Creation of canvas with animation of balls

Hello, and created an application for basketball coaches to indicate their plays with a background canvas of a basketball court and balls that symbolize each player.

When moving the balls they leave a marked color trail that is correct

But if I step over another ball it absorbs it and it no longer appears unless I reset with the button created correctly so that everything returns to its place.

I need help!

I didnt quite understand you... But this tutorial might help you...

Tutorial

See here:
Sprite Cannibalism: