code: public void update(TimelineEvent event, TimelineUpdater timelineUpdater) {
          int index = getIndex(event);
          if (index >= 0) {
              events.set(index, event);
  
              if (timelineUpdater != null) {
                  // update UI
                  timelineUpdater.update(event, index);
              }
          }
      }
docs: Updates a given event in the model with UI update.
  
  @param event           event to be added
  @param timelineUpdater TimelineUpdater instance to update the event in UI