媒体子系统是 OpenHarmony 中重要的子系统，可以提供音视频播放能力。
媒体子系统为开发者提供一套简单且易于理解的接口，使得开发者能够方便接入系统并使用系统的媒体资源。
媒体子系统提供以下常用功能如下：
①音视频播放（AVPlayer9+），AudioPlayer6+ 和 VideoPlayer8+ 整合，升级了状态机和错误码，推荐使用。
②音视频录制（AVRecorder9+），AudioRecorder6+ 和 VideoRecorder9+ 整合，推荐使用。
③音频播放（AudioPlayer6+），AVPlayer9+ 发布后停止维护，请使用 AVPlayer9+。
④视频播放（VideoPlayer8+），AVPlayer9+ 发布后停止维护，请使用 AVPlayer9+。
⑤音频录制（AudioRecorder6+），AVRecorder9+ 发布后停止维护，请使用 AVRecorder9+。
⑥视频录制（VideoRecorder9+），AVRecorder9+ 发布后停止维护，请使用 AVRecorder9+。
从 3.2 开始 OpenHarmony 推出了 AVPlayer 和 AVRecorder 接口，之前的 VideoPlayer、AudioPlayer 这些接口会停止维护，所以我们今天学习下怎么使用 AVPlayer 接口。
导入模块
importmediafrom@ohos.multimedia.media;创建 avplayer：
this.avPlayer=awaitmedia.createAVPlayer()如上，我们使用的是 promise 接口，对应的接口定义为：
/** *CreatesanAVPlayerinstance. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackCallbackusedtoreturnAVPlayerinstanceiftheoperationissuccessful;returnsnullotherwise. *@throws{BusinessError}5400101-Nomemory.Returnbycallback. */ functioncreateAVPlayer(callback:AsyncCallback):void; /** *CreatesanAVPlayerinstance. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnAVPlayerinstanceiftheoperationissuccessful;returnsnullotherwise. *@throws{BusinessError}5400101-Nomemory.Returnbypromise. */ functioncreateAVPlayer():Promise; 注册 avplayer 回调： //注册状态变化回调，不同状态时做不同动作 avPlayer.on(stateChange,async(state,reason)=>{ …… }） //注册时间变化回调，方便更新进度条时间 avPlayer.on(timeUpdate,(time:number)=>{ …… }) avplayer 播放流程： graphLR 赋值avPlayer.url开始播放–>回调进入initialized–>赋值avPlayer.surfaceId–>avPlayer.prepare–>回调进入prepared–>avPlayer.play //视频播放伪代码 asyncavPlayerDemo(){ this.avPlayer.on(stateChange,async(state,reason)=>{ switch(state){ caseidle://成功调用reset接口后触发该状态机上报 console.info(TAG+stateidlecalled) this.avPlayer.release()//释放avplayer对象 break; caseinitialized://avplayer设置播放源后触发该状态上报 console.info(TAG+stateinitializedcalled) this.avPlayer.surfaceId=this.surfaceID//设置显示画面，当播放的资源为纯音频时无需设置 this.avPlayer.prepare().then(()=>{ console.info(TAG+preparesuccess); },(err)=>{ console.error(TAG+preparefiled,errormessageis:+err.message) }) break; caseprepared://prepare调用成功后上报该状态机 console.info(TAG+statepreparedcalled) this.avPlayer.play()//调用播放接口开始播放 break; caseplaying://play成功调用后触发该状态机上报 console.info(TAG+stateplayingcalled) if(this.count==0){ this.avPlayer.pause()//调用暂停播放接口 }else{ this.avPlayer.seek(10000,media.SeekMode.SEEK_PREV_SYNC)//前向seek置10秒处,触发seekDone回调函数 } break; casepaused://pause成功调用后触发该状态机上报 console.info(TAG+statepausedcalled) if(this.count==0){ this.count++ this.avPlayer.play()//继续调用播放接口开始播放 } break; casecompleted://播放结束后触发该状态机上报 console.info(TAG+statecompletedcalled) this.avPlayer.stop()//调用播放结束接口 break; casestopped://stop接口成功调用后触发该状态机上报 console.info(TAG+statestoppedcalled) this.avPlayer.reset()//调用reset接口初始化avplayer状态 break; casereleased: console.info(TAG+statereleasedcalled) break; caseerror: console.info(TAG+stateerrorcalled) break; default: console.info(TAG+unkownstate:+state) break; } }) //创建avPlayer实例对象 this.avPlayer=awaitmedia.createAVPlayer() letfdPath=fd:// letpathDir=”/data/storage/el2/base/haps/entry/files”//pathDir在FA模型和Stage模型的获取方式不同，请参考开发步骤首行的说明，根据实际情况自行获取。 //path路径的码流可通过”hdcfilesendD:xxxH264_AAC.mp4/data/app/el2/100/base/ohos.acts.multimedia.media.avplayer/haps/entry/files”命令，将其推送到设备上 letpath=pathDir+/H264_AAC.mp4 letfile=awaitfs.open(path) fdPath=fdPath++file.fd //赋值url后就会进入stateChangecallback this.avPlayer.url=fdPath } 其他播放控制接口： /** *Prepareaudio/videoplayback,itwillrequestresourceforplaying. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackAcallbackinstanceusedtoreturnwhenpreparecompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbycallback. *@throws{BusinessError}5400106-Unsupportformat.Returnbycallback. */ prepare(callback:AsyncCallback):void; /** *Prepareaudio/videoplayback,itwillrequestresourceforplaying. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnwhenpreparecompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbypromise. *@throws{BusinessError}5400106-Unsupportformat.Returnbypromise. */ prepare():Promise; /** *Playaudio/videoplayback. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackAcallbackinstanceusedtoreturnwhenplaycompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbycallback. */ play(callback:AsyncCallback):void; /** *Playaudio/videoplayback. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnwhenplaycompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbypromise. */ play():Promise; /** *Pauseaudio/videoplayback. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackAcallbackinstanceusedtoreturnwhenpausecompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbycallback. */ pause(callback:AsyncCallback):void; /** *Pauseaudio/videoplayback. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnwhenpausecompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbypromise. */ pause():Promise; /** *Stopaudio/videoplayback. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackAcallbackinstanceusedtoreturnwhenstopcompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbycallback. */ stop(callback:AsyncCallback):void; /** *Stopaudio/videoplayback. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnwhenstopcompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbypromise. */ stop():Promise; /** *ResetAVPlayer,itwilltoidlestateandcansetsrcagain. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackAcallbackinstanceusedtoreturnwhenresetcompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbycallback. */ reset(callback:AsyncCallback):void; /** *ResetAVPlayer,itwilltoidlestateandcansetsrcagain. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnwhenresetcompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbypromise. */ reset():Promise; /** *ReleasesresourcesusedforAVPlayer. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramcallbackAcallbackinstanceusedtoreturnwhenreleasecompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbycallback. */ release(callback:AsyncCallback):void; /** *ReleasesresourcesusedforAVPlayer. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@returnsAPromiseinstanceusedtoreturnwhenreleasecompleted. *@throws{BusinessError}5400102-Operationnotallowed.Returnbypromise. */ release():Promise; /** *Jumpstothespecifiedplaybackposition. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtimeMsPlaybackpositiontojump,shouldbein[0,duration]. *@parammodeSee@SeekMode. */ seek(timeMs:number,mode?void; 其他回调接口： /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackstateChangeevent. */ on(type:stateChange,callback:(state:AVPlayerState,reason:StateChangeReason)=>void):void; off(type:stateChange):void; /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackvolumeevent. */ on(type:volumeChange,callback:Callback):void; off(type:volumeChange):void; /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackendofstream */ on(type:endOfStream,callback:Callback):void; off(type:endOfStream):void; /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackseekDoneevent. */ on(type:seekDone,callback:Callback):void; off(type:seekDone):void; /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackspeedDoneevent. */ on(type:speedDone,callback:Callback):void; off(type:speedDone):void; /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybacksetBitrateDoneevent. */ on(type:bitrateDone,callback:Callback):void; off(type:bitrateDone):void; /** *LRegisterorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybacktimeUpdateevent. */ on(type:timeUpdate,callback:Callback):void; off(type:timeUpdate):void; /** *Registerorunregisterlistensformediaplaybackevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackdurationUpdateevent. */ on(type:durationUpdate,callback:Callback):void; off(type:durationUpdate):void; /** *Registerorunregisterlistensforvideoplaybackbufferingevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackbufferingupdateeventtolistenfor. *@paramcallbackCallbackusedtolistenforthebufferingupdateevent,returnBufferingInfoTypeandthevalue. */ on(type:bufferingUpdate,callback:(infoType:BufferingInfoType,value:number)=>void):void; off(type:bufferingUpdate):void; /** *Registerorunregisterlistensforstartrendervideoframeevents. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackeventreturn. */ on(type:startRenderFrame,callback:Callback):void; off(type:startRenderFrame):void; /** *Registerorunregisterlistensforvideosizechangeevent. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackeventreturnvideosize. */ on(type:videoSizeChange,callback:(width:number,height:number)=>void):void; off(type:videoSizeChange):void; /** *Registerorunregisterlistensforaudiointerruptevent,referto{@link#audio.InterruptEvent} *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackeventreturnaudiointerruptinfo. */ on(type:audioInterrupt,callback:(info:audio.InterruptEvent)=>void):void; off(type:audioInterrupt):void; /** *RegisterorunregisterlistensforavailablebitratelistcollectcompletedeventsforHLSprotocolstreamplayback. *Thiseventwillbereportedafterthe{@link#prepare}called. *@since9 *@syscapSystemCapability.Multimedia.Media.AVPlayer *@paramtypeTypeoftheplaybackeventtolistenfor. *@paramcallbackCallbackusedtolistenfortheplaybackeventreturnavailablebitratelist. */ on(type:availableBitrates,callback:(bitrates:Array)=>void):void; off(type:availableBitrates):void;简单样例
界面：
build(){ Stack({alignContent:Alignment.Center}){ if(this.isShowMenu){ Column(){ //视频名称 PlayTitle({title:this.displayName,handleBack:this.handleBack}) Row(){ //播放控件 PreVideo({handleClick:this.handlePrevClick}) PlayButton({isPlaying:$isPlaying}) NextVideo({handleClick:this.handleNextClick}) } .margin({top:40%}) Blank() //时间刻度 Row(){ Text(getTimeString(this.currentTime)) .fontSize(25) .fontColor(Color.White) Blank() Text(this.fileAsset?getTimeString(this.fileAsset.duration):00:00) .fontSize(25) .fontColor(Color.White) } .width(95%) //进度条 Slider({value:this.fileAsset?this.currentTime/this.fileAsset.duration*100:0}) .width(92%) .selectedColor(Color.White) .onChange((value:number)=>{ Logger.info(TAG,seektimechange) this.currentTime=this.fileAsset.duration*value/100 this.videoPlayer.seek(this.currentTime) }) } .height(100%) .zIndex(2) } Row(){ XComponent({ id:componentId, type:surface, controller:this.mxcomponentController }) .onLoad(()=>{ Logger.info(TAG,onLoadiscalled) this.playVideo() }) .width(100%) .aspectRatio(this.ratio) } .height(100%) .width(100%) .justifyContent(FlexAlign.Center) } .width(100%) .height(100%) .backgroundColor(Color.Black) .onClick(()=>{ this.isShowMenu=!this.isShowMenu }) } 播放： //根据视频文件获取视频源尺寸并生成surface //视频文件的路径在/storage/media/100/local/files/Videos asyncprepareVideo(){ this.ratio=this.fileAsset.width/this.fileAsset.height this.mxcomponentController.setXComponentsurfaceSize({ surfaceWidth:this.fileAsset.width, surfaceHeight:this.fileAsset.height }) this.surfaceId=this.mxcomponentController.getXComponentsurfaceId() this.fd=awaitthis.fileAsset.open(Rw) Logger.info(TAG,`fd://${this.fd}`) returnfd://+this.fd } //初始化视频文件并初始化avplayer asyncplayVideo(){ Logger.info(TAG,playVideo) try{ awaitthis.getMediaList() letfdPath=awaitthis.prepareVideo() this.videoPlayer.on(timeUpdate,(time:number)=>{ console.info(timeUpdatesuccess,andnewtimeis:+time) this.currentTime=time; }) awaitthis.videoPlayer.initVideoPlayer(fdPath,this.surfaceId) this.isPlaying=true }catch(error){ Logger.info(TAG,`playVideoerror${JSON.stringify(error)}`) } }小结
参考链接：
https://gitee.com/openharmony/docs/blob/master/zh-cn/application-dev/reference/apis/js-apis-media.md#play9审核编辑：汤梓红
