Access windows for notebook in Tkinter - authentication

Question

I have been trying to create an open windows which asks you for username and password before opening a notebook in Tkinter, I have both, but I don't know how to put them together. In other words, what I want is to open a notebook once the username and password requested are correct.
Thank you very much in advance!
What I have done so far is as follows:
import Tkinter
from Tkinter import *
import ttk
from ttk import * #Combobox Definition
import tkMessageBox #for Welcome Message
import Tkinter as tk # For Main Frame Definition
from Tkinter import Tk, Text, BOTH, W, N, E, S
from ttk import Frame, Button, Label, Style
root = Tk()
root.title("Model A")
root.minsize(400, 220)
root.maxsize(410, 240)
# start of Notebook (multiple tabs)
notebook = ttk.Notebook(root)
notebook.pack(fill='both', expand='yes')
notebook.pressed_index = None
# create a child frame for each page
frameOne = Tkinter.Frame(notebook, bg='white',width=560, height=100)
frameOne.pack(fill='both', expand=True)
# create the pages
notebook.add(frameOne, text='Simple calculation')
#Login Starts
failure_max = 8
passwords = [('name','password')]
def make_entry(parent, caption, width=None, **options):
tk.Label(parent, text=caption).pack(side=tk.TOP)
entry = tk.Entry(parent, **options)
if width:
entry.config(width=width)
entry.pack(side=tk.TOP, padx=10, fill=tk.BOTH)
return entry
def enter(event):
check_password()
def check_password(failures=[]):
if (user.get(), password.get()) in passwords:
root.destroy()
return
failures.append(1)
if sum(failures) >= failure_max:
root.destroy()
raise SystemExit('Unauthorized login attempt')
else:
root.title('Try again. Attempt %i/%i' % (sum(failures)+1, failure_max))
parent = Tkinter.Frame(notebook, padx=10, pady=18, bg='white')
parent.pack(fill=tk.BOTH, expand=True)
user = make_entry(parent, "User name:", 16, show='')
password = make_entry(parent, "Password:", 16, show="*")
b = tk.Button(parent,borderwidth=4,text="Login",width=10,pady=8,command=check_password)
b.pack(side=Tkinter.BOTTOM)
password.bind('<Return>', enter)
#Close Application Button
def quit(root):
root.destroy()
tk.Button(root, text="Close Application", command=lambda root=root:quit(root)).pack()
#Calculation Starts
def defocus(event):
event.widget.master.focus_set()
def multiply(*args):
try:
product.set(round(float(Num_One.get())*float(Num_Two.get())))
except ValueError:
pass
Num_One = StringVar()
Num_Two = StringVar()
product = DoubleVar()
ttk.Label(frameOne, text="Select First Number:").grid(column =3, row = 0)
NumOne_Select = Combobox(frameOne, values=("1", "2", "3","4", "5"),textvariable=Num_One)
NumOne_Select.grid(column=4, row=0, columnspan="5", sticky="nswe")
Num_One.trace("w", multiply)
ttk.Label(frameOne, text="Select Second Number:").grid(column =3, row = 6 )
NumTwo_Select = Combobox(frameOne, values=("1", "2", "3","4", "5"),textvariable=Num_Two)
NumTwo_Select.grid(column=4, row=6, columnspan="5", sticky="nswe")
Num_Two.trace("w", multiply)
ttk.Label(frameOne, text = "Product:").grid(column = 3, row = 8)
ttk.Label(frameOne, textvariable=product).grid(column = 4, row = 8)
user.focus_set()
parent.mainloop()
root.mainloop()

Answer 1

You have several things going wrong in your code:
you're calling mainloop twice; you should only ever call it once.
you shouldn't pack or grid widgets inside the notebook. You are packing a widget and then using notebook.add; omit the pack.
you are calling destroy on the root window if the password is good. This causes your application to exit. Don't call destroy.
Normally the way this is done is that the notebook is a child of the root window, and the username/password dialog is an instance of Toplevel. You can hide the root window and pop up the dialog, and then if the user logs in, you can destroy the dialog and un-hide the main window.