HarmonyOS 鸿蒙Next List组件 利用LazyForEach 后不能用scroller.scrollto 去跳转

使用 LazyForEach 时，scrollTo 是生效的，

// Basic implementation of IDataSource to handle data listener

class BasicDataSource implements IDataSource {

  private listeners: DataChangeListener[] = [];

  private originDataArray: string[] = [];

  public totalCount(): number {
    return 0;
  }

  public getData(index: number): string {
    return this.originDataArray[index];
  }

  // 该方法为框架侧调用，为LazyForEach组件向其数据源处添加listener监听
  registerDataChangeListener(listener: DataChangeListener): void {
    if (this.listeners.indexOf(listener) < 0) {
      console.info('add listener');
      this.listeners.push(listener);
    }
  }

  // 该方法为框架侧调用，为对应的LazyForEach组件在数据源处去除listener监听
  unregisterDataChangeListener(listener: DataChangeListener): void {
    const pos = this.listeners.indexOf(listener);
    if (pos >= 0) {
      console.info('remove listener');
      this.listeners.splice(pos, 1);
    }
  }

  // 通知LazyForEach组件需要重载所有子组件
  notifyDataReload(): void {
    this.listeners.forEach(listener => {
      listener.onDataReloaded();
    })
  }

  // 通知LazyForEach组件需要在index对应索引处添加子组件
  notifyDataAdd(index: number): void {
    this.listeners.forEach(listener => {
      listener.onDataAdd(index);
    })
  }

  // 通知LazyForEach组件在index对应索引处数据有变化，需要重建该子组件
  notifyDataChange(index: number): void {
    this.listeners.forEach(listener => {
      listener.onDataChange(index);
    })
  }

  // 通知LazyForEach组件需要在index对应索引处删除该子组件
  notifyDataDelete(index: number): void {
    this.listeners.forEach(listener => {
      listener.onDataDelete(index);
    })
  }

  // 通知LazyForEach组件将from索引和to索引处的子组件进行交换
  notifyDataMove(from: number, to: number): void {
    this.listeners.forEach(listener => {
      listener.onDataMove(from, to);
    })
  }
}

class MyDataSource extends BasicDataSource {

  private dataArray: string[] = [];

  public totalCount(): number {
    return this.dataArray.length;
  }

  public getData(index: number): string {
    return this.dataArray[index];
  }

  public addData(index: number, data: string): void {
    this.dataArray.splice(index, 0, data);
    this.notifyDataAdd(index);
  }

  public pushData(data: string): void {
    this.dataArray.push(data);
    this.notifyDataAdd(this.dataArray.length - 1);
  }
}

@Entry
@Component
struct MyComponent {

  private data: MyDataSource = new MyDataSource();

  private scroller: ListScroller = new ListScroller();

  aboutToAppear() {
    for (let i = 0; i <= 30; i++) {
      this.data.pushData(`Hello ${i}`)
    }
  }

  build() {
    Column() {
      List({ space: 3, initialIndex: 4, scroller: this.scroller }) {
        LazyForEach(this.data, (item: string) => {
          ListItem() {
            Row() {
              Text(item).fontSize(50)
                .onAppear(() => {
                  console.info("appear:" + item)
                })
            }.margin({ left: 10, right: 10 })
          }
        }, (item: string) => item)
      }.cachedCount(5).height('70%')

      Divider().padding(8)

      Button('scroll to').onClick(() => {
        this.scroller.scrollTo({xOffset: 0, yOffset: 310})
      })
    }
  }
}

当数据源的数组项为对象数据类型，并且只修改某个数组项的属性值时，由于数据源为复杂数据类型，ArkUI框架无法监听到@State装饰器修饰的数据源数组项的属性变化，从而无法触发ForEach的重新渲染。

要实现ForEach重新渲染，需要结合@Observed和@ObjectLink装饰器使用

可以先看下：链接