code: public void validateRange(final LmlParser parser) {
          if (min >= max || stepSize > max - min || value < min || value > max || stepSize <= 0f) {
              parser.throwError(
                      "Range widget not properly constructed. Min value has to be lower than max and step size cannot be higher than the difference between min and max values. Initial value cannot be lower than min or higher than max value. Step size cannot be zero or negative.");
          }
      }
docs: MUST be called before using range's numeric values.
  
  @param parser used to throw exception if range is invalid.