Closing main window from toplevel window with tkinter in python

Question

This is my first question, I am new to python and this site.

I am designing an app to interact with a database. I added a "close" button that I would like to open a new window asking "close the program?" and 2 buttons: yes and no. When you click no, the new window closes. When you click yes both windows close.

I got my code working but I am quite sure there is a better or smarter way of doing it.

To make it work I had to write "root.destroy()" in the "close_window" method but I am pretty sure there is a smarter way of getting the same result with something like "self.master.destroy()" that uses all the power of python. I show a simplified version of the code below.

Thanks in advance.

Alfonso

from tkinter import *

class Window():

    def __init__(self, main):
        self.main = main

        self.b5=Button(self.main, text="Action 1", width=12)
        self.b5.grid(row=0, column=1)

        self.b5=Button(self.main, text="Action 2", width=12)
        self.b5.grid(row=0, column=2)

        self.b6=Button(self.main, text="Close", width=12, command=self.new_window)
        self.b6.grid(row=0, column=3)

    def new_window(self):
        self.newWindow = Toplevel(self.main)
        self.app = Demo2(self.newWindow)

    def close_window(self):
        root.destroy()


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

        self.l1=Label(self.frame, text="Close the program?")
        self.l1.grid(row=0, column=0, columnspan=2)

        self.b1=Button(self.frame, text="Yes", command=self.yes_com)
        self.b1.grid(row=1, column=0)

        self.b1=Button(self.frame, text="No", command=self.no_com)
        self.b1.grid(row=1, column=1)

        self.frame.pack()

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

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


def main():
    global root
    root = Tk()
    app = Window(root)
    root.mainloop()

if __name__ == '__main__':
    main()

Pier Paolo · Accepted Answer · 2017-04-21T15:54:41.870

You could simply use the standard dialogs provided by the messagebox module.

Specifically, it provides the askyesno dialog that takes care of the opening/closing of the new window and returns True if the user clicks Yes and False if the user clicks No. Then, you could simply use an if-statement to close the window if the user says so by simply using self.main.destroy() (without the need to declare root as global).

from tkinter import *
from tkinter import messagebox

class Window():

    def __init__(self, main):
        self.main = main

        self.b5=Button(self.main, text="Action 1", width=12)
        self.b5.grid(row=0, column=1)

        self.b5=Button(self.main, text="Action 2", width=12)
        self.b5.grid(row=0, column=2)

        self.b6=Button(self.main, text="Close", width=12, command=self.close_window)
        self.b6.grid(row=0, column=3)

    def close_window(self):
        if messagebox.askyesno('Close', 'Close the program?'):
            self.main.destroy()

def main():
    root = Tk()
    app = Window(root)
    root.mainloop()

if __name__ == '__main__':
    main()

Notes

The yes/no buttons in the standard dialog are localized, meaning that they are translated into the language used by your computer settings.
If you have a look around the messagebox module, you'll see that there are other standard dialogs. IMHO in this case I would use askyescancel, which is used in the exact same way, but seems more semantic.

Thanks Pier Paolo. the messagebox module is exactly what I needed. If I may ask, why do I need `from tkinter import messagebox` if I am already importing the whole tkinter library with `from tkinter import *`? Thanks again for your help! — Alfonso, Apr 21 '17 at 23:42
@Alfonso: that's because `from my_package import *` does _not_ import everything in `my_module`, but only what that package decides to export. In this case `messagebox` is not automatically imported because the `tkinter` module does not explicitly export it, so you have to do it manually. For a more in depth explanation, have a look at [Why import * and then ttk?](http://stackoverflow.com/questions/24725920/why-import-and-then-ttk#24728212), which addresses the same question, but in that case the module is `ttk` instead of `messagebox`. — Pier Paolo, Apr 22 '17 at 09:59

Novel · Answer 2 · 2017-04-21T23:26:47.100

1

Pier Paolo has the right answer, but for the sake of science, here's the direct answer to your question:

def yes_com(self):
    self.master.master.destroy() # <this class instance>.<toplevel instance>.<Tk instance>.destroy()

Or you could simply quit python:

import sys

def yes_com(self):
    sys.exit()

edited Apr 21 '17 at 23:26

answered Apr 21 '17 at 17:01

Novel

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Using `sys.exit()` is fine; using just plain `exit()` or `quit()` depends on the installation, so you shouldn't use that in your code. The plain versions are there for use in the REPL. – Novel Apr 21 '17 at 23:21
Sorry, I made a quick assumption about your code. Edited. – Novel Apr 21 '17 at 23:25
Hi Jonathan, thanks for your suggestions. `sys.exit()` works perfectly fine and closes everything. I have a question here, I was told that was a better idea to destroy tkinter windows than to `quit()` or `exit()`. What do you think? `self.master.main.destroy()` did not work giving the following error: `self.master.main.destroy() AttributeError: 'Toplevel' object has no attribute 'main'` Any idea why? I would like to understand the way of linking both classes. Thanks again for your help! – Alfonso Apr 21 '17 at 23:46
`self.master.master.destroy()` works. Thanks for the explanatory comment. – Alfonso Apr 24 '17 at 12:01

Closing main window from toplevel window with tkinter in python

2 Answers2