python - How to run a function in the background of tkinter -

i new gui programming , want write python program tkinter. want run simple function in background can influenced through gui.

the function counts 0 infinity until button pressed. @ least want do. have no idea how can run function in background, because mainloop() of tkinter has control time. , if start function in endless loop, mainloop() cannot executed , gui dead.

i return control mainloop() after each cycle, how can control mainloop() runapp-function without user-triggered event?

here sample code kills gui:

from tkinter import *  class app:     def __init__(self, master):          frame = frame(master)         frame.pack()          self.button = button(frame, text="start", command=self.runapp)         self.button.pack(side=left)          self.hi_there = button(frame, text="restart", command=self.restart)         self.hi_there.pack(side=left)          self.runapp()      def restart(self):         print "now restarting..."      def runapp(self):         counter = 0         while (1):             counter =+ 1             time.sleep(0.1) 

you find answer in other question tkinter locks python when icon loaded , tk.mainloop in thread.

in nutshell, need have 2 threads, 1 tkinter , 1 background task.