tkinter simple OO code II

tk-class2.py

#!/usr/sbin/env python

import tkinter as tk


class Demo1:
    def __init__(self, master):
        self.master = master

    def create_frame(self):
        self.frame = tk.Frame(self.master)
        self.button = tk.Button(self.frame, text="New Window ...",
                                width=25, command=self.new_window)
        self.button2 = tk.Button(self.frame, text='Close',
                                 width=25, command=self.close)
        self.button.pack()
        self.button2.pack()
        self.frame.grid()

    def new_window(self):
        # self.newWindow = tk.Toplevel(self.master)
        self.app = Demo2(self.master)
        self.close()
        self.app.create_frame()

    def close(self):
        self.frame.grid_forget()


class Demo2:
    def __init__(self, master):
        self.master = master

    def create_frame(self):
        self.frame = tk.Frame(self.master)
        self.quitButton = tk.Button(self.frame, text="Quit",
                                    width=25, command=self.close_window)
        self.quitButton.pack()
        self.backButton = tk.Button(self.frame, text="Back",
                                    width=25, command=self.back)
        self.backButton.pack()
        self.frame.grid()

    def close_window(self):
        self.master.destroy()

    def back(self):
        self.app = Demo1(self.master)
        self.close()
        self.app.create_frame()

    def close(self):
        self.frame.grid_forget()


def main():
    root = tk.Tk()
    app = Demo1(root)
    app.create_frame()
    root.title("Demo1")
    root.mainloop()

if __name__ == '__main__':
    main()