Digital clock with Python Tkinter

Question

While learning about python tkinter, I decided to make a digital clock:

from datetime import datetime
import tkinter as tk
from threading import Thread
import time


class clock():
     def __init__(self):
          self.display = tk.Tk()
     def start(self):
          def get():
               self.display.geometry("215x62")
               self.display.title("Clock")
               while True:
                    try:
                         now = datetime.now()
                         current_time = now.strftime("%H:%M %p") 
                         lbl = tk.Label(self.display, text=str(current_time),
                         background = 'black', font = ("Helvetica", 37),
                         foreground = 'red')
                         lbl.place(x=0, y=0)
                         time.sleep(0.1)
                    except:
                         break
          receive_thread = Thread(target=get)
          receive_thread.start()
          self.display.mainloop()
clock = clock()
clock.start()

Is there any way to make this clock better?

Any comments, answers, or steps in the right direction would be appreciated.

Answer 1

To start, it's crucial that you stop creating a brand new label ten times a second. Just modify the existing one. Also, this is so simple that a class is not called for. Move as much as possible away from your thread, into your setup routine. Finally, your use of %H is likely incorrect given that you also include %p; you probably want %I for a 12-hour clock.

This all suggests:

from datetime import datetime
import tkinter as tk
from threading import Thread
from time import sleep


def main():
    display = tk.Tk()
    display.geometry('215x62')
    display.title('Clock')

    lbl = tk.Label(
        display,
        background='black',
        font=('Helvetica', 37),
        foreground='red',
    )
    lbl.place(x=0, y=0)

    def get():
        while True:
            now = datetime.now()
            lbl.config(text=now.strftime('%I:%M %p'))
            sleep(0.1)

    receive_thread = Thread(target=get)
    receive_thread.start()
    display.mainloop()


if __name__ == '__main__':
    main()

Ten times a second is overkill, and you can safely make this much sleepier. Do not make a thread at all; use an after() timer, and calculate when exactly the clock should tick:

from datetime import datetime
import tkinter as tk
from time import time


def main() -> None:
    display = tk.Tk()
    display.geometry('215x62')
    display.title('Clock')

    lbl = tk.Label(
        display,
        background='black',
        font=('Helvetica', 37),
        foreground='red',
    )
    lbl.place(x=0, y=0)

    def tick() -> None:
        now = datetime.now()
        lbl.config(text=now.strftime('%I:%M %p'))

        until_next = round(
            1000 * (60 - time()%60)
        )
        display.after(ms=until_next, func=tick)

    tick()
    display.mainloop()


if __name__ == '__main__':
    main()