Thank you guys! That was exactly what I was looking for!!!

Hello, I want to create simple variation of 15 puzzle http://en.wikipedia.org/wiki/Fifteen_puzzle http://upload.wikimedia.org/wikipedia/commons/thumb/9/91/15-puzzle.svg/220px-15-puzzle.svg.png I do not want to use pre-renderd images for buttons. How do I draw an square with a number inside, so that ...