提升包含小部件的TK框架

Question

我试图重现经典的“切换帧”示例。我正在尝试包括几个tkk小部件，并已使用.grid()而不是.pack()。切换帧效果很好，但是，我raising在tkk小部件上遇到了麻烦。import Tkinter as tkimport ttkfrom matplotlib.backends.backend_tkagg import (FigureCanvasTkAgg, NavigationToolbar2TkAgg)import matplotlib.pyplot as pltimport numpy as npclass SampleApp(tk.Tk):    def __init__(self, *args, **kwargs):        tk.Tk.__init__(self, *args, **kwargs)        container = tk.Frame(self)        container.grid()        container.grid_rowconfigure(0, weight=1)        container.grid_columnconfigure(0, weight=1)        self.frames = {}        for F in (StartPage, PageOne):            page_name = F.__name__            frame = F(parent=container, controller=self)            self.frames[page_name] = frame            frame.grid(row=0, column=0, sticky="nsew")        self.show_frame("StartPage")    def show_frame(self, page_name):        '''Show a frame for the given page name'''        frame = self.frames[page_name]        frame.tkraise()class StartPage(tk.Frame):    def __init__(self, parent, controller):        tk.Frame.__init__(self, parent)        self.controller = controller        self.window = parent        label = tk.Label(self, text="This is the start page")        label.grid(pady=10)        button1 = tk.Button(self, text="Go to Page One",                            command=lambda: controller.show_frame("PageOne"))        button1.grid()        self.create_widgets()如果运行此命令，您会发现我可以完美地从StartPage和PageOne更新Pages，但是绘图不会从Sin变为Cosin！为什么？