How to create a floating action button (FAB) in android, using AppCompat v21?

Question

I would like to create a floating action button (to add items to a listview), like google calendar, maintaining compatibility with pre-lollipop Android versions (before 5.0)

Answer 1

Here is one aditional free Floating Action Button library for Android It has many customizations and requires SDK version 9 and higher

Full Demo Video