code: void onGroupTabClicked(String id) {
          TargetDivNavWidget navGroupWidget = (TargetDivNavWidget) super.getSubgroupNavWidget(id);
          if (navGroupWidget != null) {
              super.onItemClicked(navGroupWidget.getNavGroup());
              view.showChildrenTabs(navGroupWidget);
              navGroupWidget.gotoDefaultItem();
          }
      }
docs: View callbacks