倒计时错误

Question

此代码会产生一个错误，我不知道为什么或者如何解决它？

File "/Users/johnz/Dropbox/PythonWorkspace/BumpersRev1/test3.py", 
    line 7, in countdown 
if self.remaining <= 0: 
AttributeError: 'int' object has no attribute 'remaining'` 

。

from tkinter import * 

# count down timer 
def countdown(self, remaining = None): 
    if remaining is not None: 
     self.remaining = remaining 
    if self.remaining <= 0: 
     pass 
    else: 
     self.remaining = self.remaining - 1 
     self.after(1000, self.countdown) 

def main(): 
# create a Tk window 
    win1 = Tk() 
    countdown(90) 
    mainloop() 

main() 

Answer 1

您正试图将一个整数传递给函数倒数。应该指出的是，self是常规的。不需要命名，但这是我们通常使用的。然而，因为这不是一个实例函数（即不是一个类的一部分），所以你没有理由继承这个对象本身。这可以完全没有自己。

import functools 
from Tkinter import * 
def countdown(remaining = None): 
    if remaining <= 0 or remaining is None: 
     pass 
    else: 
     remaining -= 1 
     # Requires a widget instance here.... 
     # Widget.after(1000, functools.partial(countdown, remaining)) 

Answer 2

你必须在after

from tkinter import * 

# count down timer 
def countdown(remaining, widget): 
    print(remaining) 

    if remaining > 0: 
     remaining = remaining - 1 
     widget.after(1000, countdown, remaining, widget) 

def main(): 
    win1 = Tk() 
    countdown(90, win1) 
    mainloop() 

main() 

发送参数如果win1将是全球性的变量，那么你不必送widget

from tkinter import * 

# count down timer 
def countdown(remaining): 
    print(remaining) 

    if remaining > 0: 
     remaining = remaining - 1 
     win1.after(1000, countdown, remaining) 


# global variables 
win1 = Tk() 
countdown(90) 
mainloop() 

BTW：例如与after ADN显示当前时间tkinter窗口中： Tkinter Text Animation?