public class MyWindow : Gtk.ApplicationWindow { internal MyWindow (MyApplication app) { Object (application: app, title: "MenuBar Example"); this.set_default_size (200, 200); } } class MyApplication: Gtk.Application { protected override void activate () { new MyWindow (this).show (); } protected override void startup () { base.startup (); /* Setup menubar. */ /* Get the UI file. */ var builder = new Gtk.Builder (); try { builder.add_from_file ("menubar_basis.ui"); /* Handle the exception. */ } catch (Error e) { error ("Unable to load file: %s", e.message); } /* Get the menubar from the builder. */ this.menubar = builder.get_object ("menubar") as MenuModel; } } /* main creates and runs the application. */ public int main (string[] args) { return new MyApplication ().run (args); }