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Question

I would like to display the value of i, rest for 2 sec, then show the new value of i.

But with this code, it just display the very last value of i, not even the original value. Anyone can help me? Thank you

from tkinter import *
from time import sleep

root=Tk()
touracc=StringVar()
printer=Label(root, textvariable=touracc,bg="#85c17e")
touracc.set('yo')

for i in range(2):
    touracc.set(str(i))
    sleep(2)


printer.pack()
root.mainloop()

Answer 1

It is because sleep() will block tkinter from updating. Use after() instead:

from tkinter import *

root=Tk()

touracc=StringVar()
printer=Label(root, textvariable=touracc,bg="#85c17e")
printer.pack()
touracc.set('yo')

def update(n=0):
    if n < 2:    
        touracc.set(n)
        root.after(2000, update, n+1)

root.after(2000, update)
root.mainloop()