How do I apply an animation around a button?

Question

I have 30 sec of a song being played when the play button is being played. I want a progress bar to go around the play button as the song is being played. How would I do this? <

Answer 1

I'm assuming you want something like this:

It is a CAShapeLayer whose path is a circle. We start with a strokeEnd of 0 and animate it up to 1. You can poll the song's progress using an NSTimer at, say, 1-second intervals and calculate how much of the song has played, and set the strokeEnd to that fraction.