HarmonyOS @Observed/@ObjectLink装饰器相关问题

import { plainToClass, Type } from 'class-transformer'; 
import 'reflect-metadata'; 
import { Person, ViewA } from './ViewA'; 
 
class ResponseObj { 
  @Type(() => Person) 
  data: Person[] = []; 
} 
 
 
@Entry 
@Component 
struct TestJson { 
  @State list: Person[] = []; 
  @State message: string = 'Click me'; 
 
 
  aboutToAppear(): void { 
    let str = '{"data" : [{"number" :1,"age": 20, "testA": { "str" : "123"}},{"number" :2,"age": 21,"testA": {"str" : "456"}}]}' 
    let jsonData: ESObject = JSON.parse(str) 
    let responseObj: ResponseObj = plainToClass(ResponseObj, jsonData); 
    console.log( ${responseObj.data[0] instanceof Person}) 
    this.list = this.list.concat(responseObj.data); 
  } 
 
 
  build() { 
    Row() { 
      Column() { 
        ForEach(this.list, (item: Person, index: number) => { 
          ViewA({ index: index, testA: item.testA }) 
        }) 
      } 
      .width('100%') 
    } 
    .height('100%') 
  } 
} 
 
 
ViewA.ets 
import { Type } from 'class-transformer' 
 
 
@Observed 
export class TestA { 
  public str : string 
 
 
  constructor(str: string) { 
    this.str = str; 
  } 
} 
 
 
export class Person { 
  name: string = '' 
  age: number = 1 
 
 
  @Type(()=>TestA) 
  testA: TestA = new TestA('') 
} 
 
 
@Component 
export struct ViewA { 
  @ObjectLink testA: TestA 
  index: number = -1; 
 
 
  build() { 
    Row(){ 
      Button(View A ${this.testA.str}).onClick(() =>{ 
        this.index += 1; 
        this.testA.str = ${this.index} : Test A String 
      }) 
    }.margin({top : 10 }) 
  } 
}

ohpm install class-transformer 
ohpm install reflect-metadata