You can hide window

root.withdraw()

# or 

root.iconify()

and show again

root.deiconify()

To disable button

b['state'] = 'disabled'

To enable button

b['state'] = 'normal'

EDIT: as @acw1668 noted in comment it needs win.protocol() to run close_second when user used closing button [X] on title bar

import tkinter as tk # PEP8: `import *` is not preferred

#--- functions ---

def close_second():
    win.destroy()

    b['state'] = 'normal'

    root.deiconify()

def open_second():
    global win

    b['state'] = 'disabled'
    #root.iconify()
    root.withdraw()

    win = tk.Toplevel()

    win_b = tk.Button(win, text="Close Second", command=close_second)
    win_b.pack()

    # run `close_second` when user used closing button [X] on title bar
    win.protocol("WM_DELETE_WINDOW", close_second)

# --- main ---

root = tk.Tk()

b = tk.Button(root, text="Open Second", command=open_second)
b.pack()

root.mainloop()

您可以使用.grab_set（）来禁用与主窗口的交互。您可以在单击某个按钮时关闭该窗口，并在单击另一个按钮时重新打开上一个窗口。

from tkinter import *

root = Tk()

def reopen():
    root.mainloop()
    w.withdraw()

def z():
    w = Toplevel()
    w.grab_set()
    bu = Button(w, text = "Click!", font = 'bold', command=reopen)
    bu.pack()
    root.withdraw()
    w.mainloop()

b = Button(root, text = "Click!", command = z)
b.pack()

root.mainloop()

欢迎来到Tkinter图书馆。
我知道你为什么要用“w”，你可以用root，它就可以工作了。

from tkinter import *
root = Tk()

def z():

    bu = Button(root, text = "Click!", font = 'bold')
    bu.pack()

b = Button(root, text = "Click!", command = z)
b.pack()

root.mainloop()

如果你在python和tkinter中遇到任何问题，请询问我。