code: protected Integer getIntFromRangeElement(String attribute) {
          Element ele = $(rangeInputElement).asElement();
          if (ele != null) {
              return ele.getPropertyInt(attribute);
          }
          return null;
      }
docs: Retrieve the Integer value from the given Attribute of the range element
  
  @param attribute The name of the attribute on the range element
  @return The Integer vaulue read from the given attribute or null