HarmonyOS鸿蒙Next中AVPlayer的状态机具体该怎么处理

//avplayerManager.ets：
import { media } from '@kit.MediaKit';
import { BusinessError } from '@kit.BasicServicesKit';

const TAG = '[AvPlayer]  '

@ObservedV2
export class AudioPlayManager {
  private avPlayer: media.AVPlayer | null = null
  @Trace audioDuration: number = 0
  @Trace currAudioTime: number = 0
  @Trace isPlaying: boolean = false
  @Trace audioPlayState: media.AVPlayerState = 'idle';

  // 注册avplayer回调函数。
  setAVPlayerCallback(avPlayer: media.AVPlayer) {
    // seek操作结果回调函数。
    avPlayer.on('seekDone', (seekDoneTime: number) => {
      console.info(`${TAG} on seekDone, seek time is ${seekDoneTime}`);
    });
    // error回调监听函数,当avPlayer在操作过程中出现错误时调用 reset接口触发重置流程。
    avPlayer.on('error', (err: BusinessError) => {
      console.error(`${TAG} on error, code is ${err.code}, message is ${err.message}`);
      avPlayer.reset(); // 调用reset重置资源，触发idle状态。
    });
    avPlayer.on('timeUpdate', (time: number) => {
      console.info(`${TAG} on timeUpdate :  ${time}`);
      this.currAudioTime = time
    });
    avPlayer.on('durationUpdate', (time: number) => {
      console.info(TAG + `on durationUpdate: ${time}`)
      this.audioDuration = time;
    })
    // 状态机变化回调函数。
    avPlayer.on('stateChange', async (state: string, reason: media.StateChangeReason) => {
      switch (state) {
        case 'idle': // 成功调用reset接口后触发该状态机上报。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          // avPlayer.release(); // 调用release接口销毁实例对象。
          break;
        case 'initialized': // avplayer 设置播放源后触发该状态上报。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          // avPlayer.audioRendererInfo = {
          //   usage: audio.StreamUsage.STREAM_USAGE_MUSIC, // 音频流使用类型：音乐。根据业务场景配置，参考StreamUsage。
          //   rendererFlags: 0 // 音频渲染器标志。
          // };
          avPlayer.prepare();
          break;
        case 'prepared': // prepare调用成功后上报该状态机。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          // this.audioDuration = avPlayer.duration
          break;
        case 'playing': // play成功调用后触发该状态机上报。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          break;
        case 'paused': // pause成功调用后触发该状态机上报。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          avPlayer.pause()
          break;
        case 'completed': // 播放结束后触发该状态机上报。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          this.resetCurrAudioPlayStatusInfo();
          break;
        case 'stopped': // stop接口成功调用后触发该状态机上报。
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          break;
        case 'released':
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          this.setAudioPlayState(avPlayer.state)
          break;
        default:
          console.info(`${TAG} 状态机 audioPlayState: ${avPlayer.state}`);
          break;
      }
    });
  }

  //设置当前音频播放状态
  setAudioPlayState(state: media.AVPlayerState) {
    this.audioPlayState = state;
    console.info(TAG + `setAudioPlayState audioPlayState: ${this.audioPlayState}`)
  }

  //音频播放
  async setAudioSrcToPrepared(audioSrc: string) {
    // 创建avPlayer实例对象。
    this.avPlayer = await media.createAVPlayer();
    //设置状态机
    this.setAVPlayerCallback(this.avPlayer!);
    //设置 音频url，状态自动跳至 initialized
    this.avPlayer!.url = audioSrc;
  }
  
  async startPlay() {
    this.isPlaying = true
    try {
      this.avPlayer?.play()
    }catch (err){
      let error:BusinessError = err as BusinessError
    }
  }

  async stopPlay() {
    this.avPlayer?.prepare()
    this.isPlaying = false
  }

  async release() {
    this.avPlayer?.release()
    this.isPlaying = false
  }

  async reset() {
    this.isPlaying = false
    this.currAudioTime = 0
    this.avPlayer?.prepare();
    // this.avPlayer?.release()
    this.avPlayer = null;
  }

  //重置当前音频播放状态信息
  resetCurrAudioPlayStatusInfo() {
    this.isPlaying = false
    this.currAudioTime = 0
    this.setAudioPlayState('stopped');
  }

  async seek(value: number) {
    this.avPlayer?.seek(value)
  }
}

//Index
import { AudioPlayManager } from './avplayerManager';

@Entry
@Component
struct Index {
  avplayerManager:AudioPlayManager = new AudioPlayManager()

  build() {
    Column({space:20}){
      Button('AVPlayer实例化')
        .onClick(()=>{
          this.avplayerManager.setAudioSrcToPrepared('')
          // 在该函数中传入音频文件url
        })
      Button('开始播放(确保实例化完成之后再点击播放)')
        .onClick(()=>{
          this.avplayerManager.startPlay()
        })
      Button('暂停播放')
        .onClick(()=>{
          this.avplayerManager.stopPlay()
        })
      Button('重置播放')
        .onClick(()=>{
          this.avplayerManager.reset()
        })
      Button('销毁资源')
        .onClick(()=>{
          this.avplayerManager.release()
        })
    }
    .width('100%')
    .justifyContent(FlexAlign.Center)
    .alignItems(HorizontalAlign.Center)
  }
}