Code a timer in a python GUI in TKinter

Question

I need to code a program with GUI in python (I'm thinking of using TKinter, 'cause it's easy, but I'm open to suggestions).

My major problem is that I don't know how to code a timer (like a clock... like 00:00:00,00 hh:mm:ss,00 ) I need it to update it self (that's what I don't know how to do)

Answer 1

How about wxPython?

There is built-in classes called wx.Timer and wx.TaskBarIcon for that

Answer 2

The key is using the after() method of widgets.

See http://www.pythonware.com/library/tkinter/introduction/x9507-alarm-handlers-and-other.htm

Answer 3

Tkinter root windows have a method called "after" which can be used to schedule a function to be called after a given period of time. If that function itself calls after, you've setup up an automatically recurring event.

Here is a working example:

import Tkinter
import time

class App():
    def __init__(self):
        self.root = Tkinter.Tk()
        self.label = Tkinter.Label(text="")
        self.label.pack()
        self.update_clock()
        self.root.mainloop()

    def update_clock(self):
        now = time.strftime("%H:%M:%S")
        self.label.configure(text=now)
        self.root.after(1000, self.update_clock)

app=App()

Bear in mind that after doesn't guarantee the function will run exactly on time. It only schedules the job to be run after a given amount of time. It the app is busy there may be a delay before it is called since Tkinter is single-threaded. The delay is typically measured in microseconds.