I rotate the FAB in such a simple way:
fab.startAnimation(AnimationUtils.loadAnimation(this, R.anim.rotate));
rotate.xml:
public void rotateFabForward() {
ViewCompat.animate(fab)
.rotation(135.0F)
.withLayer()
.setDuration(300L)
.setInterpolator(new OvershootInterpolator(10.0F))
.start();
}
public void rotateFabBackward() {
ViewCompat.animate(fab)
.rotation(0.0F)
.withLayer()
.setDuration(300L)
.setInterpolator(new OvershootInterpolator(10.0F))
.start();
}