HarmonyOS 鸿蒙Next播放音频

使用AvPlayer实现项目内音频文件的播放、暂停、停止等功能
 

Row() {
  ButtonSelectView({
    name: ‘加载资源’, onclick: () => {
      AvPlayerUtil.getInstance().loadResource(mContext, ‘sound_high_man.mp3’, (state) => {
        this.message = ‘当前播放器状态’ + state
      })
    }
  })
  ButtonSelectView({
    name: ‘播放’, onclick: () => {
      AvPlayerUtil.getInstance().play()
    }
  })
  ButtonSelectView({
    name: ‘暂停’, onclick: () => {
      AvPlayerUtil.getInstance().pause()
    }
  })
  ButtonSelectView({
    name: ‘释放资源’, onclick: () => {
      AvPlayerUtil.getInstance().release()
    }
  })
}
.width(‘100%’)
.justifyContent(FlexAlign.SpaceEvenly)
.margin(20)

/
 * 闲置状态
 */
let idle: string = ‘idle’
/
 * 资源初始化
 */
let initialized: string = ‘initialized’
/
 * 已准备
 */
let prepared: string = ‘prepared’
/
 * 正在播放
 */
let playing: string = ‘playing’
/
 * 暂停状态
 */
let paused: string = ‘paused’
/
 *  已结束
 */
let completed: string = ‘completed’
/
 *  已停止
 */
let stopped: string = ‘stopped’
/
 *  已销毁
 */
let released: string = ‘released’
/
 * 错误异常
 */
let error: string = 'error’

export class AvPlayerUtil {
  private static instance: AvPlayerUtil
  private avPlayer?: media.AVPlayer
  private onStateChange?: (state: string) => void

  private constructor() {
  }

  static getInstance(): AvPlayerUtil {
    if (AvPlayerUtil.instance == null) {
      AvPlayerUtil.instance = new AvPlayerUtil()
    }
    return AvPlayerUtil.instance
  }

  /
   * 加载资源文件
   * @param resName 项目中rawfile文件下的音视频资源文件的名字
   */
  async loadResource(mContext: common.UIAbilityContext, resName: string, onStateChange?: (state: string) => void) {
    this.onStateChange = onStateChange
    //如果播放器存在，并且运行中，先将原来的注销掉再创建新的并且加载资源
    if (this.avPlayer != null && this.avPlayer.state != ‘released’) {
      this.avPlayer.release()
    }
    //创建实例
    this.avPlayer = await media.createAVPlayer()
    //监听状态
    this.setAVPlayerCallback(this.avPlayer)
    let fileDescriptor = await mContext.resourceManager.getRawFd(resName)
    //加载资源
    this.avPlayer.fdSrc = { fd: fileDescriptor.fd, offset: fileDescriptor.offset, length: fileDescriptor.length }
  }

  /
   * 播放音视频
   */
  play() {
    return this.avPlayer?.play()
  }

  /
   * 暂停播放
   */
  pause() {
    return this.avPlayer?.pause()
  }

  /
   * 停止播放
   */
  stop() {
    return this.avPlayer?.stop()
  }

  /
   * 释放资源
   */
  release() {
    return this.avPlayer?.release()
  }


  /**
   * 监听运行状态
   */
  private setAVPlayerCallback(avPlayer: media.AVPlayer) {
    avPlayer.on(‘error’, (err: BusinessError) => {
      avPlayer.reset(); // 调用reset重置资源，触发idle状态
    })
    avPlayer.on(‘stateChange’, async (state: string, reason: media.StateChangeReason) => {
      if (this.onStateChange != null) {
        this.onStateChange(state)
      }
      switch (state) {
        case idle: // 闲置状态
          avPlayer.release(); // 调用release接口销毁实例对象
          break;
        case initialized: //资源初始化
          avPlayer.prepare(); //调用准备方法
          break;
        case stopped: //播放停止
          avPlayer.reset(); //重置资源
          break;
        case error:
          avPlayer.reset(); //重置资源
          break
      }
    })
  }
}