The Android Design Support Library offers the BottomNavigationView component. This view creates a navigation bar at the bottom of the screen making it easy to update the main contents and explore them in one click.
Unfortunately, this view doesn't offer the "badges" feature in the bar icons.
It's strange because many apps have implemented it, including those of Google :
In this code snippet, badges can be added to bar icons and a ViewModel maintains the state of the badges.
Post on Medium (in french) : Des badges dans la BottomNavigationView sur Android