How to enable threading with tkinter? - python-3.x

Question

When I want to build a program like a clock on Python3,there is a problem about threading & tkinter.
my_code :
#!/usr/bin/python3
#-*-coding:utf-8-*-
import tkinter as tk,time,threading,queue
def update_time(in_q):
while True:
in_q.put(time.strftime('%Y-%m-%d %H:%M:%S',time.localtime()))
class App_gui:
def __init__(self,parent):
self.top_frame = tk.Frame(parent)
self.clock = tk.Label(self.top_frame)
self.clock.pack()
self.top_frame.pack()
self.begin_thread()
def begin_thread(self):
self.clock_q = queue.Queue()
self.clock_thread = threading.Thread(target=update_time(self.clock_q))
self.clock_thread.start()
self.listen()
def listen(self):
gate_time = self.clock_q.get()
self.clock.config(text=gate_time)
self.clock.after(200,self.listen)
if __name__ == '__main__':
root = tk.Tk()
my_app = App_gui(root)
root.mainloop()
when I run this code,there's nothing happen.

Answer 1

Well threading is not all that difficult however in this case threading is overkill for a simple time loop.
We can use after() to manage a label for time without having to use threading.
import tkinter as tk
from time import strftime
class AppGUI(tk.Tk):
def __init__(self):
super().__init__()
self.time_label = tk.Label(self)
self.time_label.pack()
self.track_time()
def track_time(self):
self.time_label.config(text="{}".format(strftime('%Y-%m-%d %H:%M:%S')))
self.time_label.after(1000, self.track_time)
if __name__ == '__main__':
AppGUI().mainloop()

Answer 2

solved
#!/usr/bin/env python3
#-*-coding:utf-8-*-
import threading,time,tkinter as tk
def clock_task():
global clock_time
while True:
clock_time = time.strftime('%Y-%m-%d %H:%M:%S', time.localtime())
time_label.config(text=clock_time)
time.sleep(1)
clock_t = threading.Thread(target=clock_task)
clock_t.setDaemon(True)
root = tk.Tk()
time_label = tk.Label(root)
time_label.pack()
# start thread before mainloop
clock_t.start()
root.mainloop()