public void setInsets(int width, int height) {
            final float minEdge = (float) Math.min(width, height);
            float insets;
            if (mRingCenterRadius <= 0 || minEdge < 0) {
                insets = (float) Math.ceil(mStrokeWidth / 2.0f);
            } else {
                insets = (float) (minEdge / 2.0f - mRingCenterRadius);
            }
            mStrokeInset = insets;
        }
@param strokeWidth Set the stroke width of the progress spinner in pixels.
ptr-lib/src/in/srain/cube/views/ptr/header/MaterialProgressDrawable.java