FloatingActionButton.java 文件源码

private CircleDrawable(Shape s) {
    super(s);
    circleInsetHorizontal = hasShadow() ? mShadowRadius + Math.abs(mShadowXOffset) : 0;
    circleInsetVertical = hasShadow() ? mShadowRadius + Math.abs(mShadowYOffset) : 0;

    if (mProgressBarEnabled) {
        circleInsetHorizontal += mProgressWidth;
        circleInsetVertical += mProgressWidth;
    }
}