只要一组中有一个元素被选中，整个组都会被选中，这个怎么解决？

getAttendPerson(item,isGroup){
      var _this = this;
      if(isGroup == 0){//来自部门的
        _this.attendPerson.forEach((item1,index) => {
          if(item.id == item1.extend1 && item1.extend2 == 0){
            _this.officeDfaultChecked.push(item1.userId);

          }
        });
//        console.log(_this.officeDfaultChecked);

        _this.officeData.push({
          office:item,
          defaultChecked:_this.officeDfaultChecked,
          defaultExpanded:[item.id]
        });
//        console.log(_this.officeDfaultChecked);



      }else if(isGroup == 1){//来自小组的数据
        _this.attendPerson.forEach((item1,index) => {
          if(item.groupId == item1.extend1 && item1.extend2 == 1){
            _this.teamDfaultChecked.push(item1.userId);
          }
        });
        _this.teamData.push({
          team:item,
          defaultChecked:_this.teamDfaultChecked,
          defaultExpanded:[item.groupId]
        });

      }
    }
  },
    mounted(){
    },
    created() {
        var _this = this;
        //设置当前活动步骤
        this.active = this.edittabActiveElstep;

        _this.questionData.list=_this.editQuestionList;

        //编辑时，获取参会的处室和人员
        if(_this.isEditOrAdd == "edit"){
            axios.post("/yangfan-server/yfDesignatedAttendEmployees/getYfDesignatedAttendEmployeesAll",qs.stringify({

                    trainId:_this.editInfo.id
                })).then((response)=>{
                debugger;
                _this.attendPerson = response.data;

            })
        }
        //获取处室(按处室选择参会人员)
        axios.post("/yangfan-server/yfOffice/getAllOffices").then((response)=>{
            var tempTeamData = response.data;
            tempTeamData.forEach((item,index) => {
                if(_this.isEditOrAdd == "edit"){
                    var isGroup = 0;
                    _this.getAttendPerson(item,isGroup);
                }else{

                    _this.officeData.push({
                        office:item,
                        defaultChecked:[],
                        defaultExpanded:[]
                    });
                }

            });
        })
        //获取分组(按分组选择参会人员)
        axios.post("/yangfan-server/yfTeam/getYfTeamAll").then((response)=>{
            debugger;
            var tempOfficeData = response.data;
            tempOfficeData.forEach((item,index) => {
                if(_this.isEditOrAdd == "edit"){
                    var isGroup = 1;
                    _this.getAttendPerson(item,isGroup);
                }else{

                    _this.teamData.push({
                        team:item,
                        defaultChecked:[],
                        defaultExpanded:[]

                    });
                }

            });
        })
    }
}