Gnome::Gtk3::Application

Table of Contents
Description
Automatic resources
See Also
Synopsis
Declaration
Uml Diagram

Inheriting this class
Types
GtkApplicationInhibitFlags
Methods
new
:app-id, :flags
:native-object
:build-id
add-window
get-accels-for-action
get-actions-for-accel
get-active-window
get-app-menu
get-menu-by-id
get-menubar
get-window-by-id
get-windows
inhibit
is-inhibited
list-action-descriptions
prefers-app-menu
remove-window
set-accels-for-action
set-app-menu
set-menubar
uninhibit
_gtk_application_new
Signals
query-end
window-added
window-removed
Properties
active-window
app-menu
menubar
register-session
screensaver-active
Signals
First method
Second method
Supported signals
query-end
window-added
window-removed
Properties
Supported properties
Active window: active-window
Application menu: app-menu
Menubar: menubar
Register session: register-session
Screensaver Active: screensaver-active

Application class

Description

Gnome::Gtk3::Application is a class that handles many important aspects of a GTK+ application in a convenient fashion, without enforcing a one-size-fits-all application model.

Currently, Gnome::Gtk3::Application 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 Gnome::Gtk3::Application works fine with plain Gnome::Gtk3::Windows, it is recommended to use it together with Gnome::Gtk3::ApplicationWindow.

When GDK threads are enabled, Gnome::Gtk3::Application will acquire the GDK lock when invoking actions that arrive from other processes. The GDK lock is not touched for local action invocations. In order to have actions invoked in a predictable context it is therefore recommended that the GDK lock be held while invoking actions locally with g_action_group_activate_action(). The same applies to actions associated with Gnome::Gtk3::ApplicationWindow and to the “activate” and “open” GApplication methods.

Automatic resources

Gnome::Gtk3::Application will automatically load menus from the Gnome::Gtk3::Builder resource 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 get_menu_by_id() which allows for dynamic population of a part of the menu structure.

If the resources "gtk/menus-appmenu.ui" or "gtk/menus-traditional.ui" are present then these files will be used in preference, depending on the value of prefers_app_menu(). If the resource "gtk/menus-common.ui" is present it will be loaded as well. This is useful for storing items that are referenced from both "gtk/menus-appmenu.ui" and "gtk/menus-traditional.ui".

It is also possible to provide the menus manually using set_app_menu() and set_menubar().

If there is a resource located at "gtk/help-overlay.ui" which defines a Gnome::Gtk3::ShortcutsWindow with ID "help_overlay" then Gnome::Gtk3::Application associates an instance of this shortcuts window with each Gnome::Gtk3::ApplicationWindow and sets up keyboard accelerators (Control-F1 and Control-?) to open it. To create a menu item that displays the shortcuts window, associate the item with the action win.show-help-overlay.

Synopsis

Declaration

unit class Gnome::Gtk3::Application;
also is Gnome::Gio::Application;

Uml Diagram

Inheriting this class

Inheriting is done in a special way in that it needs a call from new() to get the native object created by the class you are inheriting from.

use Gnome::Gtk3::Application:api<1>;

unit class MyGuiClass;
also is Gnome::Gtk3::Application;

submethod new ( |c ) {
  # let the Gnome::Gtk3::Application class process the options
  self.bless( :GtkApplication, |c);
}

submethod BUILD ( ... ) {
  ...
}

Types

GtkApplicationInhibitFlags

GTK_APPLICATION_INHIBIT_LOGOUT; Inhibit ending the user session by logging out or by shutting down the computer
GTK_APPLICATION_INHIBIT_SWITCH; Inhibit user switching
GTK_APPLICATION_INHIBIT_SUSPEND; Inhibit suspending the session or computer
GTK_APPLICATION_INHIBIT_IDLE; Inhibit the session being marked as idle (and possibly locked)

Methods

new

:app-id, :flags

Create a new Application object.

If the application ID is defined, it must be valid. See also id-is-valid() in Gnome::Gio::Application.

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

multi method new (
  Str :$app-id!,
  GApplicationFlags :$flags = G_APPLICATION_FLAGS_NONE
)

:native-object

Create an object using a native object from elsewhere. See also Gnome::N::TopLevelSupportClass.

multi method new ( N-GObject :$native-object! )

:build-id

Create an object using a native object from a builder. See also Gnome::GObject::Object.

multi method new ( Str :$build-id! )

add-window

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 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.

method add-window ( N-GObject() $window )

$window; a Gnome::Gtk3::Window

get-accels-for-action

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

Returns: accelerators for detailed-action-name, as a undefined-terminated array. Free with g-strfreev() when no longer needed

method get-accels-for-action ( Str $detailed_action_name --> Array )

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

get-actions-for-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. undefined 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.

Returns: a undefined-terminated array of actions for accel

method get-actions-for-accel ( Str $accel --> Array )

$accel; an accelerator that can be parsed by gtk-accelerator-parse()

get-active-window

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.

Returns: the active window, or undefined if there isn't one.

method get-active-window ( --> N-GObject )

$child-type: This is an optional argument. You can specify a real type or a type as a string. In the latter case the type must be defined in a module which can be found by the Raku require call.

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

Returns: the application menu of application or undefined if no application menu has been set.

method get-app-menu ( --> N-GObject )

$child-type: This is an optional argument. You can specify a real type or a type as a string. In the latter case the type must be defined in a module which can be found by the Raku require call.

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

method get-menu-by-id ( Str $id --> N-GObject )

$id; the id of the menu to look up

get-menubar

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

Returns: the menubar for windows of application

method get-menubar ( --> N-GObject )

get-window-by-id

Returns the Gnome::Gtk3::ApplicationWindow with the given ID.

The ID of a Gnome::Gtk3::ApplicationWindow can be retrieved with window-get-id().

Returns: the window with ID id, or undefined if there is no window with this ID

method get-window-by-id ( UInt $id --> N-GObject )

$id; an identifier number

get-windows

Gets a list of the Gnome::Gtk3::Windows 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.

Returns: (element-type GtkWindow) : a Gnome::Gtk3::List of Gnome::Gtk3::Window

method get-windows ( --> N-GList )

inhibit

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.

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.

Returns: A non-zero cookie that is used to uniquely identify this request. It should be used as an argument to uninhibit() in order to remove the request. If the platform does not support inhibiting or the request failed for some reason, 0 is returned.

method inhibit ( N-GObject() $window, Int $flags, Str $reason --> UInt )

$window; a Gnome::Gtk3::Window, or undefined
$flags; GtkApplicationInhibitFlags mask of what types of actions should be inhibited
$reason; a short, human-readable string that explains why these operations are inhibited

is-inhibited

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

Note that this information may not be available (for example when the application is running in a sandbox).

Returns: True if any of the actions specified in $flags are inhibited

method is-inhibited ( Int $flags --> Bool )

$flags; GtkApplicationInhibitFlags mask of what types of actions should be queried

list-action-descriptions

Lists the detailed action names which have associated accelerators. See set-accels-for-action().

Returns: an array of strings

method list-action-descriptions ( --> Array )

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 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 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.

Returns: True if you should set an app menu

method prefers-app-menu ( --> Bool )

remove-window

Remove a window from application.

If window belongs to application then this call is equivalent to setting the application property of window to undefined.

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

method remove-window ( N-GObject() $window )

$window; a Gnome::Gtk3::Window

set-accels-for-action

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 array $accels.

For the $detailed-action-name, see Gnome::Gio::Action.parse-detailed-name() and Gnome::Gio::Action.print-detailed-name().

method set-accels-for-action (
  Str $detailed_action_name, Array $accels
)

$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 gtk-accelerator-parse()

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 Gnome::Gtk3::ActionMap interface to add actions, to respond to the user selecting these menu items.

method set-app-menu ( N-GObject() $app_menu )

$app_menu; a Gnome::Gtk3::MenuModel, or undefined

set-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 Gnome::Gtk3::ActionMap interface to add actions, to respond to the user selecting these menu items.

method set-menubar ( N-GObject() $menubar )

$menubar; a Gnome::Gtk3::MenuModel, or undefined

uninhibit

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

method uninhibit ( UInt $cookie )

$cookie; a cookie that was returned by inhibit()

_gtk_application_new

Creates a new Gnome::Gtk3::Application instance.

When using Gnome::Gtk3::Application, 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, Gnome::Gtk3::Application 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-undefined, 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.

Returns: a new Gnome::Gtk3::Application instance

method _gtk_application_new (
  Str $application_id, GApplicationFlags $flags --> N-GObject
)

$application_id; The application ID.
GApplicationFlags $flags; the application flags

Signals

query-end

Emitted when the session manager is about to end the session, only 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..8

method handler (
  Gnome::Gtk3::Application :_widget($application),
  Int :$_handler-id,
  N-GObject :$_native-object,
  *%user-options
)

$application; The instance which registered the signal
$_handler-id; The handler id which is returned from the registration
$_native-object; The native object provided by the caller wrapped in the Raku object.
%user-options; A list of named arguments provided at the register-signal() method

window-added

Emitted when a Gnome::Gtk3::Window is added to application through add_window().

method handler (
  Unknown type: GTK_TYPE_WINDOW $window,
  Gnome::Gtk3::Application :_widget($application),
  Int :$_handler-id,
  N-GObject :$_native-object,
  *%user-options
)

$window; the newly-added Gnome::Gtk3::Window
$application; The instance which registered the signal
$_handler-id; The handler id which is returned from the registration
$_native-object; The native object provided by the caller wrapped in the Raku object.
%user-options; A list of named arguments provided at the register-signal() method

window-removed

Emitted when a Gnome::Gtk3::Window is removed from application, either as a side-effect of being destroyed or explicitly through remove_window().

method handler (
  Unknown type: GTK_TYPE_WINDOW $window,
  Gnome::Gtk3::Application :_widget($application),
  Int :$_handler-id,
  N-GObject :$_native-object,
  *%user-options
)

$window; the Gnome::Gtk3::Window that is being removed
$application; The instance which registered the signal
$_handler-id; The handler id which is returned from the registration
$_native-object; The native object provided by the caller wrapped in the Raku object.
%user-options; A list of named arguments provided at the register-signal() method

Properties

active-window

The window which most recently had focus

The Gnome::GObject::Value type of property active-window is G_TYPE_OBJECT.

Parameter is readable.

The GMenuModel for the application menu

The Gnome::GObject::Value type of property app-menu is G_TYPE_OBJECT.

Parameter is readable and writable.

menubar

The GMenuModel for the menubar

The Gnome::GObject::Value type of property menubar is G_TYPE_OBJECT.

Parameter is readable and writable.

register-session

The Gnome::GObject::Value type of property register-session is G_TYPE_BOOLEAN.

Parameter is readable and writable.
Default value is FALSE.

screensaver-active

Whether the screensaver is active

The Gnome::GObject::Value type of property screensaver-active is G_TYPE_BOOLEAN.

Parameter is readable.
Default value is FALSE.

Signals

There are two ways to connect to a signal. The first option you have is to use register-signal() from Gnome::GObject::Object. The second option is to use connect-object() directly from Gnome::GObject::Signal.

First method

The positional arguments of the signal handler are all obligatory as well as their types. The named attributes :$widget and user data are optional.

# handler method
method mouse-event ( GdkEvent $event, :$widget ) { ... }

# connect a signal on window object
my Gnome::Gtk3::Window $w .= new( ... );
$w.register-signal( self, 'mouse-event', 'button-press-event');

Second method

my Gnome::Gtk3::Window $w .= new( ... );
my Callable $handler = sub (
  N-GObject $native, GdkEvent $event, OpaquePointer $data
) {
  ...
}

$w.connect-object( 'button-press-event', $handler);

Also here, the types of positional arguments in the signal handler are important. This is because both methods register-signal() and connect-object() are using the signatures of the handler routines to setup the native call interface.

Supported signals

query-end

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

method handler (
  Int :$_handle_id,
  Gnome::GObject::Object :_widget($application),
  *%user-options
);

$application; the Gnome::Gtk3::Application which emitted the signal
$_handle_id; the registered event handler id

window-added

Emitted when a Gnome::Gtk3::Window is added to application through add-window().

method handler (
  Unknown type GTK_TYPE_WINDOW $window,
  Int :$_handle_id,
  Gnome::GObject::Object :_widget($application),
  *%user-options
);

$application; the Gnome::Gtk3::Application which emitted the signal
$window; the newly-added Gnome::Gtk3::Window
$_handle_id; the registered event handler id

window-removed

Emitted when a Gnome::Gtk3::Window is removed from application, either as a side-effect of being destroyed or explicitly through remove-window().

method handler (
  Unknown type GTK_TYPE_WINDOW $window,
  Int :$_handle_id,
  Gnome::GObject::Object :_widget($application),
  *%user-options
);

$application; the Gnome::Gtk3::Application which emitted the signal
$window; the Gnome::Gtk3::Window that is being removed
$_handle_id; the registered event handler id

Properties

An example of using a string type property of a Gnome::Gtk3::Label object. This is just showing how to set/read a property, not that it is the best way to do it. This is because a) The class initialization often provides some options to set some of the properties and b) the classes provide many methods to modify just those properties. In the case below one can use new(:label('my text label')) or .set-text('my text label').

my Gnome::Gtk3::Label $label .= new;
my Gnome::GObject::Value $gv .= new(:init(G_TYPE_STRING));
$label.get-property( 'label', $gv);
$gv.set-string('my text label');

Supported properties

Active window: active-window

The window which most recently had focus Widget type: GTK-TYPE-WINDOW

The Gnome::GObject::Value type of property active-window is G_TYPE_OBJECT.

The N-GObject for the application menu Widget type: G-TYPE-MENU-MODEL

The Gnome::GObject::Value type of property app-menu is G_TYPE_OBJECT.

The Gnome::GObject::Value type of property screensaver-active is G_TYPE_BOOLEAN.