application: Add application menu and empty preferences() method.

            window.present ();

            window.present ();

        }

        }

        private void preferences () {

        }

        public override void startup () {

            base.startup ();

            var action = new GLib.SimpleAction ("preferences", null);

            action.activate.connect (() => preferences ());

            add_action (action);

            action = new GLib.SimpleAction ("quit", null);

            action.activate.connect (() => quit ());

            add_action (action);

            add_accelerator ("<Ctrl>Q", "app.quit", null);

            var builder = new Gtk.Builder.from_resource ("/org/gtk/exampleapp/app-menu.ui");

            var app_menu = builder.get_object ("appmenu") as GLib.MenuModel;

            set_app_menu (app_menu);

        }

    }

    }

}

}