Class (GI Class)

Gio-2.0GioApplicationSince 2.28

Gio.Application is the core class for application support.

A Gio.Application is the foundation of an application. It wraps some low-level platform-specific services and is intended to act as the foundation for higher-level application classes such as GtkApplication or MxApplication. In general, you should not use this class outside of a higher level framework.

Gio.Application provides convenient life-cycle management by maintaining a "use count" for the primary application instance. The use count can be changed using Gio.Application.hold and Gio.Application.release. If it drops to zero, the application exits. Higher-level classes such as GtkApplication employ the use count to ensure that the application stays alive as long as it has any opened windows.

Another feature that Gio.Application (optionally) provides is process uniqueness. Applications can make use of this functionality by providing a unique application ID. If given, only one application with this ID can be running at a time per session. The session concept is platform-dependent, but corresponds roughly to a graphical desktop login. When your application is launched again, its arguments are passed through platform communication to the already running program. The already running instance of the program is called the "primary instance"; for non-unique applications this is always the current instance. On Linux, the D-Bus session bus is used for communication.

The use of Gio.Application differs from some other commonly-used uniqueness libraries (such as libunique) in important ways. The application is not expected to manually register itself and check if it is the primary instance. Instead, the main() function of a Gio.Application should do very little more than instantiating the application instance, possibly connecting signal handlers, then calling Gio.Application.run. All checks for uniqueness are done internally. If the application is the primary instance then the startup signal is emitted and the mainloop runs. If the application is not the primary instance then a signal is sent to the primary instance and Gio.Application.run promptly returns. See the code examples below.

If used, the expected form of an application identifier is the same as that of a D-Bus well-known bus name. Examples include: com.example.MyApp, org.example.internal_apps.Calculator, org._7_zip.Archiver. For details on valid application identifiers, see Gio.Application.id_is_valid.

On Linux, the application identifier is claimed as a well-known bus name on the user's session bus. This means that the uniqueness of your application is scoped to the current session. It also means that your application may provide additional services (through registration of other object paths) at that bus name. The registration of these object paths should be done with the shared GDBus session bus. Note that due to the internal architecture of GDBus, method calls can be dispatched at any time (even if a main loop is not running). For this reason, you must ensure that any object paths that you wish to register are registered before Gio.Application attempts to acquire the bus name of your application (which happens in Gio.Application.register). Unfortunately, this means that you cannot use Gio.Application.is_remote to decide if you want to register object paths.

Gio.Application also implements the Gio.ActionGroup and Gio.ActionMap interfaces and lets you easily export actions by adding them with Gio.ActionMap.add_action. When invoking an action by calling Gio.ActionGroup.activate_action on the application, it is always invoked in the primary instance. The actions are also exported on the session bus, and GIO provides the Gio.DBusActionGroup wrapper to conveniently access them remotely. GIO provides a Gio.DBusMenuModel wrapper for remote access to exported Gio.MenuModels.

Note: Due to the fact that actions are exported on the session bus, using maybe parameters is not supported, since D-Bus does not support maybe types.

There is a number of different entry points into a Gio.Application:

  • via 'Activate' (i.e. just starting the application)

  • via 'Open' (i.e. opening some files)

  • by handling a command-line

  • via activating an action

The Gio.Application::startup signal lets you handle the application initialization for all of these in a single place.

Regardless of which of these entry points is used to start the application, Gio.Application passes some ‘platform data’ from the launching instance to the primary instance, in the form of a GLib.Variant dictionary mapping strings to variants. To use platform data, override the Gio.Application.before_emit or Gio.Application.after_emit virtual functions in your Gio.Application subclass. When dealing with Gio.ApplicationCommandLine objects, the platform data is directly available via Gio.ApplicationCommandLine.get_cwd, Gio.ApplicationCommandLine.get_environ and Gio.ApplicationCommandLine.get_platform_data.

As the name indicates, the platform data may vary depending on the operating system, but it always includes the current directory (key cwd), and optionally the environment (ie the set of environment variables and their values) of the calling process (key environ). The environment is only added to the platform data if the G_APPLICATION_SEND_ENVIRONMENT flag is set. Gio.Application subclasses can add their own platform data by overriding the Gio.Application.add_platform_data virtual function. For instance, GtkApplication adds startup notification data in this way.

To parse commandline arguments you may handle the Gio.Application::command-line signal or override the Gio.Application.local_command_line virtual function, to parse them in either the primary instance or the local instance, respectively.

For an example of opening files with a Gio.Application, see gapplication-example-open.c.

For an example of using actions with Gio.Application, see gapplication-example-actions.c.

For an example of using extra D-Bus hooks with Gio.Application, see gapplication-example-dbushooks.c.

2.28

Hierarchy (View Summary)

Implements

Index

Constructors

Properties

Accessors

Methods

_init action_added action_enabled_changed action_removed action_state_changed activate activate_action add_action add_action_entries add_main_option add_main_option_entries add_option_group bind_busy_property bind_property bind_property_full block_signal_handler change_action_state connect connect_after disconnect emit force_floating freeze_notify get_action_enabled get_action_parameter_type get_action_state get_action_state_hint get_action_state_type get_application_id get_data get_dbus_connection get_dbus_object_path get_flags get_inactivity_timeout get_is_busy get_is_registered get_is_remote get_property get_qdata get_resource_base_path get_version getv has_action hold is_floating list_actions lookup_action mark_busy notify notify_by_pspec open query_action quit ref ref_sink register release remove_action remove_action_entries run run_dispose runAsync send_notification set set_action_group set_application_id set_data set_default set_flags set_inactivity_timeout set_option_context_description set_option_context_parameter_string set_option_context_summary set_property set_resource_base_path set_version steal_data steal_qdata stop_emission_by_name thaw_notify unbind_busy_property unblock_signal_handler unmark_busy unref vfunc_action_added vfunc_action_enabled_changed vfunc_action_removed vfunc_action_state_changed vfunc_activate vfunc_activate_action vfunc_add_action vfunc_add_platform_data vfunc_after_emit vfunc_before_emit vfunc_change_action_state vfunc_command_line vfunc_constructed vfunc_dbus_register vfunc_dbus_unregister vfunc_dispatch_properties_changed vfunc_dispose vfunc_finalize vfunc_get_action_enabled vfunc_get_action_parameter_type vfunc_get_action_state vfunc_get_action_state_hint vfunc_get_action_state_type vfunc_get_property vfunc_handle_local_options vfunc_has_action vfunc_list_actions vfunc_local_command_line vfunc_lookup_action vfunc_name_lost vfunc_notify vfunc_open vfunc_query_action vfunc_quit_mainloop vfunc_remove_action vfunc_run_mainloop vfunc_set_property vfunc_shutdown vfunc_startup watch_closure withdraw_notification get_default id_is_valid new

Methods - Inherited from GObject

Constructors

Properties

Compile-time signal type information.

This instance property is generated only for TypeScript type checking. It is not defined at runtime and should not be accessed in JS code.

Accessors

  • get inactivity_timeout(): number

    Time (in milliseconds) to stay alive after becoming idle.

    Returns number

    2.28

  • set inactivity_timeout(val: number): void

    Parameters

    • val: number

    Returns void

  • get inactivityTimeout(): number

    Time (in milliseconds) to stay alive after becoming idle.

    Returns number

    2.28

  • set inactivityTimeout(val: number): void

    Parameters

    • val: number

    Returns void

  • get is_busy(): boolean

    Whether the application is currently marked as busy through g_application_mark_busy() or g_application_bind_busy_property().

    Returns boolean

    2.44

  • get is_remote(): boolean

    Whether this application instance is remote.

    Returns boolean

    2.28

  • get isBusy(): boolean

    Whether the application is currently marked as busy through g_application_mark_busy() or g_application_bind_busy_property().

    Returns boolean

    2.44

  • get isRemote(): boolean

    Whether this application instance is remote.

    Returns boolean

    2.28

Methods

  • Emits the Gio.ActionGroup::action-added signal on action_group.

    This function should only be called by Gio.ActionGroup implementations.

    Parameters

    • action_name: string

      the name of an action in the group

    Returns void

  • Emits the Gio.ActionGroup::action-enabled-changed signal on action_group.

    This function should only be called by Gio.ActionGroup implementations.

    Parameters

    • action_name: string

      the name of an action in the group

    • enabled: boolean

      whether the action is now enabled

    Returns void

  • Emits the Gio.ActionGroup::action-removed signal on action_group.

    This function should only be called by Gio.ActionGroup implementations.

    Parameters

    • action_name: string

      the name of an action in the group

    Returns void

  • Activates the application.

    In essence, this results in the Gio.Application::activate signal being emitted in the primary instance.

    The application must be registered before calling this function.

    Returns void

  • Activate the named action within action_group.

    If the action is expecting a parameter, then the correct type of parameter must be given as parameter. If the action is expecting no parameters then parameter must be NULL. See Gio.ActionGroup.get_action_parameter_type.

    If the Gio.ActionGroup implementation supports asynchronous remote activation over D-Bus, this call may return before the relevant D-Bus traffic has been sent, or any replies have been received. In order to block on such asynchronous activation calls, Gio.DBusConnection.flush should be called prior to the code, which depends on the result of the action activation. Without flushing the D-Bus connection, there is no guarantee that the action would have been activated.

    The following code which runs in a remote app instance, shows an example of a ‘quit’ action being activated on the primary app instance over D-Bus. Here Gio.DBusConnection.flush is called before exit(). Without g_dbus_connection_flush(), the ‘quit’ action may fail to be activated on the primary instance.

    // call ‘quit’ action on primary instance
    g_action_group_activate_action (G_ACTION_GROUP (app), "quit", NULL);

    // make sure the action is activated now
    g_dbus_connection_flush (…);

    g_debug ("Application has been terminated. Exiting.");

    exit (0);

    Parameters

    • action_name: string

      the name of the action to activate

    • Optionalparameter: GLib.Variant<any>

      parameters to the activation

    Returns void

  • Adds an action to the action_map.

    If the action map already contains an action with the same name as action then the old action is dropped from the action map.

    The action map takes its own reference on action.

    Parameters

    Returns void

  • Add an option to be handled by application.

    Calling this function is the equivalent of calling g_application_add_main_option_entries() with a single GLib.OptionEntry that has its arg_data member set to null.

    The parsed arguments will be packed into a GLib.VariantDict which is passed to Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options. If Gio.ApplicationFlags.HANDLES_COMMAND_LINE is set, then it will also be sent to the primary instance. See g_application_add_main_option_entries() for more details.

    See GLib.OptionEntry for more documentation of the arguments.

    Parameters

    • long_name: string

      the long name of an option used to specify it in a commandline

    • short_name: number

      the short name of an option

    • flags: OptionFlags

      flags from GLib.OptionFlags

    • arg: OptionArg

      the type of the option, as a GLib.OptionArg

    • description: string

      the description for the option in --help output

    • Optionalarg_description: string

      the placeholder to use for the extra argument parsed by the option in --help output

    Returns void

  • Adds main option entries to be handled by application.

    This function is comparable to g_option_context_add_main_entries().

    After the commandline arguments are parsed, the Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options signal will be emitted. At this point, the application can inspect the values pointed to by arg_data in the given GOptionEntrys.

    Unlike GLib.OptionContext, Gio.Application supports giving a null arg_data for a non-callback GLib.OptionEntry. This results in the argument in question being packed into a GLib.VariantDict which is also passed to Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options, where it can be inspected and modified. If Gio.ApplicationFlags.HANDLES_COMMAND_LINE is set, then the resulting dictionary is sent to the primary instance, where g_application_command_line_get_options_dict() will return it. As it has been passed outside the process at this point, the types of all values in the options dict must be checked before being used. This "packing" is done according to the type of the argument -- booleans for normal flags, strings for strings, bytestrings for filenames, etc. The packing only occurs if the flag is given (ie: we do not pack a "false" GLib.Variant in the case that a flag is missing).

    In general, it is recommended that all commandline arguments are parsed locally. The options dictionary should then be used to transmit the result of the parsing to the primary instance, where g_variant_dict_lookup() can be used. For local options, it is possible to either use arg_data in the usual way, or to consult (and potentially remove) the option from the options dictionary.

    This function is new in GLib 2.40. Before then, the only real choice was to send all of the commandline arguments (options and all) to the primary instance for handling. Gio.Application ignored them completely on the local side. Calling this function "opts in" to the new behaviour, and in particular, means that unrecognized options will be treated as errors. Unrecognized options have never been ignored when Gio.ApplicationFlags.HANDLES_COMMAND_LINE is unset.

    If Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options needs to see the list of filenames, then the use of G_OPTION_REMAINING is recommended. If arg_data is null then G_OPTION_REMAINING can be used as a key into the options dictionary. If you do use G_OPTION_REMAINING then you need to handle these arguments for yourself because once they are consumed, they will no longer be visible to the default handling (which treats them as filenames to be opened).

    It is important to use the proper GVariant format when retrieving the options with g_variant_dict_lookup():

    Parameters

    • entries: OptionEntry[]

      the main options for the application

    Returns void

  • Adds a GLib.OptionGroup to the commandline handling of application.

    This function is comparable to g_option_context_add_group().

    Unlike g_application_add_main_option_entries(), this function does not deal with null arg_data and never transmits options to the primary instance.

    The reason for that is because, by the time the options arrive at the primary instance, it is typically too late to do anything with them. Taking the GTK option group as an example: GTK will already have been initialised by the time the Gio.Application.SignalSignatures.command_line | Gio.Application::command-line handler runs. In the case that this is not the first-running instance of the application, the existing instance may already have been running for a very long time.

    This means that the options from GLib.OptionGroup are only really usable in the case that the instance of the application being run is the first instance. Passing options like --display= or --gdk-debug= on future runs will have no effect on the existing primary instance.

    Calling this function will cause the options in the supplied option group to be parsed, but it does not cause you to be "opted in" to the new functionality whereby unrecognized options are rejected even if Gio.ApplicationFlags.HANDLES_COMMAND_LINE was given.

    Parameters

    Returns void

  • Marks application as busy (see g_application_mark_busy()) while property on object is true.

    The binding holds a reference to application while it is active, but not to object. Instead, the binding is destroyed when object is finalized.

    Parameters

    Returns void

  • Creates a binding between source_property on source and target_property on target.

    Whenever the source_property is changed the target_property is updated using the same value. For instance:

      g_object_bind_property (action, "active", widget, "sensitive", 0);
    

    Will result in the "sensitive" property of the widget GObject.Object instance to be updated with the same value of the "active" property of the action GObject.Object instance.

    If flags contains GObject.BindingFlags.BIDIRECTIONAL then the binding will be mutual: if target_property on target changes then the source_property on source will be updated as well.

    The binding will automatically be removed when either the source or the target instances are finalized. To remove the binding without affecting the source and the target you can just call g_object_unref() on the returned GObject.Binding instance.

    Removing the binding by calling g_object_unref() on it must only be done if the binding, source and target are only used from a single thread and it is clear that both source and target outlive the binding. Especially it is not safe to rely on this if the binding, source or target can be finalized from different threads. Keep another reference to the binding and use g_binding_unbind() instead to be on the safe side.

    A GObject.Object can have multiple bindings.

    Parameters

    Returns GObject.Binding

    the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.

  • Complete version of g_object_bind_property().

    Creates a binding between source_property on source and target_property on target, allowing you to set the transformation functions to be used by the binding.

    If flags contains GObject.BindingFlags.BIDIRECTIONAL then the binding will be mutual: if target_property on target changes then the source_property on source will be updated as well. The transform_from function is only used in case of bidirectional bindings, otherwise it will be ignored

    The binding will automatically be removed when either the source or the target instances are finalized. This will release the reference that is being held on the GObject.Binding instance; if you want to hold on to the GObject.Binding instance, you will need to hold a reference to it.

    To remove the binding, call g_binding_unbind().

    A GObject.Object can have multiple bindings.

    The same user_data parameter will be used for both transform_to and transform_from transformation functions; the notify function will be called once, when the binding is removed. If you need different data for each transformation function, please use g_object_bind_property_with_closures() instead.

    Parameters

    • source_property: string

      the property on source to bind

    • target: GObject.Object

      the target GObject.Object

    • target_property: string

      the property on target to bind

    • flags: GObject.BindingFlags

      flags to pass to GObject.Binding

    • Optionaltransform_to: BindingTransformFunc

      the transformation function from the source to the target, or null to use the default

    • Optionaltransform_from: BindingTransformFunc

      the transformation function from the target to the source, or null to use the default

    • Optionalnotify: DestroyNotify

      a function to call when disposing the binding, to free resources used by the transformation functions, or null if not required

    Returns GObject.Binding

    the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.

  • Creates a binding between source_property on source and target_property on target, allowing you to set the transformation functions to be used by the binding.

    This function is the language bindings friendly version of g_object_bind_property_full(), using GClosures instead of function pointers.

    Parameters

    • ...args: never[]

      the property on source to bind

    Returns any

    the GObject.Binding instance representing the binding between the two GObject.Object instances. The binding is released whenever the GObject.Binding reference count reaches zero.

  • Disconnects a handler from an instance so it will not be called during any future or currently ongoing emissions of the signal it has been connected to.

    Parameters

    • id: number

      Handler ID of the handler to be disconnected

    Returns void

  • This function is intended for GObject.Object implementations to re-enforce a [floating][floating-ref] object reference. Doing this is seldom required: all GInitiallyUnowneds are created with a floating reference which usually just needs to be sunken by calling g_object_ref_sink().

    Returns void

  • Increases the freeze count on object. If the freeze count is non-zero, the emission of "notify" signals on object is stopped. The signals are queued until the freeze count is decreased to zero. Duplicate notifications are squashed so that at most one GObject.Object::notify signal is emitted for each property modified while the object is frozen.

    This is necessary for accessors that modify multiple properties to prevent premature notification while the object is still being modified.

    Returns void

  • Checks if the named action within action_group is currently enabled.

    An action must be enabled in order to be activated or in order to have its state changed from outside callers.

    Parameters

    • action_name: string

      the name of the action to query

    Returns boolean

    whether the action is currently enabled

  • Queries the type of the parameter that must be given when activating the named action within action_group.

    When activating the action using Gio.ActionGroup.activate_action, the GLib.Variant given to that function must be of the type returned by this function.

    In the case that this function returns NULL, you must not give any GLib.Variant, but NULL instead.

    The parameter type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different parameter type.

    Parameters

    • action_name: string

      the name of the action to query

    Returns GLib.VariantType<any>

    the parameter type

  • Requests a hint about the valid range of values for the state of the named action within action_group.

    If NULL is returned it either means that the action is not stateful or that there is no hint about the valid range of values for the state of the action.

    If a GLib.Variant array is returned then each item in the array is a possible value for the state. If a GLib.Variant pair (ie: two-tuple) is returned then the tuple specifies the inclusive lower and upper bound of valid values for the state.

    In any case, the information is merely a hint. It may be possible to have a state value outside of the hinted range and setting a value within the range may fail.

    The return value (if non-NULL) should be freed with GLib.Variant.unref when it is no longer required.

    Parameters

    • action_name: string

      the name of the action to query

    Returns GLib.Variant<any>

    the state range hint

  • Gets the unique identifier for application.

    Returns string

    the identifier for application, owned by application

  • Gets a named field from the objects table of associations (see g_object_set_data()).

    Parameters

    • key: string

      name of the key for that association

    Returns any

    the data if found, or null if no such data exists.

  • Gets the Gio.DBusConnection being used by the application, or null.

    If Gio.Application is using its D-Bus backend then this function will return the Gio.DBusConnection being used for uniqueness and communication with the desktop environment and other instances of the application.

    If Gio.Application is not using D-Bus then this function will return null. This includes the situation where the D-Bus backend would normally be in use but we were unable to connect to the bus.

    This function must not be called before the application has been registered. See g_application_get_is_registered().

    Returns Gio.DBusConnection

    a Gio.DBusConnection, or null

  • Gets the D-Bus object path being used by the application, or null.

    If Gio.Application is using its D-Bus backend then this function will return the D-Bus object path that Gio.Application is using. If the application is the primary instance then there is an object published at this path. If the application is not the primary instance then the result of this function is undefined.

    If Gio.Application is not using D-Bus then this function will return null. This includes the situation where the D-Bus backend would normally be in use but we were unable to connect to the bus.

    This function must not be called before the application has been registered. See g_application_get_is_registered().

    Returns string

    the object path, or null

  • Gets the current inactivity timeout for the application.

    This is the amount of time (in milliseconds) after the last call to g_application_release() before the application stops running.

    Returns number

    the timeout, in milliseconds

  • Gets the application's current busy state, as set through g_application_mark_busy() or g_application_bind_busy_property().

    Returns boolean

    true if application is currently marked as busy

  • Checks if application is registered.

    An application is registered if g_application_register() has been successfully called.

    Returns boolean

    true if application is registered

  • Checks if application is remote.

    If application is remote then it means that another instance of application already exists (the 'primary' instance). Calls to perform actions on application will result in the actions being performed by the primary instance.

    The value of this property cannot be accessed before g_application_register() has been called. See g_application_get_is_registered().

    Returns boolean

    true if application is remote

  • Gets a property of an object.

    The value can be:

    • an empty GObject.Value initialized by G_VALUE_INIT, which will be automatically initialized with the expected type of the property (since GLib 2.60)
    • a GObject.Value initialized with the expected type of the property
    • a GObject.Value initialized with a type to which the expected type of the property can be transformed

    In general, a copy is made of the property contents and the caller is responsible for freeing the memory by calling GObject.Value.unset.

    Note that GObject.Object.get_property is really intended for language bindings, GObject.Object.get is much more convenient for C programming.

    Parameters

    • property_name: string

      The name of the property to get

    • value: any

      Return location for the property value. Can be an empty GObject.Value initialized by G_VALUE_INIT (auto-initialized with expected type since GLib 2.60), a GObject.Value initialized with the expected property type, or a GObject.Value initialized with a transformable type

    Returns any

  • Gets the resource base path of application.

    See g_application_set_resource_base_path() for more information.

    Returns string

    the base resource path, if one is set

  • Gets the version of application.

    Returns string

    the version of application

  • Gets n_properties properties for an object. Obtained properties will be set to values. All properties must be valid. Warnings will be emitted and undefined behaviour may result if invalid properties are passed in.

    Parameters

    • names: string[]

      the names of each property to get

    • values: any[]

      the values of each property to get

    Returns void

  • Checks if the named action exists within action_group.

    Parameters

    • action_name: string

      the name of the action to check for

    Returns boolean

    whether the named action exists

  • Increases the use count of application.

    Use this function to indicate that the application has a reason to continue to run. For example, g_application_hold() is called by GTK when a toplevel window is on the screen.

    To cancel the hold, call g_application_release().

    Returns void

  • Lists the actions contained within action_group.

    The caller is responsible for freeing the list with GLib.strfreev when it is no longer required.

    Returns string[]

    a NULL-terminated array of the names of the actions in the group

  • Increases the busy count of application.

    Use this function to indicate that the application is busy, for instance while a long running operation is pending.

    The busy state will be exposed to other processes, so a session shell will use that information to indicate the state to the user (e.g. with a spinner).

    To cancel the busy indication, use g_application_unmark_busy().

    The application must be registered before calling this function.

    Returns void

  • Emits a "notify" signal for the property property_name on object.

    When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

    Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

    Parameters

    • property_name: string

      the name of a property installed on the class of object.

    Returns void

  • Emits a "notify" signal for the property specified by pspec on object.

    This function omits the property name lookup, hence it is faster than g_object_notify().

    One way to avoid using g_object_notify() from within the class that registered the properties, and using g_object_notify_by_pspec() instead, is to store the GParamSpec used with g_object_class_install_property() inside a static array, e.g.:

      typedef enum
    {
    PROP_FOO = 1,
    PROP_LAST
    } MyObjectProperty;

    static GParamSpec *properties[PROP_LAST];

    static void
    my_object_class_init (MyObjectClass *klass)
    {
    properties[PROP_FOO] = g_param_spec_int ("foo", NULL, NULL,
    0, 100,
    50,
    G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS);
    g_object_class_install_property (gobject_class,
    PROP_FOO,
    properties[PROP_FOO]);
    }

    and then notify a change on the "foo" property with:

      g_object_notify_by_pspec (self, properties[PROP_FOO]);
    

    Parameters

    Returns void

  • Opens the given files.

    In essence, this results in the Gio.Application::open signal being emitted in the primary instance.

    n_files must be greater than zero.

    hint is simply passed through to the ::open signal. It is intended to be used by applications that have multiple modes for opening files (eg: "view" vs "edit", etc). Unless you have a need for this functionality, you should use "".

    The application must be registered before calling this function and it must have the Gio.ApplicationFlags.HANDLES_OPEN flag set.

    Parameters

    • files: Gio.File[]

      an array of GFiles to open

    • hint: string

      a hint (or ""), but never null

    Returns void

  • Immediately quits the application.

    Upon return to the mainloop, g_application_run() will return, calling only the 'shutdown' function before doing so.

    The hold count is ignored. Take care if your code has called g_application_hold() on the application and is therefore still expecting it to exist. (Note that you may have called g_application_hold() indirectly, for example through gtk_application_add_window().)

    The result of calling g_application_run() again after it returns is unspecified.

    Returns void

  • Increases the reference count of object.

    Since GLib 2.56, if GLIB_VERSION_MAX_ALLOWED is 2.56 or greater, the type of object will be propagated to the return type (using the GCC typeof() extension), so any casting the caller needs to do on the return type must be explicit.

    Returns GObject.Object

    the same object

  • Increase the reference count of object, and possibly remove the [floating][floating-ref] reference, if object has a floating reference.

    In other words, if the object is floating, then this call "assumes ownership" of the floating reference, converting it to a normal reference by clearing the floating flag while leaving the reference count unchanged. If the object is not floating, then this call adds a new normal reference increasing the reference count by one.

    Since GLib 2.56, the type of object will be propagated to the return type under the same conditions as for g_object_ref().

    Returns GObject.Object

    object

  • Attempts registration of the application.

    This is the point at which the application discovers if it is the primary instance or merely acting as a remote for an already-existing primary instance. This is implemented by attempting to acquire the application identifier as a unique bus name on the session bus using GDBus.

    If there is no application ID or if Gio.ApplicationFlags.NON_UNIQUE was given, then this process will always become the primary instance.

    Due to the internal architecture of GDBus, method calls can be dispatched at any time (even if a main loop is not running). For this reason, you must ensure that any object paths that you wish to register are registered before calling this function.

    If the application has already been registered then true is returned with no work performed.

    The Gio.Application::startup signal is emitted if registration succeeds and application is the primary instance (including the non-unique case).

    In the event of an error (such as cancellable being cancelled, or a failure to connect to the session bus), false is returned and error is set appropriately.

    Note: the return value of this function is not an indicator that this instance is or is not the primary instance of the application. See g_application_get_is_remote() for that.

    Parameters

    Returns boolean

    true if registration succeeded

  • Decrease the use count of application.

    When the use count reaches zero, the application will stop running.

    Never call this function except to cancel the effect of a previous call to g_application_hold().

    Returns void

  • Removes the named action from the action map.

    If no action of this name is in the map then nothing happens.

    Parameters

    • action_name: string

      the name of the action

    Returns void

  • Runs the application.

    This function is intended to be run from main() and its return value is intended to be returned by main(). Although you are expected to pass the argc, argv parameters from main() to this function, it is possible to pass null if argv is not available or commandline handling is not required. Note that on Windows, argc and argv are ignored, and g_win32_get_command_line() is called internally (for proper support of Unicode commandline arguments).

    Gio.Application will attempt to parse the commandline arguments. You can add commandline flags to the list of recognised options by way of g_application_add_main_option_entries(). After this, the Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options signal is emitted, from which the application can inspect the values of its GOptionEntrys.

    Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options is a good place to handle options such as --version, where an immediate reply from the local process is desired (instead of communicating with an already-running instance). A Gio.Application.SignalSignatures.handle_local_options | Gio.Application::handle-local-options handler can stop further processing by returning a non-negative value, which then becomes the exit status of the process.

    What happens next depends on the flags: if Gio.ApplicationFlags.HANDLES_COMMAND_LINE was specified then the remaining commandline arguments are sent to the primary instance, where a Gio.Application.SignalSignatures.command_line | Gio.Application::command-line signal is emitted. Otherwise, the remaining commandline arguments are assumed to be a list of files. If there are no files listed, the application is activated via the Gio.Application::activate signal. If there are one or more files, and Gio.ApplicationFlags.HANDLES_OPEN was specified then the files are opened via the Gio.Application::open signal.

    If you are interested in doing more complicated local handling of the commandline then you should implement your own Gio.Application subclass and override local_command_line(). In this case, you most likely want to return true from your local_command_line() implementation to suppress the default handling. See [gapplication-example-cmdline2.c][https://gitlab.gnome.org/GNOME/glib/-/blob/HEAD/gio/tests/gapplication-example-cmdline2.c] for an example.

    If, after the above is done, the use count of the application is zero then the exit status is returned immediately. If the use count is non-zero then the default main context is iterated until the use count falls to zero, at which point 0 is returned.

    If the Gio.ApplicationFlags.IS_SERVICE flag is set, then the service will run for as much as 10 seconds with a use count of zero while waiting for the message that caused the activation to arrive. After that, if the use count falls to zero the application will exit immediately, except in the case that g_application_set_inactivity_timeout() is in use.

    This function sets the prgname (g_set_prgname()), if not already set, to the basename of argv[0].

    Much like g_main_loop_run(), this function will acquire the main context for the duration that the application is running.

    Since 2.40, applications that are not explicitly flagged as services or launchers (ie: neither Gio.ApplicationFlags.IS_SERVICE or Gio.ApplicationFlags.IS_LAUNCHER are given as flags) will check (from the default handler for local_command_line) if "--gapplication-service" was given in the command line. If this flag is present then normal commandline processing is interrupted and the Gio.ApplicationFlags.IS_SERVICE flag is set. This provides a "compromise" solution whereby running an application directly from the commandline will invoke it in the normal way (which can be useful for debugging) while still allowing applications to be D-Bus activated in service mode. The D-Bus service file should invoke the executable with "--gapplication-service" as the sole commandline argument. This approach is suitable for use by most graphical applications but should not be used from applications like editors that need precise control over when processes invoked via the commandline will exit and what their exit status will be.

    Parameters

    • Optionalargv: string[]

      the argv from main(), or null

    Returns number

    the exit status

  • Similar to Gio.Application.run but return a Promise which resolves when the main loop ends, instead of blocking while the main loop runs. This helps avoid the situation where Promises never resolved if you didn't run the application inside a callback.

    Parameters

    • Optionalargv: string[]

      Commandline arguments

    Returns Promise<number>

  • Sends a notification on behalf of application to the desktop shell. There is no guarantee that the notification is displayed immediately, or even at all.

    Notifications may persist after the application exits. It will be D-Bus-activated when the notification or one of its actions is activated.

    Modifying notification after this call has no effect. However, the object can be reused for a later call to this function.

    id may be any string that uniquely identifies the event for the application. It does not need to be in any special format. For example, "new-message" might be appropriate for a notification about new messages.

    If a previous notification was sent with the same id, it will be replaced with notification and shown again as if it was a new notification. This works even for notifications sent from a previous execution of the application, as long as id is the same string.

    id may be NULL, but it is impossible to replace or withdraw notifications without an id.

    If notification is no longer relevant, it can be withdrawn with Gio.Application.withdraw_notification.

    It is an error to call this function if application has no application ID.

    Parameters

    Returns void

  • Sets multiple properties of an object at once. The properties argument should be a dictionary mapping property names to values.

    Parameters

    • properties: { [key: string]: any }

      Object containing the properties to set

    Returns void

  • Sets the unique identifier for application.

    The application id can only be modified if application has not yet been registered.

    If non-null, the application id must be valid. See g_application_id_is_valid().

    Parameters

    • Optionalapplication_id: string

      the identifier for application

    Returns void

  • Each object carries around a table of associations from strings to pointers. This function lets you set an association.

    If the object already had an association with that name, the old association will be destroyed.

    Internally, the key is converted to a GLib.Quark using g_quark_from_string(). This means a copy of key is kept permanently (even after object has been finalized) — so it is recommended to only use a small, bounded set of values for key in your program, to avoid the GLib.Quark storage growing unbounded.

    Parameters

    • key: string

      name of the key

    • Optionaldata: any

      data to associate with that key

    Returns void

  • Sets or unsets the default application for the process, as returned by g_application_get_default().

    This function does not take its own reference on application. If application is destroyed then the default application will revert back to null.

    Returns void

  • Sets the current inactivity timeout for the application.

    This is the amount of time (in milliseconds) after the last call to g_application_release() before the application stops running.

    This call has no side effects of its own. The value set here is only used for next time g_application_release() drops the use count to zero. Any timeouts currently in progress are not impacted.

    Parameters

    • inactivity_timeout: number

      the timeout, in milliseconds

    Returns void

  • Adds a description to the application option context.

    See g_option_context_set_description() for more information.

    Parameters

    • Optionaldescription: string

      a string to be shown in --help output after the list of options, or null

    Returns void

  • Sets the parameter string to be used by the commandline handling of application.

    This function registers the argument to be passed to g_option_context_new() when the internal GLib.OptionContext of application is created.

    See g_option_context_new() for more information about parameter_string.

    Parameters

    • Optionalparameter_string: string

      a string which is displayed in the first line of --help output, after the usage summary programname [OPTION...].

    Returns void

  • Adds a summary to the application option context.

    See g_option_context_set_summary() for more information.

    Parameters

    • Optionalsummary: string

      a string to be shown in --help output before the list of options, or null

    Returns void

  • Sets (or unsets) the base resource path of application.

    The path is used to automatically load various [application resources]Gio.Resource such as menu layouts and action descriptions. The various types of resources will be found at fixed names relative to the given base path.

    By default, the resource base path is determined from the application ID by prefixing '/' and replacing each '.' with '/'. This is done at the time that the Gio.Application object is constructed. Changes to the application ID after that point will not have an impact on the resource base path.

    As an example, if the application has an ID of "org.example.app" then the default resource base path will be "/org/example/app". If this is a GtkApplication (and you have not manually changed the path) then Gtk will then search for the menus of the application at "/org/example/app/gtk/menus.ui".

    See Gio.Resource for more information about adding resources to your application.

    You can disable automatic resource loading functionality by setting the path to null.

    Changing the resource base path once the application is running is not recommended. The point at which the resource path is consulted for forming paths for various purposes is unspecified. When writing a sub-class of Gio.Application you should either set the Gio.Application.resource_base_path property at construction time, or call this function during the instance initialization. Alternatively, you can call this function in the Gio.ApplicationClass.startup virtual function, before chaining up to the parent implementation.

    Parameters

    • Optionalresource_path: string

      the resource path to use

    Returns void

  • Sets the version number of application. This will be used to implement a --version command line argument

    The application version can only be modified if application has not yet been registered.

    Parameters

    • version: string

      the version of application

    Returns void

  • Remove a specified datum from the object's data associations, without invoking the association's destroy handler.

    Parameters

    • key: string

      name of the key

    Returns any

    the data if found, or null if no such data exists.

  • This function gets back user data pointers stored via g_object_set_qdata() and removes the data from object without invoking its destroy() function (if any was set). Usually, calling this function is only required to update user data pointers with a destroy notifier, for example:

    void
    object_add_to_user_list (GObject *object,
    const gchar *new_string)
    {
    // the quark, naming the object data
    GQuark quark_string_list = g_quark_from_static_string ("my-string-list");
    // retrieve the old string list
    GList *list = g_object_steal_qdata (object, quark_string_list);

    // prepend new string
    list = g_list_prepend (list, g_strdup (new_string));
    // this changed 'list', so we need to set it again
    g_object_set_qdata_full (object, quark_string_list, list, free_string_list);
    }
    static void
    free_string_list (gpointer data)
    {
    GList *node, *list = data;

    for (node = list; node; node = node->next)
    g_free (node->data);
    g_list_free (list);
    }

    Using g_object_get_qdata() in the above example, instead of g_object_steal_qdata() would have left the destroy function set, and thus the partial string list would have been freed upon g_object_set_qdata_full().

    Parameters

    • quark: number

      A GLib.Quark, naming the user data pointer

    Returns any

    The user data pointer set, or null

  • Reverts the effect of a previous call to g_object_freeze_notify(). The freeze count is decreased on object and when it reaches zero, queued "notify" signals are emitted.

    Duplicate notifications for each property are squashed so that at most one GObject.Object::notify signal is emitted for each property, in the reverse order in which they have been queued.

    It is an error to call this function when the freeze count is zero.

    Returns void

  • Destroys a binding between property and the busy state of application that was previously created with g_application_bind_busy_property().

    Parameters

    Returns void

  • Decreases the busy count of application.

    When the busy count reaches zero, the new state will be propagated to other processes.

    This function must only be called to cancel the effect of a previous call to g_application_mark_busy().

    Returns void

  • Decreases the reference count of object. When its reference count drops to 0, the object is finalized (i.e. its memory is freed).

    If the pointer to the GObject.Object may be reused in future (for example, if it is an instance variable of another object), it is recommended to clear the pointer to null rather than retain a dangling pointer to a potentially invalid GObject.Object instance. Use g_clear_object() for this.

    Returns void

  • Emits the Gio.ActionGroup::action-enabled-changed signal on action_group.

    This function should only be called by Gio.ActionGroup implementations.

    Parameters

    • action_name: string

      the name of an action in the group

    • enabled: boolean

      whether the action is now enabled

    Returns void

  • Activates the application.

    In essence, this results in the Gio.Application::activate signal being emitted in the primary instance.

    The application must be registered before calling this function.

    Returns void

  • Activate the named action within action_group.

    If the action is expecting a parameter, then the correct type of parameter must be given as parameter. If the action is expecting no parameters then parameter must be NULL. See Gio.ActionGroup.get_action_parameter_type.

    If the Gio.ActionGroup implementation supports asynchronous remote activation over D-Bus, this call may return before the relevant D-Bus traffic has been sent, or any replies have been received. In order to block on such asynchronous activation calls, Gio.DBusConnection.flush should be called prior to the code, which depends on the result of the action activation. Without flushing the D-Bus connection, there is no guarantee that the action would have been activated.

    The following code which runs in a remote app instance, shows an example of a ‘quit’ action being activated on the primary app instance over D-Bus. Here Gio.DBusConnection.flush is called before exit(). Without g_dbus_connection_flush(), the ‘quit’ action may fail to be activated on the primary instance.

    // call ‘quit’ action on primary instance
    g_action_group_activate_action (G_ACTION_GROUP (app), "quit", NULL);

    // make sure the action is activated now
    g_dbus_connection_flush (…);

    g_debug ("Application has been terminated. Exiting.");

    exit (0);

    Parameters

    • action_name: string

      the name of the action to activate

    • Optionalparameter: GLib.Variant<any>

      parameters to the activation

    Returns void

  • invoked on the primary instance after 'activate', 'open', 'command-line' or any action invocation, gets the 'platform data' from the calling instance. Must chain up

    Parameters

    Returns void

  • invoked on the primary instance before 'activate', 'open', 'command-line' or any action invocation, gets the 'platform data' from the calling instance. Must chain up

    Parameters

    Returns void

  • the constructed function is called by g_object_new() as the final step of the object creation process. At the point of the call, all construction properties have been set on the object. The purpose of this call is to allow for object initialisation steps that can only be performed after construction properties have been set. constructed implementors should chain up to the constructed call of their parent class to allow it to complete its initialisation.

    Returns void

  • invoked locally during registration, if the application is using its D-Bus backend. You can use this to export extra objects on the bus, that need to exist before the application tries to own the bus name. The function is passed the Gio.DBusConnection to to session bus, and the object path that Gio.Application will use to export its D-Bus API. If this function returns true, registration will proceed; otherwise registration will abort. Since: 2.34

    Parameters

    Returns boolean

  • invoked locally during unregistration, if the application is using its D-Bus backend. Use this to undo anything done by the dbus_register vfunc. Since: 2.34

    Parameters

    Returns void

  • the dispose function is supposed to drop all references to other objects, but keep the instance otherwise intact, so that client method invocations still work. It may be run multiple times (due to reference loops). Before returning, dispose should chain up to the dispose method of the parent class.

    Returns void

  • Checks if the named action within action_group is currently enabled.

    An action must be enabled in order to be activated or in order to have its state changed from outside callers.

    Parameters

    • action_name: string

      the name of the action to query

    Returns boolean

  • Queries the type of the parameter that must be given when activating the named action within action_group.

    When activating the action using Gio.ActionGroup.activate_action, the GLib.Variant given to that function must be of the type returned by this function.

    In the case that this function returns NULL, you must not give any GLib.Variant, but NULL instead.

    The parameter type of a particular action will never change but it is possible for an action to be removed and for a new action to be added with the same name but a different parameter type.

    Parameters

    • action_name: string

      the name of the action to query

    Returns GLib.VariantType<any>

  • Requests a hint about the valid range of values for the state of the named action within action_group.

    If NULL is returned it either means that the action is not stateful or that there is no hint about the valid range of values for the state of the action.

    If a GLib.Variant array is returned then each item in the array is a possible value for the state. If a GLib.Variant pair (ie: two-tuple) is returned then the tuple specifies the inclusive lower and upper bound of valid values for the state.

    In any case, the information is merely a hint. It may be possible to have a state value outside of the hinted range and setting a value within the range may fail.

    The return value (if non-NULL) should be freed with GLib.Variant.unref when it is no longer required.

    Parameters

    • action_name: string

      the name of the action to query

    Returns GLib.Variant<any>

  • Checks if the named action exists within action_group.

    Parameters

    • action_name: string

      the name of the action to check for

    Returns boolean

  • This virtual function is always invoked in the local instance. It gets passed a pointer to a null-terminated copy of argv and is expected to remove arguments that it handled (shifting up remaining arguments).

    The last argument to local_command_line() is a pointer to the status variable which can used to set the exit status that is returned from g_application_run().

    See g_application_run() for more details on Gio.Application startup.

    Parameters

    • _arguments: string[]

      array of command line arguments

    Returns [boolean, string[], number]

  • invoked when another instance is taking over the name. Since: 2.60

    Returns boolean

  • Emits a "notify" signal for the property property_name on object.

    When possible, eg. when signaling a property change from within the class that registered the property, you should use g_object_notify_by_pspec() instead.

    Note that emission of the notify signal may be blocked with g_object_freeze_notify(). In this case, the signal emissions are queued and will be emitted (in reverse order) when g_object_thaw_notify() is called.

    Parameters

    Returns void

  • Opens the given files.

    In essence, this results in the Gio.Application::open signal being emitted in the primary instance.

    n_files must be greater than zero.

    hint is simply passed through to the ::open signal. It is intended to be used by applications that have multiple modes for opening files (eg: "view" vs "edit", etc). Unless you have a need for this functionality, you should use "".

    The application must be registered before calling this function and it must have the Gio.ApplicationFlags.HANDLES_OPEN flag set.

    Parameters

    • files: Gio.File[]

      an array of GFiles to open

    • hint: string

      a hint (or ""), but never null

    Returns void

  • Used to be invoked on the primary instance when the use count of the application drops to zero (and after any inactivity timeout, if requested). Not used anymore since 2.32

    Returns void

  • Removes the named action from the action map.

    If no action of this name is in the map then nothing happens.

    Parameters

    • action_name: string

      the name of the action

    Returns void

  • Used to be invoked on the primary instance from g_application_run() if the use-count is non-zero. Since 2.32, GApplication is iterating the main context directly and is not using run_mainloop anymore

    Returns void

  • the generic setter for all properties of this type. Should be overridden for every type with properties. If implementations of set_property don't emit property change notification explicitly, this will be done implicitly by the type system. However, if the notify signal is emitted explicitly, the type system will not emit it a second time.

    Parameters

    Returns void

  • invoked only on the registered primary instance immediately after the main loop terminates

    Returns void

  • invoked on the primary instance immediately after registration

    Returns void

  • This function essentially limits the life time of the closure to the life time of the object. That is, when the object is finalized, the closure is invalidated by calling g_closure_invalidate() on it, in order to prevent invocations of the closure with a finalized (nonexisting) object. Also, g_object_ref() and g_object_unref() are added as marshal guards to the closure, to ensure that an extra reference count is held on object during invocation of the closure. Usually, this function will be called on closures that use this object as closure data.

    Parameters

    Returns void

  • Withdraws a notification that was sent with g_application_send_notification().

    This call does nothing if a notification with id doesn't exist or the notification was never sent.

    This function works even for notifications sent in previous executions of this application, as long id is the same as it was for the sent notification.

    Note that notifications are dismissed when the user clicks on one of the buttons in a notification or triggers its default action, so there is no need to explicitly withdraw the notification in that case.

    Parameters

    • id: string

      id of a previously sent notification

    Returns void

  • Checks if application_id is a valid application identifier.

    A valid ID is required for calls to g_application_new() and g_application_set_application_id().

    Application identifiers follow the same format as D-Bus well-known bus names. For convenience, the restrictions on application identifiers are reproduced here:

    • Application identifiers are composed of 1 or more elements separated by a period (.) character. All elements must contain at least one character.

    • Each element must only contain the ASCII characters [A-Z][a-z][0-9]_-, with - discouraged in new application identifiers. Each element must not begin with a digit.

    • Application identifiers must contain at least one . (period) character (and thus at least two elements).

    • Application identifiers must not begin with a . (period) character.

    • Application identifiers must not exceed 255 characters.

    Note that the hyphen (-) character is allowed in application identifiers, but is problematic or not allowed in various specifications and APIs that refer to D-Bus, such as Flatpak application IDs, the DBusActivatable interface in the Desktop Entry Specification, and the convention that an application's "main" interface and object path resemble its application identifier and bus name. To avoid situations that require special-case handling, it is recommended that new application identifiers consistently replace hyphens with underscores.

    Like D-Bus interface names, application identifiers should start with the reversed DNS domain name of the author of the interface (in lower-case), and it is conventional for the rest of the application identifier to consist of words run together, with initial capital letters.

    As with D-Bus interface names, if the author's DNS domain name contains hyphen/minus characters they should be replaced by underscores, and if it contains leading digits they should be escaped by prepending an underscore. For example, if the owner of 7-zip.org used an application identifier for an archiving application, it might be named org._7_zip.Archiver.

    Parameters

    • application_id: string

      a potential application identifier

    Returns boolean

Methods - Inherited from GObject

  • Add a property to an interface; this is only useful for interfaces that are added to GObject-derived types. Adding a property to an interface forces all objects classes with that interface to have a compatible property. The compatible property could be a newly created GObject.ParamSpec, but normally g_object_class_override_property() will be used so that the object class only needs to provide an implementation and inherits the property description, default value, bounds, and so forth from the interface property.

    This function is meant to be called from the interface's default vtable initialization function (the class_init member of GObject.TypeInfo.) It must not be called after after class_init has been called for any object types implementing this interface.

    If pspec is a floating reference, it will be consumed.

    Parameters

    Returns void

  • Parameters

    • property_id: number

      the new property ID

    • name: string

      the name of a property registered in a parent class or in an interface of this class.

    Returns void

Interfaces

ConstructorProps
SignalSignatures