How to add the middle Button in BottomBar layout android

Question

I want to add facebook messenger like oversized button in the middle of my bottombar layout but confused how to add..

Facebook Messenger

I was using

Answer 1

I just tried to make it simple, not professional type. Look here:

BottomSheetLayout file - tv.xml:

ActivityLayout - activity_main.xml

Output:

Change value and design as per your idea.

Example is just a demo and does not contain exact answer asked by OP. Its just a hard coded dummy.