new_contents: #!/usr/bin/env python
  # -*- Mode: Python; py-indent-offset: 4 -*-
  # vim: tabstop=4 shiftwidth=4 expandtab
  #
  # Copyright (C) 2010 Red Hat, Inc., John (J5) Palmieri <johnp@redhat.com>
  #
  # This library is free software; you can redistribute it and/or
  # modify it under the terms of the GNU Lesser General Public
  # License as published by the Free Software Foundation; either
  # version 2.1 of the License, or (at your option) any later version.
  #
  # This library is distributed in the hope that it will be useful,
  # but WITHOUT ANY WARRANTY; without even the implied warranty of
  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  # Lesser General Public License for more details.
  #
  # You should have received a copy of the GNU Lesser General Public
  # License along with this library; if not, write to the Free Software
  # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
  # USA
  
  title = "Menus"
  description = """There are several widgets involved in displaying menus. The GtkMenuBar widget is a menu bar, which normally appears horizontally at the top of an application, but can also be layed out vertically. The GtkMenu widget is the actual menu that pops up. Both GtkMenuBar and GtkMenu are subclasses of GtkMenuShell; a GtkMenuShell contains menu items (GtkMenuItem). Each menu item contains text and/or images and can be selected by the user.
  There are several kinds of menu item, including plain GtkMenuItem, GtkCheckMenuItem which can be checked/unchecked, GtkRadioMenuItem which is a check menu item that's in a mutually exclusive group, GtkSeparatorMenuItem which is a separator bar, GtkTearoffMenuItem which allows a GtkMenu to be torn off, and GtkImageMenuItem which can place a GtkImage or other widget next to the menu text.
  A GtkMenuItem can have a submenu, which is simply a GtkMenu to pop up when the menu item is selected. Typically, all menu items in a menu bar have submenus.
  GtkUIManager provides a higher-level interface for creating menu bars and menus; while you can construct menus manually, most people don't do that. There's a separate demo for GtkUIManager.
  """
  
  from gi.repository import Gtk
  
  class MenusApp:
      def __init__(self):
          self.window = Gtk.Window()
          self.window.set_title('Menus')
          self.window.connect('destroy', Gtk.main_quit)
  
          accel_group = Gtk.AccelGroup()
          self.window.add_accel_group(accel_group)
          self.window.set_border_width(0)
  
          box = Gtk.HBox()
          self.window.add(box)
  
          box1 = Gtk.VBox()
          box.add(box1)
  
          menubar = Gtk.MenuBar()
          box1.pack_start(menubar, False, True, 0)
  
          menu = self.create_menu(2, True)
  
          menuitem = Gtk.MenuItem(label='test\nline2')
          menuitem.set_submenu(self.create_menu(3, True))
          menubar.append(menuitem)
  
          menuitem = Gtk.MenuItem(label='foo')
          menuitem.set_submenu(self.create_menu(4, True))
          menuitem.set_right_justified(True)
          menubar.append(menuitem)
  
          box2 = Gtk.VBox(spacing=10)
          box2.set_border_width(10)
          box1.pack_start(box2, False, True, 0)
  
          button = Gtk.Button('Flip')
          button.connect('clicked', self.change_orientation, menubar)
          box2.pack_start(button, True, True, 0)
  
          button = Gtk.Button('Close')
          button.connect('clicked', lambda x: self.window.destroy())
          box2.pack_start(button, True, True, 0)
          button.set_can_default(True)
  
          self.window.show_all()
  
      def create_menu(self, depth, tearoff):
          if depth < 1:
              return None
  
          menu = Gtk.Menu()
          group = None
  
          if tearoff:
              menuitem = Gtk.TearoffMenuItem()
              menu.append(menuitem)
  
          i = 0
          j = 1
          while i < 5:
              label = 'item %2d - %d' % (depth, j)
              # we should be adding this to a group but the group API
              # isn't bindable - we need something more like the
              # Gtk.RadioAction API
              menuitem = Gtk.RadioMenuItem(label=label)
              menu.append(menuitem)
  
              if i == 3:
                  menuitem.set_sensitive(False)
  
              menuitem.set_submenu(self.create_menu(depth - 1, True))
  
              i += 1
              j += 1
  
          return menu
  
      def change_orientation(self, button, menubar):
          parent = menubar.get_parent()
          orientation = parent.get_orientation()
          parent.set_orientation(1 - orientation)
  
          if orientation == Gtk.Orientation.VERTICAL:
              menubar.props.pack_direction = Gtk.PackDirection.TTB
          else:
              menubar.props.pack_direction = Gtk.PackDirection.LTR
  
  def main(demoapp=None):
      app = MenusApp()
      Gtk.main()
  
  if __name__ == '__main__':
      main()
  
subject: add menu demo