code: public static <T> void fire(final HasSlideHandlers<T> source, T newValue) {
          if (TYPE != null) {
              SlideEvent<T> event = new SlideEvent<T>(newValue);
              source.fireEvent(event);
          }
      }
docs: Fires a slide event on all registered handlers in the handler manager. If
  no such handlers exist, this method will do nothing.
  
  @param source the source of the handlers
  @param newValue the new slider value