Python

import Tkinter as tk
import RPi.GPIO as GPIO

# Warnungen ausschalten
GPIO.setwarnings(False)
#Boardmodus
GPIO.setmode(GPIO.BCM)
#setzen des GPIO 23 auf HIGH
GPIO.setup(22, GPIO.IN, pull_up_down=GPIO.PUD_UP)


nummer = 0

def update_timeText():
    if (state):
        global timer
        timer[2] += 1

        if (timer[2] >= 100):
            timer[2] = 0
            timer[1] += 1

        if (timer[1] >= 60):
            timer[0] += 1
            timer[1] = 0

        timeString = pattern.format(timer[0], timer[1], timer[2])

        timeText.configure(text=timeString)

    root.after(10, update_timeText)


def start():
    global state
    GPIO.wait_for_edge(22, GPIO.FALLING)
    state = True

def stop():
    global state
    state = False

def exist():
    root.destroy()

def zeiten():
    global timer
    global nummer
    print "Dauer: ", timer
    file = open("log.txt", "a")
    file.write("Teil" + " #" + repr(nummer) + " " + repr(timer) + '\n')
    nummer += 1
    timer = [0, 0, 0]
    timeText.configure(text='00:00:00')



state = False


root = tk.Tk()
self = root

self.overrideredirect(1)
w, h = self.winfo_screenwidth(), self.winfo_screenheight()
self.geometry("%dx%d+0+0" % (w, h))

root.wm_title('Stoppuhr')

timer = [0, 0, 0]

pattern = '{0:02d}:{1:02d}:{2:02d}'


timeText = tk.Label(root, text="00:00:00", font=("Helvetica", 150))
timeText.pack()

startButton = tk.Button(root, text='Start', command=start)
startButton.pack()

pauseButton = tk.Button(root, text='Stop', command=stop and zeiten)
pauseButton.pack()

quitButton = tk.Button(root, text='Quit', command=exist)
quitButton.pack()

update_timeText()
root.mainloop()