t禁止多个车窗打开

Question

每次我点击一个按钮，就会弹出一个新窗口，我只想在同一个窗口中完成所有操作，有人知道如何将所有操作保持在同一个窗口中吗？谢谢。这只是一些自由式的代码，所以你不必编辑整件事来告诉我怎么做。这是我的代码，谢谢你的帮助

from tkinter import *
import tkinter as tk
def mainscreen():
    global screen

    global hello
    screen = Tk()
    screen.geometry("1024x720")
    screen.title("WelcomeScreen")
    first = tk.Frame(screen).pack()

    Label(first,text = "welcomescreen", bg ="grey").pack()
    l = Label(first, text="HypeExtractor")
    l.pack()
    Label(text = "").pack()
    Button(text="Login",height="2",width="30",command = login).pack()
    Label(text = "").pack()
    Button(text="Register",height="2",width="30",command = register).pack()
    global hello
    hello = tk.Frame(screen).pack()

    screen.mainloop()


def login():
    #screen2 = Toplevel(screen)
    print(("hi"))
    usernames = username.get()
    print(usernames)
def register():
    global username
    global password
    global screen3
    global name
    global email

    screen3 = Toplevel(screen)
    screen3.title("Register")
    screen3.geometry("1024x720")
    username = StringVar()
    password = StringVar()
    name = StringVar()
    email = StringVar()


    Label(hello, text="Please enter details below").pack()
    Label(screen3, text = "").pack()
    Label(screen3, text="username").pack()
    usernameentry = Entry(screen3, textvariable=username)
    usernameentry.pack()
    Label(screen3, text="").pack()
    Label(screen3, text="password").pack()
    passwordnameentry = Entry(screen3, textvariable=password)
    passwordnameentry.pack()
    Label(screen3, text="name").pack()
    nameentry = Entry(screen3, textvariable=name)
    nameentry.pack()
    Label(screen3, text="").pack()
    Label(screen3, text="email").pack()
    emailentry = Entry(screen3, textvariable=email)
    emailentry.pack()
    Button(screen3, text="Register", command=details).pack()
    usernameentry.delete(0, END)
    passwordnameentry.delete(0,END)


def details():
    screen4 = Toplevel(screen)
    screen3.title("details")
    screen4.geometry("1024x720")
    userr = username.get()
    passrr = password.get()
    namerr = name.get()
    emailrr = password.get()

    Label(screen4, text=("These are you're details \nUsername: "+userr+"\nPassword: "+passrr+"\nName: "+namerr+"\nEmail: "+emailrr)).pack()
    Button(screen4, text="Confirm Registration",comman=bot).pack()
    Button(screen4, text="Edit Registration",command=register).pack()

def bot():
    print("hi")
mainscreen()