HarmonyOS AVPlayer获取媒体信息示例代码运行报错

AVPlayer获取音频信息，按照官方文档的说明demo去获取媒体信息一直报错。

代码：

function printfItemDescription(obj: media.MediaDescription, key: string) {
  let value: Object = obj[key];
  // 通过key值获取对应的value。key值具体可见[MediaDescriptionKey]
  //对应key值得value。其类型可为任意类型，具体key对应value的类型可参考[MediaDescriptionKey]
  console.log(`audio key is: ${key}, value is: ${value}`)
}

export function mediaInfo(path: string) {
  let avPlayer: media.AVPlayer | undefined = undefined;
  media.createAVPlayer((err: BusinessError, player: media.AVPlayer) => {
    if(player != null) {
      avPlayer = player;
      avPlayer.url = 'xxx'
      console.info(`Succeeded in creating AVPlayer`);
      avPlayer.getTrackDescription((error: BusinessError, arrList: Array<media.MediaDescription>) => {
        if (arrList != null) {
          for (let i = 0; i < arrList.length; i++) {
            let property: object = arrList[i]
            printfItemDescription(arrList[i], media.MediaDescriptionKey.MD_KEY_DURATION);

          }
        } else {
          console.error(`Failed to get TrackDescription, error:${error}`);
        }
      });
    } else {
      console.error(`Failed to create AVPlayer, error message:${err.message}`);
    }
  });
}
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报错信息：

current state unsupport get track description, code=5400102
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