HarmonyOS lazyforeach 配合 ListItemGroup场景该怎么写

class GlobalThis { 
  static scroller:Scroller 
} 
 
@Entry 
@Component 
struct Index1 { 
  data: DataSrc2 = new DataSrc2() 
 
  @Builder 
  itemHead(text: string) { 
    Text(text) 
      .fontSize(20) 
      .backgroundColor(0xAABBCC) 
      .width('100%') 
      .padding(10) 
  } 
 
  aboutToAppear() { 
    for (let i = 0; i < 10000; i++) { 
      let data_1 = new DataSrc1() 
      for (let j = 0; j < 12; j++) { 
        data_1.Data.push(`测试数据测试数据测试数据: ${i} - ${j}`) 
      } 
      this.data.Data.push(data_1) 
    } 
    console.log("111") 
  } 
 
  build() { 
    Stack() { 
      List() { 
        LazyForEach(this.data, (item: DataSrc1, index: number)=>{ 
          ListItemGroup({header: this.itemHead(index.toString())}){ 
            LazyForEach(item, (ii: string, index: number)=>{ 
              ListItem() { 
                Inner({str: ii}) 
              } 
            }) 
          } 
          .width('100%') 
          .height('60vp') 
        }) 
      } 
    } 
    .width('100%') 
    .height('100%') 
  } 
} 
 
@Reusable 
@Component 
struct Inner { 
  @State str: string = '' 
  aboutToReuse(param: ESObject) { 
    this.str = param.str 
  } 
  build() { 
    Text(this.str) 
  } 
} 
 
class DataSrc1 implements IDataSource { 
  listeners: DataChangeListener[] = []; 
  Data: string[] = []; 
 
  public totalCount(): number { 
    return this.Data.length; 
  } 
 
  public getData(index: number): string { 
    return this.Data[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.onData