Trait gio::prelude::ApplicationExtManual

source ·

pub trait ApplicationExtManual {
    // Required methods
    fn run(&self) -> i32;
    fn run_with_args<S: AsRef<str>>(&self, args: &[S]) -> i32;
    fn connect_open<F: Fn(&Self, &[File], &str) + 'static>(
        &self,
        f: F
    ) -> SignalHandlerId;
}

Required Methods§

source

fn run(&self) -> i32

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 None 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).

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 signal::Application::handle-local-options signal is emitted, from which the application can inspect the values of its GOptionEntrys.

signal::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 signal::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 ApplicationFlags::HANDLES_COMMAND_LINE was specified then the remaining commandline arguments are sent to the primary instance, where a signal::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 signal::Application::activate signal. If there are one or more files, and ApplicationFlags::HANDLES_OPEN was specified then the files are opened via the signal::Application::open signal.

If you are interested in doing more complicated local handling of the commandline then you should implement your own 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 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 ApplicationExt::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 ApplicationFlags::IS_SERVICE or 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 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.