HarmonyOS Watch没有回调

可以监听到改变的：

@Observed
class ClassA {
  public c: number = 0;

  constructor(c: number) {
    this.c = c;
  }
}

@Component
struct ObjectLinkChild {
  @ObjectLink @Watch('onCountUpdated') testNum: ClassA;
  onCountUpdated(propName: string) {
    console.warn('---','propName'+propName)
  }

  build() {
    Text(`ObjectLinkChild testNum ${this.testNum.c}`)
      .onClick(() => {
        // 可以对ObjectLink装饰对象的属性赋值
        this.testNum.c = 47;
      })
  }
}

@Entry
@Component
struct Parent {
  @State testNum: ClassA[] = [new ClassA(1)];

  build() {
    Column() {
      Text(`Parent testNum ${this.testNum[0].c}`)
        .onClick(() => {
          this.testNum[0].c += 1;
        })

      ObjectLinkChild({ testNum: this.testNum[0] })
    }
  }
}