Application

class Application(**properties: Any)

Superclasses: Application, Object

Implemented Interfaces: ActionGroup, ActionMap

GtkApplication is a high-level API for writing applications.

It supports many aspects of writing a GTK application in a convenient fashion, without enforcing a one-size-fits-all model.

Currently, GtkApplication handles GTK initialization, application uniqueness, session management, provides some basic scriptability and desktop shell integration by exporting actions and menus and manages a list of toplevel windows whose life-cycle is automatically tied to the life-cycle of your application.

While GtkApplication works fine with plain Window’s, it is recommended to use it together with ApplicationWindow.

Automatic resources

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

Note that automatic resource loading uses the resource base path that is set at construction time and will not work if the resource base path is changed at a later time.

It is also possible to provide the menubar manually using 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 add_resource_path for more information.

If there is a resource located at gtk/help-overlay.ui which defines a ShortcutsWindow with ID help_overlay then GtkApplication associates an instance of this shortcuts window with each ApplicationWindow and sets up the keyboard accelerator Control`+<kbd>?</kbd> to open it. To create a menu item that displays the shortcuts window, associate the item with the action ``win.show-help-overlay`.

A simple application

A simple example is available in the GTK source code repository

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 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.

See Also

HowDoI: Using GtkApplication, Getting Started with GTK: Basics

Constructors

class Application

classmethod new(application_id: str | None, flags: ApplicationFlags) → Application

Creates a new GtkApplication instance.

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

Concretely, init is called in the default handler for the GApplication::startup signal. Therefore, GtkApplication subclasses should always chain up in their GApplication::startup handler before using any GTK API.

Note that commandline arguments are not passed to init.

If application_id is not None, then it must be valid. See :func:`~gi.repository.Gio.Gio.Application.id_is_valid`.

If no application ID is given then some features (most notably application uniqueness) will be disabled.

Parameters:

• application_id – The application ID

• flags – the application flags

Methods

class Application

add_window(window: Window) → None

Adds a window to application.

This call can only happen after the application has started; typically, you should add new application windows in response to the emission of the GApplication::activate signal.

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 remove_window.

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

Parameters:

window – a GtkWindow

get_accels_for_action(detailed_action_name: str) → list[str]

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

Parameters:

detailed_action_name – a detailed action name, specifying an action and target to obtain accelerators for

get_actions_for_accel(accel: str) → list[str]

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 accelerator_parse first.

Parameters:

accel – an accelerator that can be parsed by accelerator_parse

get_active_window() → Window | None

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.

get_menu_by_id(id: str) → Menu | None

Gets a menu from automatically loaded resources.

See the section on Automatic resources for more information.

Parameters:

id – the id of the menu to look up

get_menubar() → MenuModel | None

Returns the menu model that has been set with set_menubar.

get_window_by_id(id: int) → Window | None

Returns the ApplicationWindow with the given ID.

The ID of a GtkApplicationWindow can be retrieved with get_id.

Parameters:

id – an identifier number

get_windows() → list[Window]

Gets a list of the Window instances 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.

inhibit(window: Window | None, flags: ApplicationInhibitFlags, reason: str | None = None) → int

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 uninhibit to remove the inhibitor. Note that an application can have multiple inhibitors, and all of them 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.

The reason message 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.

Parameters:

• window – a GtkWindow

• flags – what types of actions should be inhibited

• reason – a short, human-readable string that explains why these operations are inhibited

list_action_descriptions() → list[str]

Lists the detailed action names which have associated accelerators.

See set_accels_for_action.

remove_window(window: Window) → None

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, if window was the last window of the application.

Parameters:

window – a GtkWindow

set_accels_for_action(detailed_action_name: str, accels: Sequence[str]) → None

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.

For the detailed_action_name, see :func:`~gi.repository.Gio.Action.parse_detailed_name` and :func:`~gi.repository.Gio.Action.print_detailed_name`.

Parameters:

• detailed_action_name – a detailed action name, specifying an action and target to associate accelerators with

• accels – a list of accelerators in the format understood by accelerator_parse

set_menubar(menubar: MenuModel | None = None) → None

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. GApplication::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.

Parameters:

menubar – a GMenuModel

uninhibit(cookie: int) → None

Removes an inhibitor that has been previously established.

See inhibit.

Inhibitors are also cleared when the application exits.

Parameters:

cookie – a cookie that was returned by inhibit

Properties

class Application

props.active_window: Window

The currently focused window of the application.

props.menubar: MenuModel

The GMenuModel to be used for the application’s menu bar.

props.register_session: bool

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

This will make GTK track the session state (such as the screensaver_active property).

props.screensaver_active: bool

This property is TRUE if GTK believes that the screensaver is currently active.

GTK only tracks session state (including this) when register_session is set to True.

Tracking the screensaver state is currently only supported on Linux.

Signals

class Application.signals

query_end() → None

Emitted when the session manager is about to end the session.

This signal is only emitted if register_session is TRUE. Applications can connect to this signal and call inhibit with GTK_APPLICATION_INHIBIT_LOGOUT to delay the end of the session until state has been saved.

window_added(window: Window) → None

Emitted when a Window is added to application through add_window.

Parameters:

window – the newly-added Window

window_removed(window: Window) → None

Emitted when a Window is removed from application.

This can happen as a side-effect of the window being destroyed or explicitly through remove_window.

Parameters:

window – the Window that is being removed

Virtual Methods

class Application

do_window_added(window: Window) → None

Signal emitted when a GtkWindow is added to application through add_window().

Parameters:

window

do_window_removed(window: Window) → None

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

Parameters:

window

Fields

class Application

parent_instance