HarmonyOS textarea展示最新数据问题

示例参考如下：

// xxx.ets
@Entry
@Component
struct TextAreaExample {
  @State text: string = ''
  @State positionInfo: CaretOffset = { index: 0, x: 0, y: 0 }
  controller: TextAreaController = new TextAreaController()
  @State maxLength: number= 0

  build() {
    Column() {
      TextArea({
        text: this.text,
        placeholder: 'The text area can hold an unlimited amount of text. input your word...',
        controller: this.controller
      })
        .placeholderFont({ size: 16, weight: 400 })
        .width(336)
        .height(56)
        .margin(20)
        .fontSize(16)
        .fontColor('#182431')
        .backgroundColor('#FFFFFF')
        .onChange((value: string) => {
          let Length: number= value.length;
          if(this.maxLength< Length){
            this.maxLength = Length
            console.log('length='+this.maxLength)
          }
          this.text = value
        })
      Text(this.text)

      Button('跳转到最后一行').onClick((event: ClickEvent) => {
        this.controller.caretPosition(this.maxLength)
      })
    }.width('100%').height('100%').backgroundColor('#F1F3F5')
  }
}

参考链接：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/ts-basic-components-textarea-V5