code: public function index(Request $request)
      {
          $this->site_title = '菜单管理';
          $menu_model = MenuLogic::model();
          
          // 上级
          $menu_pid = $request->param('menu_pid', 0);
          $this->assign('menu_pid', $menu_pid);
          
          $map = [
              'menu_pid' => $menu_pid
          ];
          
          // 分组列表
          $group_list = $menu_model->field('id, menu_group')
              ->where($map)
              ->group('menu_group')
              ->order('menu_sort asc')
              ->select();
          $this->assign('group_list', $group_list);
          
          // 分组
          $group_name = $request->param('group', '');
          if (! empty($group_name)) {
              $map['menu_group'] = $group_name;
          }
          $this->assign('group', $group_name);
          
          // 列表
          $list = $menu_model->where($map)
              ->order('menu_sort asc')
              ->select();
          $this->assign('list', $list);
          
          return $this->fetch();
      }
docs: 菜单列表
  
  @param Request $request
  @return string