from tkinter import Tk, Checkbutton, Labelfrom tkinter import StringVar, IntVarroot = Tk()text = StringVar()text.set('old')status = IntVar()def change(): if status.get() == 1: # if clicked  text.set('new') else:  text.set('old')cb = Checkbutton(root, variable=status, command=change)lb = Label(root, textvariable=text)cb.pack()lb.pack()root.mainloop()

from tkinter import *import timeclass StopWatch(Frame): '''實現一個秒表部件''' msec = 50 def __init__(self, parent=None, **kw):  Frame.__init__(self, parent, kw)  self._start = 0.0  self._elapsedtime = 0.0  self._running = False  self.timestr = StringVar()  self.makeWidgets()  self.flag = True def makeWidgets(self):  '''制作時間標簽'''  l = Label(self, textvariable = self.timestr)  self._setTime(self._elapsedtime)  l.pack(fill = X, expand = NO, pady = 2, padx = 2) def _update(self):  self._elapsedtime = time.time() - self._start  self._setTime(self._elapsedtime)  self._timer = self.after(self.msec, self._update) def _setTime(self, elap):  '''將時間格式改為 分：秒：百分秒'''  minutes = int(elap/60)  seconds = int(elap-minutes*60.0)  hseconds = int((elap - minutes*60.0 - seconds) *100)  self.timestr.set('%2d:%2d:%2d' %(minutes, seconds, hseconds)) def Start(self):  if not self._running:   self._start = time.time() - self._elapsedtime   self._update()   self._running = True def Stop(self):  '''停止秒表'''  if self._running:   self.after_cancel(self._timer)   self._elapsedtime = time.time() - self._start   self._setTime(self._elapsedtime)   self._running = False def Reset(self):  '''重設秒表'''  self._start = time.time()  self._elapsedtime = 0.0  self._setTime(self._elapsedtime) def stopwatch(self):  if self.flag == True:   self.pack(side = TOP)   Button(self, text = 'start', command = self.Start).pack(side = LEFT)   Button(self, text = 'stop', command = self.Stop).pack(side = LEFT)   Button(self, text = 'reset', command = self.Reset).pack(side = LEFT)   Button(self, text = 'quit', command = self.quit).pack(side = LEFT)    self.flag = Falseclass Watch(Frame): msec = 1000 def __init__(self, parent=None, **kw):   Frame.__init__(self, parent, kw)   self._running = False   self.timestr1 = StringVar()   self.timestr2 = StringVar()   self.makeWidgets()   self.flag = True def makeWidgets(self):  l1 = Label(self, textvariable = self.timestr1)  l2 = Label(self, textvariable = self.timestr2)  l1.pack()  l2.pack() def _update(self):  self._settime()  self.timer = self.after(self.msec, self._update) def _settime(self):  today1 = str(time.strftime('%Y-%m-%d', time.localtime(time.time())))  time1 = str(time.strftime('%H:%M:%S', time.localtime(time.time())))  self.timestr1.set(today1)  self.timestr2.set(time1) def start(self):  self._update()  self.pack(side = TOP)if __name__ == '__main__': def main():  root = Tk()  root.geometry('250x150')  frame1 = Frame(root)  frame1.pack(side = BOTTOM)  sw = StopWatch(root)  stpwtch = Button(frame1, text = '秒表', command = sw.stopwatch)  stpwtch.pack(side = RIGHT)  mw = Watch(root)  mywatch = Button(frame1, text = '時鐘', command = mw.start)  mywatch.pack(side = LEFT)  root.mainloop() main()