How would I implement a swipe-based circular control like this?

Question

I am working on an Android application, and I have a TextView where I display a price (for example 50$).

I would like to have a circular control similar to this picture:

Answer 1

I had a friend that needed to implement something similar like what you want.

He actually used gesture detection - GestureOverlayView and MotionEvent.

By creating his custom gestures he managed to implement this.

My friend mostly referenced this site. There is a sample code there too.

Hope you find this useful!