HarmonyOS @Track使用问题

@Track没有深度观测的功能，所以可能会出现数据更改但是UI未更改的情况，建议使用@ObservedV2装饰器和@Trace装饰器，详情请参考：

https://developer.huawei.com/consumer/cn/doc/harmonyos-guides-V5/arkts-new-observedv2-and-trace-V5

以下是参考demo：

@Entry
@Component
export struct Index {
  private arr: number[] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
  viewModel: ViewModel = new ViewModel();

  build() {
    Column() {
      List({ space: 20, initialIndex: 0 }) {
        ForEach(this.arr, (item: number) => {
          ListItem() {
            Text('' + item)
              .width('100%')
              .height(100)
              .fontSize(16)
              .textAlign(TextAlign.Center)
              .borderRadius(10)
              .backgroundColor(0xFFFFFF)
          }
        }, (item: string) => item)
        ListItem() {
          Column() {
            Row() {
              Column() {
                Text(this.viewModel.isClick ? this.viewModel.text1 : this.viewModel.text)
                  .fontSize(30)
                Button(this.viewModel.buttonText)
                  .fontSize(30)
                  .onClick(() => {
                    this.viewModel.onClick();
                  })
              }.justifyContent(FlexAlign.Center)
            }
          }
        }
      }
      .listDirection(Axis.Vertical) // 排列方向
      .scrollBar(BarState.Off)
      .friction(0.6)
      .divider({
        strokeWidth: 2,
        color: 0xFFFFFF,
        startMargin: 20,
        endMargin: 20
      }) // 每行之间的分界线
      .edgeEffect(EdgeEffect.Spring) // 边缘效果设置为Spring
      .width('90%')
    }
    .width('100%')
    .height('100%')
    .backgroundColor(0xDCDCDC)
    .padding({ top: 5 })
  }
}
@ObservedV2
export class ViewModel {
 
  @Trace isClick: boolean = false;
  @Trace text: string = "hello world!";
  @Trace text1: string = "hello world 999";
  @Trace buttonText: string = "点击";
  @Trace callback: Callback = {
    resolve: () => {
      this.isClick = true;
    }
  }

  public onClick() {
    // Manager.getInstance().setCallback(this.callback);
    Manager.getInstance().setCallback({
      resolve: () => {
        this.isClick = true;
      }
    })
    Manager.getInstance().onClick();
  }
}

export class Manager {
  private static instance: Manager;
  private callback?: Callback;

  public setCallback(callback?: Callback) {
    this.callback = callback;
  }

  public static getInstance() {
    if (!Manager.instance) {
      Manager.instance = new Manager();
    }
    return Manager.instance;
  }

  public onClick(): Promise<string> {
    return new Promise((resolve) => {
      setTimeout(() => {
        this.callback?.resolve();
        resolve("");
      }, 2 * 1000);
    });
  }
}

export interface Callback {
  resolve: () => void;
}
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