采用 AAOS 的车载 Android 系统一次性集成即可让车规硬件直接运行完整 Android 生态通过 CarService 深度控制空调、车窗等车控功能使车载的接口标准化规范化显著缩短开发周期、降低维护成本并拓展持续盈利空间下面介绍aaos应用适配的架构设计以车载语音助手为例从给上层调用的carlib接口到carservice服务,到hal层语音相关接口应用案例如下。1、在carlib中添加应用与carservice的aidl接口及调用方法在\android11.0\packages\servicesCar\car-lib\src\android\car\路径下添加Voice目录在Voice目录下添加语音助手的上层调用及数据回调接口如下语音助手的上层调用接口android11.0\packages\servicesCar\car-lib\src\android\car\IVoiceRecognitionService.aidlinterface IVoiceRecognitionService { void startVoiceRecognition(); void stopVoiceRecognition(); void setVoiceCallback(IVoiceCallback callback); }语音助手的回调接口// android11.0\packages\servicesCar\car-lib\src\android\car\IVoiceCallback.aidlinterface IVoiceCallback { void onVoiceResult(String result); void onVoiceError(int errorCode); }语音接口管理类// android11.0\packages\servicesCar\car-lib\src\android\car\CarVoiceManager.javapublic class CarVoicemanager extends IVoiceCallback.Stub{ private IVoiceRecognitionService mIVoiceRecognitionService; private ListIVoiceCallback mVoiceCallbackListnew ArrayList(); private CarVoicemanager() { init(); } /** * 静态内部类方式构造单例线程安全 * hide */ private static class SingleHolder { static final CarVoicemanager sInstance new CarVoicemanager(); } /** * 内部类方式获取单例 * * return * hide */ NonNull public static CarVoicemanager getInstance() { return CarVoicemanager.SingleHolder.sInstance; } /** * 初始化服务 * //针对初始化做一些等待处理 * hide */ private void init() { try { IBinder mCarServiceBinder ServiceManager.getService(Car.CAR_SERVICE_BINDER_SERVICE_NAME); if (mCarServiceBinder null) { Log.e(TAG, car service not start, waited for car service !!!); return; } ICar mCarService ICar.Stub.asInterface(mCarServiceBinder); if (mCarService null) { Log.e(TAG, car service not register !!!); return; } IBinder binder mCarService.getCarService(Car.VOICE_SERVICE); if (binder null) { Log.e(TAG, voiceservice not register !!!); return; } mIVoiceRecognitionService IVoiceRecognitionService .Stub.asInterface(binder); if (mIVoiceRecognitionService null) { Log.e(TAG, mIVoiceRecognitionService get failed !!!); return; } } } catch (RemoteException e) { e.printStackTrace(); } } public void startVoiceRecognition(){ if(mIVoiceRecognitionService!null){ mIVoiceRecognitionService.startVoiceRecognition(); } } public void stopVoiceRecognition(){ if(mIVoiceRecognitionService!null){ mIVoiceRecognitionService.stopVoiceRecognition(); } } public void setVoiceCallback(IVoiceCallback callback){ if(!mVoiceCallbackList.contains(callback)){ mVoiceCallbackList.add(callback); } } Override void onVoiceResult(String result){ for(VoiceCallback callback:mVoiceCallbackList){ callback.onVoiceResult(result); } } Override void onVoiceError(int errorCode){ for(VoiceCallback callback:mVoiceCallbackList){ callback.onVoiceError(errorCode); } } }2、在CarService应用增加CarVoiceService及跟hal通信相关接口在// android11.0/packages/services/Car/service/src/com/android/car/目录下增加voice目录在目录下创建CarVoiceService类,如下public class CarVoiceService extends IVoiceRecognitionService.Stub implements CarServiceBase { private final static String TAG CarVoiceService; private final int START_VOICE_RECOGINZED 1; private final int STOP_VOICE_RECOGINZED 2; private VoiceMessage mVoiceMessage; private IHalVoice mIHalVoice; public CarVoiceService(NonNull Context context) { // hal接口通过hidl接口生成IHalVoice.java类通过getService可以获取接口对象 mIHalVoice IHalVoice.getService(); mVoiceMessage new mVoiceMessage(mHal); mVoiceMessage.init(mIHalVoice); } Override public void startVoiceRecognition(){ mIHalVoice.sendVoiceCmdToCpp(START_VOICE_RECOGINZED); } Override public void stopVoiceRecognition(){ mIHalVoice.sendVoiceCmdToCpp(STOP_VOICE_RECOGINZED); } Override public void setVoiceCallback(IVoiceCallback callback){ mVoiceMessage.setVoiceCallback(callback); } }创建hal消息管理类// android11.0/packages/services/Car/service/src/com/android/car/voice/VoiceHalMessage.javapublic class VoiceHalMessage { private IVoiceCallback mVoiceCallback; private IHalVoice mIHalVoice; public VoiceHalMessage (mIHalVoice hal){ mIhalVoice hal; } public void init(){ mIhalVoice.registerLitener(mIHalVoiceCallback); } public void setCallbackListener(VoiceCallback listenter){ mVoiceCallback listenter; } private final IHalVoiceCallbackCallback mIHalVoiceCallback new IHalVoiceCallback.Stub() { Override public void onVoiceMessage(int code,String message) { if(code0){ mVoiceCallback.onVoiceResult(message); return; } mVoiceCallback.onVoiceError(message); } } }在// android11.0/packages/services/Car/service/src/com/android/car/ICarImpl.java类中public class ICarImpl{ peivate CarVoiceService mCarVoiceService; public ICarImpl(){ //省略 mCarVoiceService new mCarVoiceService(serviceContext); CarLocalServices.addService(CarVoiceService.class, mCarVoiceService); } Override public IBinder getCarService(String serviceName) { switch (serviceName) { //其他省略 case Car.VOICE_SERVICE: return mCarVoiceService; default: return null; } } }在// android11.0/packages/services/Android.bp如下android_app { name: CarService, srcs: car_service_sources, resource_dirs: [res], platform_apis: true, // Each update should be signed by OEMs certificate: platform, privileged: true, optimize: { proguard_flags_files: [proguard.flags], enabled: false, }, libs: [android.car], android_app { name: CarService, ... static_libs: [ car-frameworks-service, android.hardware.voice1.0-java-static, // -- 语音 HAL Java 依赖 ], } required: [privapp_whitelist_com.android.car], // Disable build in PDK, missing aidl import breaks build product_variables: { pdk: { enabled: false, }, }, }3、在hal层增加hidl接口及语音原子能力的相关接口在android11.0\hardware\interfaces\voice\目录下添加hal接口文集如下语音指令发送IVoiceHal.halpackage android.hardware.voice1.1; import 1.0::IVoiceHal; interface IVoiceHalextends 1.0::IVoiceHal{ sendVoiceCmdToCpp(int32_t code) } enum VoiceCmd : int32_t { START_VOICE_RECOGINZED 1, STOP_VOICE_RECOGINZED 2, };语音消息回调IHalVoiceCallback .halpackage android.hardware.voice1.1; import 1.0::IHalVoiceCallback ; interface IHalVoiceCallback extends 1.0::IHalVoiceCallback { oneway onVoiceMessage(int32_t code,String message ); }语音接口C 实现android11.0/hardware/interfaces/voice/default/VoiceRecognition.h把指令 enum 同步过来并声明 sendVoiceCmd 接口C 语音接口实现android11.0/hardware/interfaces/voice/default/VoiceRecognition.cpp#include VoiceRecognition.h #include android-base/logging.h namespace android::hardware::voice::V1_0::implementation { bool VoiceRecognition::sendVoiceCmdToCpp(VoiceCmd cmd) { switch (cmd) { case VoiceCmd::START_VOICE_RECOGINZED: handleStart(); return true; case VoiceCmd::STOP_VOICE_RECOGINZED: handleStop(); return true; default: LOG(ERROR) Unknown voice cmd static_castint32_t(cmd); return false; } } void VoiceRecognition::startRecognition() { LOG(INFO) native START_VOICE_RECOGINZED; // 这里放入启动识别算法 / 打开 MIC / 通知 DSP 等代码 } void VoiceRecognition::stopRecognition() { LOG(INFO) native STOP_VOICE_RECOGINZED; // 这里放入停止识别算法 / 关闭 MIC / 通知 DSP 等代码 } }在android11.0/hardware/interfaces/voice/目录下添加Android.bphidl_interface { name: android.hardware.voice1.0, root: android.hardware, vndk: { enabled: true, }, srcs: [ types.hal, IHalVoiceCallback.hal, IVoiceHal.hal, ], interfaces: [ android.hidl.base1.0, ], gen_java: true, }