HarmonyOS 嵌套Class状态观察问题？

Question

@Observed
Class A {
  field1?: string
  field2?: Array<ClassB>
}
@Observed
Class B {
  field3?: string
}
@Component
struct View {
  @ObjectLink a: ClassA
  build() {
    if (this.a && this.a.field2 && this.a.filed2.field3) {
      Text(this.a.filed2.field3)
    }
  }
}

怎么能观察到ClassB中field3变更后的状态？现在更新field3的值后页面不会刷新

Answer 1

参考demo

@ObservedV2
class Son {
  @Trace age: string = "100";
}
class Father {
  son: Son = new Son();
}
@Entry
@Component
struct Index {
  father: Father = new Father();
  build() {
    Column() {
      // 当点击改变age时，Text组件会刷新
      Text(`${this.father.son.age}`)
        .onClick(() => {
          this.father.son.age = "102";
        })
      TextInput({text: `${this.father.son.age}`, placeholder: "aaa"})
    }
  }
}