Python：Tkinter 由于 while 循环而停止答案

【问题标题】：Python: Tkinter stopping due to while loopPython：Tkinter 由于 while 循环而停止
【发布时间】：2015-08-28 15:57:48
【问题描述】：

我试图在我的程序中运行一个 while 循环，但是当 while 循环到位时，代码停止，并且 tkinter 窗口没有打开。我该如何解决这个问题？应该是这样代码写出两个随机数，然后当输入正确答案时，它应该重新循环。

from tkinter import *
import random

root = Tk() 

#Frames
topFrame = Frame(root) # I want an invisible container in root
topFrame.pack()
bottomFrame = Frame(root) # I want an invisible container in root
bottomFrame.pack(side=BOTTOM)
#End Of Frames

#Addition Question Maker



AnswerBox = Entry(topFrame)
AnswerBox.grid(row=0,column=4)
EqualsSign = Label(topFrame, text="=").grid(row=0,column=3)
AdditionSign = Label(topFrame, text="+").grid(row=0,column=1)

NewQuestion = True

while NewQuestion == True:
    AdditionQuestionLeftSide = random.randint(0, 10)
    AdditionQuestionRightSide = random.randint(0, 10)
    global Total
    Total = AdditionQuestionLeftSide + AdditionQuestionRightSide
    AdditionQuestionRightSide = Label(topFrame, text= AdditionQuestionRightSide).grid(row=0,column=0)
    AdditionQuestionLeftSide= Label(topFrame, text= AdditionQuestionLeftSide).grid(row=0,column=2)
    answer = None


def OutputAnswerText(event):
    global answer
    answer = AnswerBox.get()
    if Total == int(answer):
      Correct = Label(topFrame, text="Correct").grid(row=2,column=3)
      NewQuestion = True
    else:
       Correct = Label(topFrame, text="Wrong").grid(row=2,column=3)

AnswerBox.bind('<Return>', OutputAnswerText)

root.mainloop()

【问题讨论】：

标签： python loops while-loop tkinter

【解决方案1】：

我建议不要创建一个 while 循环，而是将 NewQuestion 设为一个函数。该函数最初被调用，然后如果答案正确，则再次调用该函数。这是我的函数代码，以及一个自动条目删除选项，以消除输入正确答案后退格的需要。

from tkinter import *
import random

root = Tk() 

#Frames
topFrame = Frame(root) # I want an invisible container in root
topFrame.pack()
bottomFrame = Frame(root) # I want an invisible container in root
bottomFrame.pack(side=BOTTOM)
#End Of Frames

#Addition Question Maker



AnswerBox = Entry(topFrame)
AnswerBox.grid(row=0,column=4)
EqualsSign = Label(topFrame, text="=").grid(row=0,column=3)
AdditionSign = Label(topFrame, text="+").grid(row=0,column=1)


def NewQuestion():
    AdditionQuestionLeftSide = random.randint(0, 10)
    AdditionQuestionRightSide = random.randint(0, 10)
    global Total
    Total = AdditionQuestionLeftSide + AdditionQuestionRightSide
    AdditionQuestionRightSide = Label(topFrame, text= AdditionQuestionRightSide).grid(row=0,column=0)
    AdditionQuestionLeftSide= Label(topFrame, text= AdditionQuestionLeftSide).grid(row=0,column=2)
    answer = None
    return

NewQuestion()

def OutputAnswerText(event):
    global answer
    global AnswerBox
    answer = AnswerBox.get()
    if Total == int(answer):
      Correct = Label(topFrame, text="Correct").grid(row=2,column=3)
      AnswerBox.delete(0, END)
      NewQuestion()
    else:
       Correct = Label(topFrame, text="Wrong").grid(row=2,column=3)

AnswerBox.bind('<Return>', OutputAnswerText)

root.mainloop()

【讨论】：

【解决方案2】：

你有一个无限循环：

while NewQuestion == True:

NewQuestion 没有任何地方可以变为假（并且循环中没有中断）。所以循环是无限的。

还有：

EqualsSign = Label(topFrame, text="=").grid(row=0,column=3)

不起作用，因为grid 返回None。如果要保留对小部件的引用，则必须使用两行版本，例如：

AnswerBox = Entry(topFrame)
AnswerBox.grid(row=0,column=4)

【讨论】：