How to combine BottomAppBar + FAB with BottomNavigationView

Question

I want to use the FloatingActionButton, along with its behaviour when anchored on a BottomAppBar, on top of a BottomNavigationView.

I came up with a rat

Answer 1

I tried to do this for several days and in the end I came to make a FAB with an empty BottomAppBar, on top of which a BottomNavigationView with a transparent background was superimposed.

In my case, the code looks like this: