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Tkinter infinite loop watch?

I create a single StringVar, called time_display, which contains the mod line 3:14:02, and one label in the window, which should (theoretically) reflect the updates of the mentioned StringVar. However, when I call updateTimeto check the time and update it, I crashed in an infinite loop. Other adjustments that I made did not lead to an infinite loop, but without updating the clock. What am I doing wrong?

from tkinter import *
from tkinter import ttk
import time

root = Tk()
root.title("Clock")

def updateTime(var):
    hours = time.localtime().tm_hour
    if hours == 0:
        hours = 12
    minutes = time.localtime().tm_min
    if minutes < 10:
        minutes = '0' + str(minutes)
    else:
        minutes = str(minutes)
    seconds = time.localtime().tm_sec
    if seconds < 10:
        seconds = '0' + str(seconds)
    else:
        seconds = str(seconds)
    current_time = str(hours) + ':' + minutes + ':' + seconds
    var.set(current_time)
    root.after(500, updateTime(var))

time_display = StringVar()
updateTime(time_display)

ttk.Label(root, textvariable=time_display).grid(column=0, row=0)
root.mainloop()
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1 answer

On the next line, the code calls updateTimedirectly; calling recursive call.

root.after(500, updateTime(var))
#                         ^   ^

Pass the function and argument without calling, this will solve your problem.

root.after(500, updateTime, var)

Alternatively you can use lambda:

root.after(500, lambda: updateTime(var))

BTW, time.strftime, updateTime :

def updateTime(var):
    var.set(time.strftime('%H:%M:%S'))
    root.after(500, updateTime, var)
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