OptionMenu小部件不过是一个便利类，它创建与菜单关联的菜单按钮。您可以通过
"menu"属性进入此菜单。唯一的技巧是知道菜单项应该做什么，这无非就是设置关联变量的值。
这是一个例子：
import Tkinter as tkclass SampleApp(tk.Tk): def __init__(self, *args, **kwargs): tk.Tk.__init__(self, *args, **kwargs) self.om_variable = tk.StringVar(self) b1 = tk.Button(self, text="Colors", width=8, command=self.use_colors) b2 = tk.Button(self, text="Sizes", width=8, command=self.use_sizes) self.om = tk.OptionMenu(self, self.om_variable, ()) self.om.configure(width=20) self.use_colors() b1.pack(side="left") b2.pack(side="left") self.om.pack(side="left", fill="x", expand=True) def _reset_option_menu(self, options, index=None): '''reset the values in the option menu if index is given, set the value of the menu to the option at the given index ''' menu = self.om["menu"] menu.delete(0, "end") for string in options: menu.add_command(label=string, command=lambda value=string: self.om_variable.set(value)) if index is not None: self.om_variable.set(options[index]) def use_colors(self): '''Switch the option menu to display colors''' self._reset_option_menu(["red","orange","green","blue"], 0) def use_sizes(self): '''Switch the option menu to display sizes''' self._reset_option_menu(["x-small", "small", "medium", "large"], 0)if __name__ == "__main__": app = SampleApp() app.mainloop()
