Refer to 2nd answer of http://stackoverflow.com/questions/27213381/how-to-create-circular-progressbar-in-android
also one comment
Just one clarification for those who may encounter the same problem that I had: in ObjectAnimator.ofInt(yourId, "progress", 1, 500); you have to substitute "yourId" with your view, not the id of your view. So "findViewById(R.id.yourId)", not only "R.id.yourId". Hope it may help!
other good lib
https://github.com/dmytrodanylyk/circular-progress-button
https://github.com/dmytrodanylyk/circular-progress-button/wiki/User-Guide
https://github.com/JorgeCastilloPrz/FABProgressCircle
explanation of drawable