This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
The MyPanel should work as written, the box will move if the X and Y are incremented. So I would suggest inserting a print line statement in the setCurrentX, and setCurrentY to see what is happening. For example: