HarmonyOS CustomDialogController如何判断是否在显示？

目前自定义弹窗没有提供判断展示状态的方法

只能参考下面方案代替：

设置一个状态变量，开启弹窗时设置为true，关闭弹窗时设置为false

参考下面demo：

@CustomDialog
struct CustomDialogExample {
  cancel?: () => void
  confirm?: () => void
  controller: CustomDialogController
  build() {
    Column() {
      Text('我是内容').fontSize(20).margin({ top: 10, bottom: 10 })
      Flex({ justifyContent: FlexAlign.SpaceAround }) {
        Button('cancel')
          .onClick(() => {
            this.controller.close()
            if (this.cancel) {
              this.cancel()
            }
          }).backgroundColor(0xffffff).fontColor(Color.Black)
        Button('confirm')
          .onClick(() => {
            this.controller.close()
            if (this.confirm) {
              this.confirm()
            }
          }).backgroundColor(0xffffff).fontColor(Color.Red)
      }.margin({ bottom: 10 })
    }
  }
}

@Entry
@Component
struct CustomDialogUser {
  @State isShow : boolean = false;//添加一个变量来表示当前弹窗是否在显示
  dialogController: CustomDialogController = new CustomDialogController({
    builder: CustomDialogExample({
      cancel: ()=> {
        this.isShow = false;//开启弹窗时设置为false
        this.onCancel()
      },
      confirm: ()=> {
        this.isShow = false;//开启弹窗时设置为false
        this.onAccept()
      },
    }),
  })

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

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

  build() {
    Column() {
      Button('click me')
        .onClick(() => {
          this.isShow = true;//开启弹窗时设置为true
          this.dialogController.open()
        })
    }.width('100%').margin({ top: 5 })
  }
}