Automatic resources

GtkApplication will automatically load menus from the GtkBuilder file located at "gtk/menus.ui", relative to the application's resource base path (see g_application_set_resource_base_path()). The menu with the ID "app-menu" is taken as the application's app menu and the menu with the ID "menubar" is taken as the application's menubar. Additional menus (most interesting submenus) can be named and accessed via gtk_application_get_menu_by_id() which allows for dynamic population of a part of the menu structure.

If the files "gtk/menus-appmenu.ui" or "gtk/menus-traditional.ui" are present then these files will be used in preference, depending on the value of gtk_application_prefers_app_menu().

It is also possible to provide the menus manually using gtk_application_set_app_menu() and gtk_application_set_menubar().

GtkApplication will also automatically setup an icon search path for the default icon theme by appending "icons" to the resource base path. This allows your application to easily store its icons as resources. See gtk_icon_theme_add_resource_path() for more information.

A simple application

A simple example

GtkApplication optionally registers with a session manager of the users session (if you set the “register-session” property) and offers various functionality related to the session life-cycle.

An application can block various ways to end the session with the gtk_application_inhibit() function. Typical use cases for this kind of inhibiting are long-running, uninterruptible operations, such as burning a CD or performing a disk backup. The session manager may not honor the inhibitor, but it can be expected to inform the user about the negative consequences of ending the session while inhibitors are present.

gtk_application_new ()

GtkApplication *
gtk_application_new (const gchar *application_id,
                     GApplicationFlags flags);

Creates a new GtkApplication instance.

When using GtkApplication, it is not necessary to call gtk_init() manually. It is called as soon as the application gets registered as the primary instance.

Concretely, gtk_init() is called in the default handler for the “startup” signal. Therefore, GtkApplication subclasses should chain up in their “startup” handler before using any GTK+ API.

Note that commandline arguments are not passed to gtk_init(). All GTK+ functionality that is available via commandline arguments can also be achieved by setting suitable environment variables such as G_DEBUG, so this should not be a big problem. If you absolutely must support GTK+ commandline arguments, you can explicitly call gtk_init() before creating the application instance.

If non-NULL, the application ID must be valid. See g_application_id_is_valid().

If no application ID is given then some features (most notably application uniqueness) will be disabled. A null application ID is only allowed with GTK+ 3.6 or later.

Since 3.0

gtk_application_add_window ()

void
gtk_application_add_window (GtkApplication *application,
                            GtkWindow *window);

Adds a window to application .

This call is equivalent to setting the “application” property of window to application .

Normally, the connection between the application and the window will remain until the window is destroyed, but you can explicitly remove it with gtk_application_remove_window().

GTK+ will keep the application running as long as it has any windows.

Since 3.0

gtk_application_remove_window ()

void
gtk_application_remove_window (GtkApplication *application,
                               GtkWindow *window);

Remove a window from application .

If window belongs to application then this call is equivalent to setting the “application” property of window to NULL.

The application may stop running as a result of a call to this function.

Since 3.0

gtk_application_get_windows ()

GList *
gtk_application_get_windows (GtkApplication *application);

Gets a list of the GtkWindows associated with application .

The list is sorted by most recently focused window, such that the first element is the currently focused window. (Useful for choosing a parent for a transient window.)

The list that is returned should not be modified in any way. It will only remain valid until the next focus change or window creation or deletion.

Since 3.0

gtk_application_get_window_by_id ()

GtkWindow *
gtk_application_get_window_by_id (GtkApplication *application,
                                  guint id);

Returns the GtkApplicationWindow with the given ID.

Since 3.6

gtk_application_get_active_window ()

GtkWindow *
gtk_application_get_active_window (GtkApplication *application);

Gets the “active” window for the application.

The active window is the one that was most recently focused (within the application). This window may not have the focus at the moment if another application has it -- this is just the most recently-focused window within this application.

Since 3.6

gtk_application_inhibit ()

guint
gtk_application_inhibit (GtkApplication *application,
                         GtkWindow *window,
                         GtkApplicationInhibitFlags flags,
                         const gchar *reason);

Inform the session manager that certain types of actions should be inhibited. This is not guaranteed to work on all platforms and for all types of actions.

Applications should invoke this method when they begin an operation that should not be interrupted, such as creating a CD or DVD. The types of actions that may be blocked are specified by the flags parameter. When the application completes the operation it should call gtk_application_uninhibit() to remove the inhibitor. Note that an application can have multiple inhibitors, and all of the must be individually removed. Inhibitors are also cleared when the application exits.

Applications should not expect that they will always be able to block the action. In most cases, users will be given the option to force the action to take place.

Reasons should be short and to the point.

If window is given, the session manager may point the user to this window to find out more about why the action is inhibited.

Since 3.4

gtk_application_uninhibit ()

void
gtk_application_uninhibit (GtkApplication *application,
                           guint cookie);

Removes an inhibitor that has been established with gtk_application_inhibit(). Inhibitors are also cleared when the application exits.

Since 3.4

gtk_application_is_inhibited ()

gboolean
gtk_application_is_inhibited (GtkApplication *application,
                              GtkApplicationInhibitFlags flags);

Determines if any of the actions specified in flags are currently inhibited (possibly by another application).

Since 3.4

gtk_application_prefers_app_menu ()

gboolean
gtk_application_prefers_app_menu (GtkApplication *application);

Determines if the desktop environment in which the application is running would prefer an application menu be shown.

If this function returns TRUE then the application should call gtk_application_set_app_menu() with the contents of an application menu, which will be shown by the desktop environment. If it returns FALSE then you should consider using an alternate approach, such as a menubar.

The value returned by this function is purely advisory and you are free to ignore it. If you call gtk_application_set_app_menu() even if the desktop environment doesn't support app menus, then a fallback will be provided.

Applications are similarly free not to set an app menu even if the desktop environment wants to show one. In that case, a fallback will also be created by the desktop environment (GNOME, for example, uses a menu with only a "Quit" item in it).

The value returned by this function never changes. Once it returns a particular value, it is guaranteed to always return the same value.

You may only call this function after the application has been registered and after the base startup handler has run. You're most likely to want to use this from your own startup handler. It may also make sense to consult this function while constructing UI (in activate, open or an action activation handler) in order to determine if you should show a gear menu or not.

This function will return FALSE on Mac OS and a default app menu will be created automatically with the "usual" contents of that menu typical to most Mac OS applications. If you call gtk_application_set_app_menu() anyway, then this menu will be replaced with your own.

Since 3.14

gtk_application_get_app_menu ()

GMenuModel *
gtk_application_get_app_menu (GtkApplication *application);

Returns the menu model that has been set with gtk_application_set_app_menu().

Since 3.4

gtk_application_set_app_menu ()

void
gtk_application_set_app_menu (GtkApplication *application,
                              GMenuModel *app_menu);

Sets or unsets the application menu for application .

This can only be done in the primary instance of the application, after it has been registered. “startup” is a good place to call this.

The application menu is a single menu containing items that typically impact the application as a whole, rather than acting on a specific window or document. For example, you would expect to see “Preferences” or “Quit” in an application menu, but not “Save” or “Print”.

If supported, the application menu will be rendered by the desktop environment.

Use the base GActionMap interface to add actions, to respond to the user selecting these menu items.

Since 3.4

gtk_application_get_menubar ()

GMenuModel *
gtk_application_get_menubar (GtkApplication *application);

Returns the menu model that has been set with gtk_application_set_menubar().

Since 3.4

gtk_application_set_menubar ()

void
gtk_application_set_menubar (GtkApplication *application,
                             GMenuModel *menubar);

Sets or unsets the menubar for windows of application .

This is a menubar in the traditional sense.

This can only be done in the primary instance of the application, after it has been registered. “startup” is a good place to call this.

Depending on the desktop environment, this may appear at the top of each window, or at the top of the screen. In some environments, if both the application menu and the menubar are set, the application menu will be presented as if it were the first item of the menubar. Other environments treat the two as completely separate -- for example, the application menu may be rendered by the desktop shell while the menubar (if set) remains in each individual window.

Use the base GActionMap interface to add actions, to respond to the user selecting these menu items.

Since 3.4

gtk_application_get_menu_by_id ()

GMenu *
gtk_application_get_menu_by_id (GtkApplication *application,
                                const gchar *id);

Gets a menu from automatically loaded resources. See Automatic resources for more information.

Since 3.14

gtk_application_add_accelerator ()

void
gtk_application_add_accelerator (GtkApplication *application,
                                 const gchar *accelerator,
                                 const gchar *action_name,
                                 GVariant *parameter);

Installs an accelerator that will cause the named action to be activated when the key combination specificed by accelerator is pressed.

accelerator must be a string that can be parsed by gtk_accelerator_parse(), e.g. "<Primary>q" or “<Control><Alt>p”.

action_name must be the name of an action as it would be used in the app menu, i.e. actions that have been added to the application are referred to with an “app.” prefix, and window-specific actions with a “win.” prefix.

GtkApplication also extracts accelerators out of “accel” attributes in the GMenuModels passed to gtk_application_set_app_menu() and gtk_application_set_menubar(), which is usually more convenient than calling this function for each accelerator.

Since 3.4

gtk_application_remove_accelerator ()

void
gtk_application_remove_accelerator (GtkApplication *application,
                                    const gchar *action_name,
                                    GVariant *parameter);

Removes an accelerator that has been previously added with gtk_application_add_accelerator().

Since 3.4

gtk_application_list_action_descriptions ()

gchar **
gtk_application_list_action_descriptions
                               (GtkApplication *application);

Lists the detailed action names which have associated accelerators. See gtk_application_set_accels_for_action().

Since 3.12

gtk_application_get_accels_for_action ()

gchar **
gtk_application_get_accels_for_action (GtkApplication *application,
                                       const gchar *detailed_action_name);

Gets the accelerators that are currently associated with the given action.

Since 3.12

gtk_application_set_accels_for_action ()

void
gtk_application_set_accels_for_action (GtkApplication *application,
                                       const gchar *detailed_action_name,
                                       const gchar * const *accels);

Sets zero or more keyboard accelerators that will trigger the given action. The first item in accels will be the primary accelerator, which may be displayed in the UI.

To remove all accelerators for an action, use an empty, zero-terminated array for accels .

Since 3.12

gtk_application_get_actions_for_accel ()

gchar **
gtk_application_get_actions_for_accel (GtkApplication *application,
                                       const gchar *accel);

Returns the list of actions (possibly empty) that accel maps to. Each item in the list is a detailed action name in the usual form.

This might be useful to discover if an accel already exists in order to prevent installation of a conflicting accelerator (from an accelerator editor or a plugin system, for example). Note that having more than one action per accelerator may not be a bad thing and might make sense in cases where the actions never appear in the same context.

In case there are no actions for a given accelerator, an empty array is returned. NULL is never returned.

It is a programmer error to pass an invalid accelerator string. If you are unsure, check it with gtk_accelerator_parse() first.

Since 3.14

struct GtkApplication

struct GtkApplication;

struct GtkApplicationClass

struct GtkApplicationClass {
  GApplicationClass parent_class;


  void (*window_added)   (GtkApplication *application,
                          GtkWindow      *window);
  void (*window_removed) (GtkApplication *application,
                          GtkWindow      *window);
};

enum GtkApplicationInhibitFlags

Types of user actions that may be blocked by gtk_application_inhibit().

Since 3.4

The “active-window” property

  “active-window”            GtkWindow *

The window which most recently had focus.

Flags: Read

The “app-menu” property

  “app-menu”                 GMenuModel *

The GMenuModel for the application menu.

Flags: Read / Write

The “menubar” property

  “menubar”                  GMenuModel *

The GMenuModel for the menubar.

Flags: Read / Write

The “register-session” property

  “register-session”         gboolean

Set this property to TRUE to register with the session manager.

Flags: Read / Write

Default value: FALSE

Since 3.4

The “window-added” signal

void
user_function (GtkApplication *application,
               GtkWindow      *window,
               gpointer        user_data)

Emitted when a GtkWindow is added to application through gtk_application_add_window().

Flags: Run First

Since 3.2

The “window-removed” signal

void
user_function (GtkApplication *application,
               GtkWindow      *window,
               gpointer        user_data)

Emitted when a GtkWindow is removed from application , either as a side-effect of being destroyed or explicitly through gtk_application_remove_window().

Flags: Run First

Since 3.2