public class App : Object {

    private Gtk.Window window_main;
    private Gtk.Button button;
    private Gtk.MenuBar menubar;
    private Gtk.MenuItem menubar_item;
    private Gtk.Menu menu;
    private Gtk.MenuItem menuitem_button;

    public App(string datadir) {
        this.create_widgets();
        this.pack_widgets();
        this.connect_signals();

        this.window_main.show_all();

    }

    /* Private Functions */

    private void create_widgets() {
        this.window_main = new Gtk.Window();
        this.window_main.set_default_size(200, 24);

        this.button = new Gtk.Button.with_label("Heya cousin!");
        this.menubar = new Gtk.MenuBar();
        this.menubar_item = new Gtk.MenuItem.with_label("Hiya");
        this.menu = new Gtk.Menu();
        this.menuitem_button = new Gtk.MenuItem();
    }

    private void pack_widgets() {
        this.menuitem_button.add(this.button);
        this.menu.append(this.menuitem_button);
        this.menubar_item.set_submenu(this.menu);
        this.menubar.append(this.menubar_item);

        this.window_main.add(this.menubar);
    }

    private void connect_signals() {
        this.menuitem_button.button_release_event.connect(
            this.on_menuitem_button_button_release_event);
        this.menuitem_button.button_press_event.connect(
            this.on_menuitem_button_button_press_event);

        this.window_main.delete_event.connect(this.on_window_main_delete_event);
    }

    /* Callbacks */
    private bool on_window_main_delete_event(Gdk.EventAny event) {
        this.quit();
        return false;
    }

    private bool on_menuitem_button_button_press_event(Gdk.EventButton event) {
        this.button.button_press_event(event);
        return false;
    }


    private bool on_menuitem_button_button_release_event(Gdk.EventButton event) {
        this.button.button_release_event(event);
        return true;
    }

    /* Public Functions */
    public void quit() {
        Gtk.main_quit();
    }
}