HarmonyOS 父组件的@state变量更新后子组件不生效

该问题中自定义弹窗@Prop、@ObjectLink不适用此场景。可以使用@Link装饰器。

或者可以使用类封装该变量，参考如下代码：

//@Observed
class ClassA {
  public c: string = '';

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

// xxx.ets
@CustomDialog
struct CustomDialogExample {

  @Prop str: ClassA
  @Link str1: string
  controller?: CustomDialogController
  cancel: () => void = () => {
  }
  confirm: () => void = () => {
  }
  build() {
    Column() {
      Text(this.str.c)
        .fontSize(30)
        .height(100)
      Text(this.str1)
        .fontSize(30)
        .height(100)
      Button('点我关闭弹窗')
        .onClick(() => {
          if (this.controller != undefined) {
            this.controller.close()
          }
        })
        .margin(20)
    }
  }
}
@Entry
@Component
struct CustomDialogUser {
  @State str:ClassA = new ClassA('hello world')
  @State str1: string = 'hello world1'
  dialogController: CustomDialogController | null = new CustomDialogController({
    builder: CustomDialogExample({
      str: this.str,
      str1: $str1,
      cancel: ()=> { this.onCancel() },
      confirm: ()=> { this.onAccept() }
    }),
    cancel: this.existApp,
    autoCancel: true,
    alignment: DialogAlignment.Center,
    offset: { dx: 0, dy: -20 },
    gridCount: 4,
    showInSubWindow: true,
    isModal: true,
    customStyle: false,
    cornerRadius: 10,
  })
  aboutToAppear(): void {
    setTimeout(() => {
      this.str.c = '你好，世界'
      this.str1 = '你好，世界'
      console.log('delay 5s');
    }, 5000);
  }

  // 在自定义组件即将析构销毁时将dialogControlle置空
  aboutToDisappear() {
    this.dialogController = null // 将dialogController置空
  }

  onCancel() {
    console.info('Callback when the first button is clicked')
  }

  onAccept() {
    console.info('Callback when the second button is clicked')
  }

  existApp() {
    console.info('Click the callback in the blank area')
  }

  build() {
    Column() {
      Text(this.str.c)
        .height(100).width('100%')
      Text(this.str1)
        .height(100).width('100%')
      Button('click me')
        .onClick(() => {
          if (this.dialogController != null) {
            this.dialogController.open()
          }
        }).backgroundColor(0x317aff)
    }.width('100%').margin({ top: 5 })
  }
}