python - self.bell()创建一个RecursionError

Question

我正在研究密码管理器，它分为几个类。当不满足特定条件时，我希望响铃以通知用户。在一个简单的代码版本中，我使用了很好的旧self.bell()没问题(所有代码都在一个类下-不好，因此是升级版本)。
在升级的代码中，我得到了递归错误。

我经历了我能想到的一切，没有喜悦。我似乎找不到足够接近的案例可以在各种论坛上找到。
我在Windows7上使用pycharm 2019.1.3。

主文件:

from class_createNewPassword import *
from class_searchDatabase import *
from class_updateDatabase import *


class display(Tk):
    def __init__(self, master=None):
        # main window
        Tk.__init__(self, master)
        self.title('Password Manager')

        buttonCreate = ttk.Button(self, text='Create a new password', command=createNewPassword)
        buttonCreate.grid(column=0, row=0)

        buttonSearch = ttk.Button(self, text='Search the database', command=SearchDatabase)
        buttonSearch.grid(column=1, row=2)

        buttonUpdate = ttk.Button(self, text='Update the database', command=UpdateDatabase)
        buttonUpdate.grid(column=2, row=4)


if __name__ == "__main__":
app = display()
app.mainloop()

问题所在的文件:

from tkinter import *
from tkinter import ttk
import tkinter as tk
from class_makePassword import *


class createNewPassword(Tk):
    def __init__(self):
        createWindow = tk.Toplevel()
        createWindow.title('Create a password')

        Toplevel.connection = sqlite3.connect("mdp - Copy.db")
        Toplevel.cursor = Toplevel.connection.cursor()
        self.connection = Toplevel.connection
        self.cursor = Toplevel.cursor

        #bunch of tkinter variables and stuff, and some functions not related to the issue


    def savePassword(self, condition):

        if condition:  #writes data in the DB, works well
            pass
        else:
            print("problem")
            self.bell()  #problem is here

我收到此错误消息:

Exception in Tkinter callback
Traceback (most recent call last):
File "F:\Python37-32\lib\tkinter\__init__.py", line 1705, in __call__
return self.func(*args)
File "I:\01 Programs\01 On the way\SQL\password manager with classes\class_createNewPassword.py", line 249, in savePassword
self.bell()
File "F:\Python37-32\lib\tkinter\__init__.py", line 783, in bell
self.tk.call(('bell',) + self._displayof(displayof))
File "F:\Python37-32\lib\tkinter\__init__.py", line 2101, in __getattr__
return getattr(self.tk, attr)
File "F:\Python37-32\lib\tkinter\__init__.py", line 2101, in __getattr__
return getattr(self.tk, attr)
File "F:\Python37-32\lib\tkinter\__init__.py", line 2101, in __getattr__
return getattr(self.tk, attr)
[Previous line repeated 493 more times]
RecursionError: maximum recursion depth exceeded while calling a Python object

谁能告诉我我的代码有什么问题吗？
谢谢。

Answer 1

问题的根源在于您的createNewPassword类继承自Tk，但您没有调用Tk.__init__来正确初始化该类。

我根本看不到您为什么要从Tk继承的任何原因。而是从Toplevel继承并正确初始化它:

class createNewPassword(Toplevel):
    def __init__(self):
        Toplevel.__init__(self)
        self.title('Create a password')
        ...

    def savePassword(self, condition):

        if condition:
            pass
        else:
            self.bell()