Hi all,

An app user has to login before navigating to the any screen. In our app user will enter username and password for login, so we need two textfield and a button two submit. so lets start and follow these steps.

1) First step is to create a non resizable window 600X400 :-

#!/usr/bin/python

import sys
if sys.version_info < (3, 0):
    # Python 2
    import Tkinter as tk
else:
    # Python 3
    import tkinter as tk

root = tk.Tk()
root.title("Mac Application")
root.resizable(width=False, height=False)
root.geometry('600x400')
tk.mainloop()

2) Now create user interface for app : We added two labels , textfield and a button , to create UI we used tkinter library of python.

#!/usr/bin/python

import sys
if sys.version_info < (3, 0):
    # Python 2
    import Tkinter as tk
else:
    # Python 3
    import tkinter as tk

username = "Jagan"
password = "123456"

class Login:

   def __init__(self, name, password):
      self.name = name
      self.password = password
      lbl1 = tk.Label( root, text="Username :").pack()
      self.e1 = tk.Entry(root, bd =5)
      self.e1.pack()
      lbl2 = tk.Label( root, text="Password :").pack()
      self.e2 = tk.Entry(root,show="*", bd =5)
      self.e2.pack()
      btn = tk.Button(root, text="Login",command=self.loginAction).pack()
      self.lbl = tk.Label( root, text="")
      self.lbl.pack()

root = tk.Tk()
root.title("Mac Application")
root.resizable(width=False, height=False)
root.geometry('600x400')

obj = Login(username, password)
tk.mainloop()

3) Now add action to button and show the status of user action below :-

#!/usr/bin/python

import sys
if sys.version_info < (3, 0):
    # Python 2
    import Tkinter as tk
else:
    # Python 3
    import tkinter as tk

username = "Jagan"
password = "123456"

class Login:

   def __init__(self, name, password):
      self.name = name
      self.password = password
      lbl1 = tk.Label( root, text="Username :").pack()
      self.e1 = tk.Entry(root, bd =5)
      self.e1.pack()
      lbl2 = tk.Label( root, text="Password :").pack()
      self.e2 = tk.Entry(root,show="*", bd =5)
      self.e2.pack()
      btn = tk.Button(root, text="Login",command=self.loginAction).pack()
      self.lbl = tk.Label( root, text="")
      self.lbl.pack()

   def loginAction(self):

   	  if self.name == self.e1.get() and self.password == self.e2.get():
   	  	self.lbl.config(text='Succesfully Logged In  !!')
   	  else:
   	  	self.lbl.config(text='Username or password is incorrect')


root = tk.Tk()
root.title("Mac Application")
root.resizable(width=False, height=False)
root.geometry('600x400')

obj = Login(username, password)
tk.mainloop()
 	 

Now you can run this app from your command line and use Jagan as username and 123456 as password to login.