tkinter：AttributeError：'str'对象没有属性'tk'

Question

我正在使用tkinter模块为登录系统编写代码。 Python返回属性错误，我只是在学习tkinter模块。帮助将不胜感激。正在使用exec命令从另一个文件运行代码。这是我的代码：

#import modules

from tkinter import *
import os
import pygame
from Mathletics_V2 import *

# Designing window for registration

def register():
    global register_screen
    register_screen = Toplevel(main_screen)
    register_screen.title("Register")
    register_screen.geometry("300x250")

    global username
    global password
    global username_entry
    global password_entry
    username = StringVar()
    password = StringVar()

    Label(register_screen, text="Please enter details below", bg="blue").pack()
    Label(register_screen, text="").pack()
    username_lable = Label(register_screen, text="Username * ")
    username_lable.pack()
    username_entry = Entry(register_screen, textvariable=username)
    username_entry.pack()
    password_lable = Label(register_screen, text="Password * ")
    password_lable.pack()
    password_entry = Entry(register_screen, textvariable=password, show='*')
    password_entry.pack()
    Label(register_screen, text="").pack()
    Button(register_screen, text="Register", width=10, height=1, bg="blue", command = register_user).pack()



# Designing window for login 

def login():
    global login_screen
    login_screen = Toplevel(main_screen)
    login_screen.title("Login")
    login_screen.geometry("300x250")
    Label(login_screen, text="Please enter details below to login").pack()
    Label(login_screen, text="").pack()

    global username_verify
    global password_verify

    username_verify = StringVar()
    password_verify = StringVar()

    global username_login_entry
    global password_login_entry

    Label(login_screen, text="Username * ").pack()
    username_login_entry = Entry(login_screen, textvariable=username_verify)
    username_login_entry.pack()
    Label(login_screen, text="").pack()
    Label(login_screen, text="Password * ").pack()
    password_login_entry = Entry(login_screen, textvariable=password_verify, show= '*')
    password_login_entry.pack()
    Label(login_screen, text="").pack()
    Button(login_screen, text="Login", width=10, height=1, command =login_verify).pack()

# Implementing event on register button

def register_user():

    username_info = username.get()
    password_info = password.get()

    file = open(username_info, "a+")
    file.write(username_info + "
")
    file.write(password_info + "
")
    file.close()

    username_entry.delete(0, END)
    password_entry.delete(0, END)

    Label(register_screen, text="Registration Success", fg="green", font=("calibri", 11)).pack()

# Implementing event on login button 

def login_verify():
    global username1
    username1 = username_verify.get()
    password1 = password_verify.get()
    username_login_entry.delete(0, END)
    password_login_entry.delete(0, END)

    list_of_files = os.listdir()
    if username1 in list_of_files:
        file1 = open(username1, "r")
        print(username1)
        verify = file1.read().splitlines()
        if username1 == 'admin':
            tMain_Screen()
        elif password1 in verify:
            login_sucess()
        else:
            password_not_recognised()
    else:
        user_not_found()

# Designing popup for login success

def login_sucess():
    global login_success_screen
    login_success_screen = Toplevel(login_screen)
    login_success_screen.title("Success")
    login_success_screen.geometry("150x100")
    Label(login_success_screen, text="Login Success").pack()
    Button(login_success_screen, text="OK", command=delete_login_success).pack()
    game_intro()

# Designing popup for login invalid password

def password_not_recognised():
    global password_not_recog_screen
    password_not_recog_screen = Toplevel(login_screen)
    password_not_recog_screen.title("Success")
    password_not_recog_screen.geometry("150x100")
    Label(password_not_recog_screen, text="Invalid Password ").pack()
    Button(password_not_recog_screen, text="OK", command=delete_password_not_recognised).pack()

# Designing popup for user not found

def user_not_found():
    global user_not_found_screen
    user_not_found_screen = Toplevel(login_screen)
    user_not_found_screen.title("Success")
    user_not_found_screen.geometry("150x100")
    Label(user_not_found_screen, text="User Not Found").pack()
    Button(user_not_found_screen, text="OK", command=delete_user_not_found_screen).pack()

# Deleting popups

def delete_login_success():
    login_success_screen.destroy()


def delete_password_not_recognised():
    password_not_recog_screen.destroy()


def delete_user_not_found_screen():
    user_not_found_screen.destroy()


# Designing Main(first) window

def main_account_screen():
    global main_screen
    main_screen = Tk()
    main_screen.geometry("300x250")
    main_screen.title("Account Login")
    Label(text="Select Your Choice", bg="blue", width="300", height="2", font=("Calibri", 13)).pack()
    Label(text="").pack()
    Button(text="Login", height="2", width="30", command = login).pack()
    Button(text="Registration", height="2", width="30", command= register).pack()
    Button(text="Quit", height="2", width="30", command= quit).pack()

    main_screen.mainloop()
#Teacher Screen
def tStudent_Progress():
    global Student_Progress_Screen
    Student_Progress_Screen = Toplevel(Main_Screen)
    Student_Progress_Screen.title("Student Progress")
    Student_Progress_Screen.geometry("500x500")
    Label(Student_Progress_Screen,text="Student Progress").pack()
    #Use while loop to list buttons for registered students

def tgame():
    game_intro()

#def tutorial():
    #Function to Change Tutorial Links

def tMain_Screen():
    global tmain_Screen
    tmain_Screen = Toplevel(login_screen)
    tmain_Screen.geometry("300x400")
    tmain_Screen.title("Admin Interface")
    Label("tmain_screen",text="Select Your Choice", bg="blue", width="300", height="2", font=("Calibri", 13)).pack()
    Label(text="").pack()
##    Button(text="Student Progess",height="2", width=" 30", command = tStudent_Progress).pack()
##    Button(text="Game", height="2", width="30", command = tgame).pack()
##    #Button(text="Tutorial",height="2",width="30", command = ttutorial).pack()
##    Label(text="").pack()
##    Button(text="Quit",height="2", width="30",command = quit).pack()

main_account_screen()

这是我的错误：

Exception in Tkinter callback
Traceback (most recent call last):
  File "C:UsersEthanAppDataLocalProgramsPythonPython38-32lib	kinter\__init__.py", line 1883, in __call__
    return self.func(*args)
  File "<string>", line 100, in login_verify
  File "<string>", line 187, in tMain_Screen
  File "C:UsersEthanAppDataLocalProgramsPythonPython38-32lib	kinter\__init__.py", line 3143, in __init__
    Widget.__init__(self, master, 'label', cnf, kw)
  File "C:UsersEthanAppDataLocalProgramsPythonPython38-32lib	kinter\__init__.py", line 2561, in __init__
    BaseWidget._setup(self, master, cnf)
  File "C:UsersEthanAppDataLocalProgramsPythonPython38-32lib	kinter\__init__.py", line 2530, in _setup
    self.tk = master.tk
AttributeError: 'str' object has no attribute 'tk'

我正在使用空闲，非常感谢您的帮助。这让我难过。该错误仅在访问此界面的admin部分时运行。