HarmonyOS list组件点击后，滚动居中

参考下这个demo，使用scrollToIndex属性，参考文档：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/ts-container-scroll-V5#scrolltoindex

@Entry
@Component
struct CityList {
  private listScroller: Scroller = new Scroller();
  @State focusIndex: number = 0
  @State allListString: string[] = ["111", "222", "333", "444", "555", "666", "777", "888", "999"]

  build() {
    List({ scroller: this.listScroller }) {
      ForEach(this.allListString, (item: string, index: number) => {
        ListItem() {
          Text(item).onClick(() => {
            this.listScroller.scrollToIndex(index, true, ScrollAlign.CENTER)
          }).width(80)
            .textAlign(TextAlign.Center)
        }
      }, (item: string) => item)
    }
    .scrollBar(BarState.Off)
    .listDirection(Axis.Horizontal)
    .backgroundColor("#FFF1F3")
    .alignListItem(ListItemAlign.Center)
    .height(60)
    .margin({ top: 100 })
  }
}