OpenHarmony音频流管理开发
AudioStreamManager提供了音频流管理的方法。开发者可以通过本博文了解应用如何通过AudioStreamManager管理音频流。
2、OpenHarmony音频流管理运作机制
该模块提供了音频流管理调用关系图
图1 音频流管理调用关系图
说明：在进行应用开发的过程中，开发者需要使用getStreamManager()创建一个AudioStreamManager实例，进而通过该实例管理音频流。开发者可通过调用on('audioRendererChange')、on('audioCapturerChange')监听音频播放应用和音频录制应用，在应用状态变化、设备变化、音频属性变化时获得通知。同时可通过off('audioRendererChange')、off('audioCapturerChange')取消相关事件的监听。与此同时，开发者可以通过调用（可选）使用getCurrentAudioRendererInfoArray()获取当前音频播放应用的音频流唯一ID、音频播放客户端的UID、音频状态等信息，同理可调用getCurrentAudioCapturerInfoArray()获取音频录制应用的信息。
3、OpenHarmony音频流管理开发开发指导
详细API含义可参考：音频管理API文档AudioStreamManager
(1).创建AudioStreamManager实例。
在使用AudioStreamManager的API前，需要使用getStreamManager()创建一个AudioStreamManager实例。
var audioManager = audio.getAudioManager();var audioStreamManager = audioManager.getStreamManager();(2).使用on（'audioRendererChange'）监听音频渲染器更改事件。 如果音频流监听应用需要在音频播放应用状态变化、设备变化、音频属性变化时获取通知，可以订阅该事件。更多事件请参考API参考文档。
audioStreamManager.on('audioRendererChange', (AudioRendererChangeInfoArray) => { for (let i = 0; i < AudioRendererChangeInfoArray.length; i++) { AudioRendererChangeInfo = AudioRendererChangeInfoArray[i]; console.info('## RendererChange on is called for ' + i + ' ##'); console.info('StreamId for ' + i + ' is:' + AudioRendererChangeInfo.streamId); console.info('ClientUid for ' + i + ' is:' + AudioRendererChangeInfo.clientUid); console.info('Content for ' + i + ' is:' + AudioRendererChangeInfo.rendererInfo.content); console.info('Stream for ' + i + ' is:' + AudioRendererChangeInfo.rendererInfo.usage); console.info('Flag ' + i + ' is:' + AudioRendererChangeInfo.rendererInfo.rendererFlags); console.info('State for ' + i + ' is:' + AudioRendererChangeInfo.rendererState); var devDescriptor = AudioRendererChangeInfo.deviceDescriptors; for (let j = 0; j < AudioRendererChangeInfo.deviceDescriptors.length; j++) { console.info('Id:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].id); console.info('Type:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].deviceType); console.info('Role:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].deviceRole); console.info('Name:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].name); console.info('Address:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].address); console.info('SampleRates:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].sampleRates[0]); console.info('ChannelCounts' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].channelCounts[0]); console.info('ChannelMask:' + i + ':' + AudioRendererChangeInfo.deviceDescriptors[j].channelMasks); } }});(3).使用off（'audioRendererChange'）取消监听音频渲染器更改事件。
audioStreamManager.off('audioRendererChange');console.info('######### RendererChange Off is called #########');(4).使用on（'audioCapturerChange'）监听音频捕获器更改事件。 如果音频流监听应用需要在音频录制应用状态变化、设备变化、音频属性变化时获取通知，可以订阅该事件。更多事件请参考API参考文档。
audioStreamManager.on('audioCapturerChange', (AudioCapturerChangeInfoArray) => { for (let i = 0; i < AudioCapturerChangeInfoArray.length; i++) { console.info(' ## audioCapturerChange on is called for element ' + i + ' ##'); console.info('StreamId for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].streamId); console.info('ClientUid for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].clientUid); console.info('Source for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].capturerInfo.source); console.info('Flag ' + i + 'is:' + AudioCapturerChangeInfoArray[i].capturerInfo.capturerFlags); console.info('State for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].capturerState); for (let j = 0; j < AudioCapturerChangeInfoArray[i].deviceDescriptors.length; j++) { console.info('Id:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].id); console.info('Type:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].deviceType); console.info('Role:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].deviceRole); console.info('Name:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].name); console.info('Address:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].address); console.info('SampleRates:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].sampleRates[0]); console.info('ChannelCounts' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].channelCounts[0]); console.info('ChannelMask:' + i + ':' + AudioCapturerChangeInfoArray[i].deviceDescriptors[j].channelMasks); } }});(5).使用off（'audioCapturerChange'）取消监听音频捕获器更改事件。
audioStreamManager.off('audioCapturerChange');console.info('######### CapturerChange Off is called #########');(6).使用getCurrentAudioRendererInfoArray()获取当前音频渲染器的信息。 该接口可获取音频流唯一ID，音频播放客户端的UID，音频状态以及音频播放器的其他信息。需注意的是若对第三方音频流监听应用未配置ohos.permission.USE_BLUETOOTH权限，则查询到的设备名称和设备地址为空字符串，若正确配置权限，则显示的实际的设备名称和设备地址信息。
await audioStreamManager.getCurrentAudioRendererInfoArray().then( function (AudioRendererChangeInfoArray) { console.info('######### Get Promise is called ##########'); if (AudioRendererChangeInfoArray != null) { for (let i = 0; i < AudioRendererChangeInfoArray.length; i++) { AudioRendererChangeInfo = AudioRendererChangeInfoArray[i]; console.info('StreamId for ' + i +' is:' + AudioRendererChangeInfo.streamId); console.info('ClientUid for ' + i + ' is:' + AudioRendererChangeInfo.clientUid); console.info('Content ' + i + ' is:' + AudioRendererChangeInfo.rendererInfo.content); console.info('Stream' + i +' is:' + AudioRendererChangeInfo.rendererInfo.usage); console.info('Flag' + i + ' is:' + AudioRendererChangeInfo.rendererInfo.rendererFlags);console.info('State for ' + i + ' is:' + AudioRendererChangeInfo.rendererState); var devDescriptor = AudioRendererChangeInfo.deviceDescriptors; for (let j = 0; j { console.log('getCurrentAudioRendererInfoArray :ERROR: ' + err.message);});(7).使用getCurrentAudioCapturerInfoArray()获取当前音频捕获器的信息。 该接口可获取音频流唯一ID，音频录制客户端的UID，音频状态以及音频捕获器的其他信息。需注意的是若对第三方音频流监听应用未配置ohos.permission.USE_BLUETOOTH权限，则查询到的设备名称和设备地址为空字符串，若正确配置权限，则显示的实际的设备名称和设备地址信息。
await audioStreamManager.getCurrentAudioCapturerInfoArray().then( function (AudioCapturerChangeInfoArray) { console.info('getCurrentAudioCapturerInfoArray： **** Get Promise Called ****'); if (AudioCapturerChangeInfoArray != null) { for (let i = 0; i < AudioCapturerChangeInfoArray.length; i++) { console.info('StreamId for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].streamId); console.info('ClientUid for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].clientUid); console.info('Source for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].capturerInfo.source); console.info('Flag ' + i + 'is:' + AudioCapturerChangeInfoArray[i].capturerInfo.capturerFlags); console.info('State for ' + i + 'is:' + AudioCapturerChangeInfoArray[i].capturerState); var devDescriptor = AudioCapturerChangeInfoArray[i].deviceDescriptors; for (let j = 0; j { console.log('getCurrentAudioCapturerInfoArray :ERROR: ' + err.message);});