如何在python中使用多个function创建一个精简的gui？

Question

I am trying to create a gui which would for example end the program once the user clicks a button, however, since the main portion of the program is located in the main() function, I cannot find a way to to end the program inside another function. This is my code:

import turtle
import random
from tkinter import *
from tkinter import messagebox


def main():
    windowScreen = Tk()
    windowScreen.title("Our cinema Application!")
    lbl = Label(windowScreen, text="Welcome to our cinema Application!",font=("Arial bold",50))
    lbl.grid(column=0,row=0)
    btn1 = Button(windowScreen, text="View Available Movie", bg="green", )
    btn1.grid(column=0,row=1)
    btn2 = Button(windowScreen, text="Purchase Tickets", bg="green", command=movie)
    btn2.grid(column=0,row=2)
    btn3 = Button(windowScreen, text="Exit the Application",  bg="red", command=action1, activebackground="white")
    btn3.grid(column=0,row=3)
    windowScreen.mainloop()
    print("Welcome to Dan & Fred's Cinema!")


def action1():
    messagebox.showinfo("Exit Application","Thank you for visiting and come again!")
    mainloop().exitonclick()
    exit()

Answer 1

Your program is almost correct, just remove mainloop().exitonclick() .

exitonclick is a function of turtle and would be used to close turle window, so it wont have any effect on tkinter window.

You can either make windowScreen a global variable (as @Tim Robert suggested) and add windowScreen.destroy() in action1 function or have a nested function to achive the same.

Using nested function, your code would look like this:

def main():
    def action1():
        messagebox.showinfo("Exit Application","Thank you for visiting and come again!")
        windowScreen.destroy()
    windowScreen = Tk()
    windowScreen.title("Our cinema Application!")
    btn3 = Button(windowScreen, text="Exit the Application",  bg="red", command=action1, activebackground="white")
    btn3.grid(column=0,row=3)
    windowScreen.mainloop()