DrawableUtils.java 文件源码

private static Drawable getRippleMask(@ColorInt int color) {
    float[] outerRadii = new float[8];
    // 3 is the radius of final ripple, instead of 3 we can give required final radius
    Arrays.fill(outerRadii, 3);
    RoundRectShape r = new RoundRectShape(outerRadii, null, null);
    ShapeDrawable shapeDrawable = new ShapeDrawable(r);
    shapeDrawable.getPaint().setColor(color);
    return shapeDrawable;
}