HarmonyOS 鸿蒙Next 列表子元素变化，ui不渲染变化

@Observed
class FansModel {
  userId: string;
  nickName: string;
  avatar: string;
  following: number;

  constructor(userId: string, nickName: string, avatar: string, following: number) {
    this.userId = userId;
    this.nickName = nickName
    this.avatar = avatar
    this.following = following
  }
}


@Entry
@Component
struct Fans {
  @State hasFollow: boolean = false
  @State currentPage: number = 1
  @State pageSize: number = 20
  @State fansList: FansModel[] = [
    new FansModel(‘123’,‘chongxin’,‘123123’,1)
  ]

  build() {
    Column() {
      DetailNavigationTitle({ title: ‘粉丝’ })
      List() {
        ForEach(this.fansList, (item: FansModel) => {
          ListItem() {
            listView({ fans: item})
          }
        }, (item: FansModel) => item.userId)
      }
      // .onAppear(()=>{
      //   this.loadData()
      // })
    }
  }

  aboutToAppear() {
    this.loadData()
    // this.fansList.push(new FansModel(‘456’,‘123’,‘123123’,1))
  }

  loadData() {
    const data: BasePaginationRequest = {
      currentPage: 1,
      pageSize: this.pageSize
    }
    fansViewModel.queryFansList(data, (result) => {
      console.log(‘result,’, JsonUtils.stringify(result.content))
      this.fansList.push(…result.content)
      console.log(‘fansList,’, JsonUtils.stringify(this.fansList))
    })
  }
}

@Component
struct listView {
  @ObjectLink fans: FansModel;
  
  follow(){
    console.log(‘item.following:’, this.fans.following)
    if (this.fans.following === 1) {
      this.fans.following = 2
    } else {
      this.fans.following = 1
    }
   
    console.log(‘fans:’, JsonUtils.stringify(this.fans))
  }

  build() {
    Row() {
      UserAvatar({ avatarWidth: 50, avatarHeight: 50, avatarImage: this.fans.avatar })
      Text(this.fans.nickName)
        .fontSize(18)
        .fontWeight(FontWeight.Bold)
        .fontColor(Color.Black)
        .margin({ left: 10 })
      Blank()
      Button({ type: ButtonType.Normal, stateEffect: true }) {
        Text(this.fans.following === 1 ? ‘取消关注’ : ‘关  注’)
          .fontColor(this.fans.following == 1 ? Color.White : Color.Black)
          .fontWeight(FontWeight.Bold)
          .fontSize(14)
      }
      .width(80)
      .height(25)
      .borderRadius(20)
      .backgroundColor(Color.Red)
      .onClick(() => {
        this.follow()
        // this.s = !this.s
      })
    }
    .width(‘100%’)
    .padding(15)

  }
}

这里列表从接口获取数据后，this.fansList有值后，修改子元素状态，ui不会渲染变化，this.fans.following 发生变化不会被渲染，这是啥问题？如果fansList是不通过接口获取数据，反而子元素变化，ui会渲染