Run your application

Make the new object app and call the method run to run the application:

let app = new HelloWorld();
app.application.run(ARGV);

Save the script as helloworld.js, run chmod +x helloworld.js to mark it executable, and run it with ./helloworld.js.

Screenshot of a basic window.

This window is generated from the Glade file and linked to Gtk events. You now have a fully functional Gtk application!