Problem with Tab Bar Controller

I followed the Firebase authentication Login from CWC on YouTube and he has you go to a view controller after logging in. I can not figure out how to switch that to a tab bar controller. For example, I want the user to login or auto login and then see the tab bar controller screen. I can not get this to work can someone help?

Do you have a CWC+ account?

There is a tutorial series that covers using Firebase in a number of Apps and the very issue you are dealing with is covered in the Photo App.

Here is a few screen shots of the course curriculum.

Lesson 6 in the Photo App is where saving the user state facilitates enabling you to close the App and, assuming that you have not logged out, the next time you open the APP you are effectively resuming as logged in.