates a string using the function set with `gtk_action_group_set_translate_func()`. This is mainly intended for language bindings.

`action_group` : | a GtkActionGroup
`string` : | a string
Returns : | the translation of `string`

Since 2.6

## Property Details

### The `"accel-group"` property

      "accel-group"              GtkAccelGroup*        : Read / Write

### Warning

`GtkActionGroup:accel-group` is deprecated and should not be used in newly-written code. 3.10

The accelerator group the actions of this group should use.

### The `"name"` property

      "name"                     gchar*                : Read / Write / Construct Only

### Warning

`GtkActionGroup:name` is deprecated and should not be used in newly-written code. 3.10

A name for the action.

Default value: NULL

### The `"sensitive"` property

      "sensitive"                gboolean              : Read / Write

### Warning

`GtkActionGroup:sensitive` is deprecated and should not be used in newly-written code. 3.10

Whether the action group is enabled.

Default value: TRUE

### The `"visible"` property

      "visible"                  gboolean              : Read / Write

### Warning

`GtkActionGroup:visible` is deprecated and should not be used in newly-written code. 3.10

Whether the action group is visible.

Default value: TRUE

## Signal Details

### The `"connect-proxy"` signal

    void                user_function                      (GtkActionGroup *action_group,
                                                            GtkAction      *action,
                                                            GtkWidget      *proxy,
                                                            gpointer        user_data)

### Warning

`GtkActionGroup::connect-proxy` is deprecated and should not be used in newly-written code. 3.10

The ::connect-proxy signal is emitted after connecting a proxy to an action in the group. Note that the proxy may have been connected to a different action before.

This is intended for simple customizations for which a custom action class would be too clumsy, e.g. showing tooltips for menuitems in the statusbar.

GtkUIManager proxies the signal and provides global notification just before any action is connected to a proxy, which is probably more convenient to use.

`action_group` : | the group
`action` : | the action
`proxy` : | the proxy
`user_data` : | user data set when the signal handler was connected.

Since 2.4

### The `"disconnect-proxy"` signal

    void                user_function                      (GtkActionGroup *action_group,
                                                            GtkAction      *action,
                                                            GtkWidget      *proxy,
                                                            gpointer        user_data)

### Warning

`GtkActionGroup::disconnect-proxy` is deprecated and should not be used in newly-written code. 3.10

The ::disconnect-proxy signal is emitted after disconnecting a proxy from an action in the group.

GtkUIManager proxies the signal and provides global notification just before any action is connected to a proxy, which is probably more convenient to use.

`action_group` : | the group
`action` : | the action
`proxy` : | the proxy
`user_data` : | user data set when the signal handler was connected.

Since 2.4

### The `"post-activate"` signal

    void                user_function                      (GtkActionGroup *action_group,
                                                            GtkAction      *action,
                                                            gpointer        user_data)

### Warning

`GtkActionGroup::post-activate` is deprecated and should not be used in newly-written code. 3.10

The ::post-activate signal is emitted just after the `action` in the `action_group` is activated

This is intended for GtkUIManager to proxy the signal and provide global notification just after any action is activated.

`action_group` : | the group
`action` : | the action
`user_data` : | user data set when the signal handler was connected.

Since 2.4

### The `"pre-activate"` signal

    void                user_function                      (GtkActionGroup *action_group,
                                                            GtkAction      *action,
                                                            gpointer        user_data)

### Warning

`GtkActionGroup::pre-activate` is deprecated and should not be used in newly-written code. 3.10

The ::pre-activate signal is emitted just before the `action` in the `action_group` is activated

This is intended for GtkUIManager to proxy the signal and provide global notification just before any action is activated.

`action_group` : | the group
`action` : | the action
`user_data` : | user data set when the signal handler was connected.

Since 2.4