TODO: Update for UIManager API. 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 diplayed when the user clicks their right mouse button. You can use Gtk::Menu's popup() method, but you need to provide a button identifier and the time of activation. This information is 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; }