HarmonyOS 如何实现一个 60:00 这种倒计时字符的效果

请参考以下代码实现倒计时效果：

@Entry
@Component
struct Arc {
  @State countdownValue: number = 60;

  aboutToAppear(): void {
  }

  build() {
    Flex({ direction: FlexDirection.Column, alignItems: ItemAlign.Center, justifyContent: FlexAlign.Center }) {

      Text(this.countdownValue.toString())
        .backgroundColor(Color.Blue)
        .fontColor(Color.White)
        .width(100)
        .height(45)
        .textAlign(TextAlign.Center)
    }
    .width('100%')
    .height('100%')
  }

  onPageShow(): void {

    setInterval(() => {
      this.countdownValue--;
      if (this.countdownValue < 0) {
        clearInterval(this.countdownValue);
        return;
      }

    }, 1000);

  }
}