Workshop 6/7: My final application

Below are screenshots of my application as it stands:

1. This shows the main page when you first start the application.
   
2. If I click on Log Out the following screen appears:
   
   This would seem to imply that the user has been logged out. Howver if I simply click on Book Cab
3. 
   This is the screen that display when the user selects Book Cab. Irrespective of the user being logged in or not.
4. 
   
   This is the screen I get if I try to login from the login screen without a valid user being specified.
   This actually implies to me that the session management is working correctly, but I am not getting the expected results throughout the application.