public void setDefaultSelectedIndicatorSize(float width,float height,Unit unit){
        if(mUserSetSelectedIndicatorResId == 0){
            float w = width;
            float h = height;
            if(unit == Unit.DP){
                w = pxFromDp(width);
                h = pxFromDp(height);
            }
            mSelectedGradientDrawable.setSize((int) w, (int) h);
            resetDrawable();
        }
    }
if you are using the default indicator , this method will help you to set the selected status and
the unselected status color.
@param selectedColor
@param unselectedColor
library/src/main/java/com/daimajia/slider/library/Indicators/PagerIndicator.java