Tkinter: cannnot create messagebox in a thread

Question

I'm a beginner at Tkinter. Yesterday, when I try to start a message box in a thread function, but it failed and stuck. I didn't find any useful information about this problem, so I asked here:

from tkinter import *
from threading import Thread

def func():
    messagebox.askyesno()

t = Thread(target=func)

Label(text='Hello').pack()

t.start()
mainloop()

No error. it just doesn't work. I also find that any dialog can not be created in the thread procedure.

Thanks for any help, or useful information.

Answer 1

You cannot call a tkinter widget method from any thread other than the one it was created in, and you can only ever create widgets in a single thread.