Gio.AppLaunchContext¶

class — extends GObject.Object

Integrating the launch with the launching application. This is used to handle for instance startup notification and launching the new application on the same screen as the launching window.

Constructors¶

new¶

@classmethod
def new(cls) -> AppLaunchContext

Creates a new application launch context. This is not normally used, instead you instantiate a subclass of this, such as GdkAppLaunchContext.

Methods¶

get_display¶

def get_display(self, info: AppInfo, files: list[File]) -> str | None

Gets the display string for the context. This is used to ensure new applications are started on the same display as the launching application, by setting the DISPLAY environment variable.

Parameters:

info — the app info
files — a list of File objects

get_environment¶

def get_environment(self) -> list[str]

Gets the complete environment variable list to be passed to the child process when context is used to launch an application. This is a NULL-terminated array of strings, where each string has the form KEY=VALUE.

get_startup_notify_id¶

def get_startup_notify_id(self, info: AppInfo | None = ..., files: list[File] | None = ...) -> str | None

Initiates startup notification for the application and returns the XDG_ACTIVATION_TOKEN or DESKTOP_STARTUP_ID for the launched operation, if supported.

The returned token may be referred to equivalently as an ‘activation token’ (using Wayland terminology) or a ‘startup sequence ID’ (using X11 terminology). The two are interoperable.

Activation tokens are defined in the XDG Activation Protocol, and startup notification IDs are defined in the freedesktop.org Startup Notification Protocol.

Support for the XDG Activation Protocol was added in GLib 2.76. Since GLib 2.82 info and files can be NULL. If that’s not supported by the backend, the returned token will be NULL.

Parameters:

info — the app info
files — a list of File objects

launch_failed¶

def launch_failed(self, startup_notify_id: str) -> None

Called when an application has failed to launch, so that it can cancel the application startup notification started in AppLaunchContext.get_startup_notify_id.

Parameters:

startup_notify_id — the startup notification id that was returned by AppLaunchContext.get_startup_notify_id.

setenv¶

def setenv(self, variable: str | bytes | os.PathLike[str] | os.PathLike[bytes], value: str | bytes | os.PathLike[str] | os.PathLike[bytes]) -> None

Arranges for variable to be set to value in the child’s environment when context is used to launch an application.

Parameters:

variable — the environment variable to set
value — the value for to set the variable to.

unsetenv¶

def unsetenv(self, variable: str | bytes | os.PathLike[str] | os.PathLike[bytes]) -> None

Arranges for variable to be unset in the child’s environment when context is used to launch an application.

Parameters:

variable — the environment variable to remove

Virtual methods¶

do_get_display¶

def do_get_display(self, info: AppInfo, files: list[File]) -> str | None

Gets the display string for the context. This is used to ensure new applications are started on the same display as the launching application, by setting the DISPLAY environment variable.

Parameters:

info — the app info
files — a list of File objects

do_get_startup_notify_id¶

def do_get_startup_notify_id(self, info: AppInfo | None = ..., files: list[File] | None = ...) -> str | None

Initiates startup notification for the application and returns the XDG_ACTIVATION_TOKEN or DESKTOP_STARTUP_ID for the launched operation, if supported.

The returned token may be referred to equivalently as an ‘activation token’ (using Wayland terminology) or a ‘startup sequence ID’ (using X11 terminology). The two are interoperable.

Activation tokens are defined in the XDG Activation Protocol, and startup notification IDs are defined in the freedesktop.org Startup Notification Protocol.

Support for the XDG Activation Protocol was added in GLib 2.76. Since GLib 2.82 info and files can be NULL. If that’s not supported by the backend, the returned token will be NULL.

Parameters:

info — the app info
files — a list of File objects

do_launch_failed¶

def do_launch_failed(self, startup_notify_id: str) -> None

Called when an application has failed to launch, so that it can cancel the application startup notification started in AppLaunchContext.get_startup_notify_id.

Parameters:

startup_notify_id — the startup notification id that was returned by AppLaunchContext.get_startup_notify_id.

do_launch_started¶

def do_launch_started(self, info: AppInfo, platform_data: GLib.Variant) -> None

do_launched¶

def do_launched(self, info: AppInfo, platform_data: GLib.Variant) -> None

Signals¶

launch-failed¶

def on_launch_failed(self, startup_notify_id: str) -> None: ...

The AppLaunchContext.launch-failed signal is emitted when a AppInfo launch fails. The startup notification id is provided, so that the launcher can cancel the startup notification.

Because a launch operation may involve spawning multiple instances of the target application, you should expect this signal to be emitted multiple times, one for each spawned instance.

launch-started¶

def on_launch_started(self, info: AppInfo, platform_data: GLib.Variant | None) -> None: ...

The AppLaunchContext.launch-started signal is emitted when a AppInfo is about to be launched. If non-null the platform_data is an GVariant dictionary mapping strings to variants (ie a{sv}), which contains additional, platform-specific data about this launch. On UNIX, at least the startup-notification-id keys will be present.

The value of the startup-notification-id key (type s) is a startup notification ID corresponding to the format from the startup-notification specification. It allows tracking the progress of the launchee through startup.

It is guaranteed that this signal is followed by either a AppLaunchContext.launched or AppLaunchContext.launch-failed signal.

Because a launch operation may involve spawning multiple instances of the target application, you should expect this signal to be emitted multiple times, one for each spawned instance.

launched¶

def on_launched(self, info: AppInfo, platform_data: GLib.Variant) -> None: ...

The AppLaunchContext.launched signal is emitted when a AppInfo is successfully launched.

Because a launch operation may involve spawning multiple instances of the target application, you should expect this signal to be emitted multiple times, one time for each spawned instance.

The platform_data is an GVariant dictionary mapping strings to variants (ie a{sv}), which contains additional, platform-specific data about this launch. On UNIX, at least the pid and startup-notification-id keys will be present.

Since 2.72 the pid may be 0 if the process id wasn’t known (for example if the process was launched via D-Bus). The pid may not be set at all in subsequent releases.

On Windows, pid is guaranteed to be valid only for the duration of the AppLaunchContext.launched signal emission; after the signal is emitted, GLib will call GLib.spawn_close_pid. If you need to keep the GLib.Pid after the signal has been emitted, then you can duplicate pid using DuplicateHandle().