# This program demonstrates a group of Radiobutton widgets.

import Tkinter
import tkMessageBox

class MyGUI:
    def __init__(self):
        # Create the main window.
        self.main_window = Tkinter.Tk()

        # Create two frames. One for the Radiobuttons
        # and another for the regular Button widgets.
        self.top_frame = Tkinter.Frame(self.main_window)
        self.bottom_frame = Tkinter.Frame(self.main_window)
        
        # Create an IntVar object to use with
        # the Radiobuttons.
        self.radio_var = Tkinter.IntVar()
        
        # Set the intVar object to 1.
        self.radio_var.set(1)

        # Create the Radiobutton widgets in the top_frame.
        self.rb1 = Tkinter.Radiobutton(self.top_frame, \
                    text='Option 1', variable=self.radio_var, \
                    value=1)
        self.rb2 = Tkinter.Radiobutton(self.top_frame, \
                    text='Option 2', variable=self.radio_var, \
                    value=2)
        self.rb3 = Tkinter.Radiobutton(self.top_frame, \
                    text='Option 3', variable=self.radio_var, \
                    value=3)

        # Pack the Radiobuttons.
        self.rb1.pack()
        self.rb2.pack()
        self.rb3.pack()

        # Create an OK button and a Quit button.
        self.ok_button = Tkinter.Button(self.bottom_frame, \
                      text='OK', command=self.show_choice)
        self.quit_button = Tkinter.Button(self.bottom_frame, \
                      text='Quit', command=self.main_window.destroy)

        # Pack the Buttons.
        self.ok_button.pack(side='left')
        self.quit_button.pack(side='left')

        # Pack the frames.
        self.top_frame.pack()
        self.bottom_frame.pack()
        
        # Start the mainloop.
        Tkinter.mainloop()

    # The show_choice method is the callback function for the
    # OK button.
    
    def show_choice(self):
        tkMessageBox.showinfo('Selection', 'You selected option ' +\
                              str(self.radio_var.get()))
def main():
   # Create an instance of the MyGUI class.
   my_gui = MyGUI()

main()