code: private Drawable createBackgroundDrawable(@ColorInt final int color) {
          OvalShape shape = new OvalShape();
          ShapeDrawable drawable = new ShapeDrawable(shape);
          drawable.getPaint().setColor(color);
          return drawable;
      }
docs: Creates and returns a drawable with a specific color, which can be used as the floating
  action button's background.
  
  @param color
  The color of the background as an {@link Integer} value
  @return The drawable, which has been created, as an instance of the class {@link Drawable}