Popup Menus

Menus are normally just added to a window, but they can also be displayed temporarily as the result of a mouse button click. For instance, a context menu might be displayed when the user clicks their right mouse button.

The UI layout for a popup menu should use the popup node. For instance:

Glib::ustring ui_info =
    "<ui>"
    "  <popup name='PopupMenu'>"
    "    <menuitem action='ContextEdit'/>"
    "    <menuitem action='ContextProcess'/>"
    "    <menuitem action='ContextRemove'/>"
    "  </popup>"
    "</ui>";

m_refUIManager->add_ui_from_string(ui_info);

To show the popup menu, use Gtk::Menu's popup() method, providing the button identifier and the time of activation, as provided by the button_press_event signal, which you will need to handle anyway. For instance:

bool ExampleWindow::on_button_press_event(GdkEventButton* event)
{
  if( (event->type == GDK_BUTTON_PRESS) &&
      (event->button == 3) )
  {
    m_Menu_Popup->popup(event->button, event->time);
    return true; //It has been handled.
  }
  else
    return false;
}