As described earlier, the menubutton widget has a menu that drops down from a button when the button is pressed. The menu is removed from the window when an item from the menu is selected or when the user clicks elsewhere in the application.
Many applications use a menubutton-type construct. The menubuttons are normally grouped across the top of the application and have names like File, Edit, Options, and Help. Figure 11.4 shows an example of several menubuttons grouped together in a frame.
 You can accomplish this same look in a window by using a menubar widget. However, the additional functionality that it provides is minimal, so we won't be covering it in this book. To get this look, create a frame widget with a relief of "ridge" and borderwidth of 2. Pack the menubuttons with -side => "left" for all but the help menu, which has -side => "right".
When you create a menubutton widget, use the parent widget to invoke the Menubutton method, which then creates a menubutton widget reference. The options you send with the Menubutton method can configure both the button that is initially displayed on the screen and the actual menu items:
$mbutton = $parent->Menubutton( ...