How can you make a custom keyboard in Android?

Question

I want to make a custom keyboard. I don\'t know how to do it using XML and Java. The following picture is a model of the keyboard I want to make. It only needs numbers.

Answer 1

One of the best well-documented example I found.

http://www.fampennings.nl/maarten/android/09keyboard/index.htm

KeyboardView related XML file and source code are provided.