VoiceInteractionService.java revision ffeecb1bfb9b71f4b62c9ef1fbf7b58a7a63f655
1/** 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package android.service.voice; 18 19import android.annotation.SdkConstant; 20import android.app.Service; 21import android.content.ComponentName; 22import android.content.Context; 23import android.content.Intent; 24import android.hardware.soundtrigger.KeyphraseEnrollmentInfo; 25import android.os.Bundle; 26import android.os.Handler; 27import android.os.IBinder; 28import android.os.Message; 29import android.os.RemoteException; 30import android.os.ServiceManager; 31import android.provider.Settings; 32 33import com.android.internal.annotations.VisibleForTesting; 34import com.android.internal.app.IVoiceInteractionManagerService; 35 36import java.io.FileDescriptor; 37import java.io.PrintWriter; 38import java.util.Locale; 39 40 41/** 42 * Top-level service of the current global voice interactor, which is providing 43 * support for hotwording, the back-end of a {@link android.app.VoiceInteractor}, etc. 44 * The current VoiceInteractionService that has been selected by the user is kept 45 * always running by the system, to allow it to do things like listen for hotwords 46 * in the background to instigate voice interactions. 47 * 48 * <p>Because this service is always running, it should be kept as lightweight as 49 * possible. Heavy-weight operations (including showing UI) should be implemented 50 * in the associated {@link android.service.voice.VoiceInteractionSessionService} when 51 * an actual voice interaction is taking place, and that service should run in a 52 * separate process from this one. 53 */ 54public class VoiceInteractionService extends Service { 55 /** 56 * The {@link Intent} that must be declared as handled by the service. 57 * To be supported, the service must also require the 58 * {@link android.Manifest.permission#BIND_VOICE_INTERACTION} permission so 59 * that other applications can not abuse it. 60 */ 61 @SdkConstant(SdkConstant.SdkConstantType.SERVICE_ACTION) 62 public static final String SERVICE_INTERFACE = 63 "android.service.voice.VoiceInteractionService"; 64 65 /** 66 * Name under which a VoiceInteractionService component publishes information about itself. 67 * This meta-data should reference an XML resource containing a 68 * <code><{@link 69 * android.R.styleable#VoiceInteractionService voice-interaction-service}></code> tag. 70 */ 71 public static final String SERVICE_META_DATA = "android.voice_interaction"; 72 73 /** 74 * Flag for use with {@link #showSession: request that the session be started with 75 * assist data from the currently focused activity. 76 */ 77 public static final int START_WITH_ASSIST = 1<<0; 78 79 IVoiceInteractionService mInterface = new IVoiceInteractionService.Stub() { 80 @Override public void ready() { 81 mHandler.sendEmptyMessage(MSG_READY); 82 } 83 @Override public void shutdown() { 84 mHandler.sendEmptyMessage(MSG_SHUTDOWN); 85 } 86 @Override public void soundModelsChanged() { 87 mHandler.sendEmptyMessage(MSG_SOUND_MODELS_CHANGED); 88 } 89 }; 90 91 MyHandler mHandler; 92 93 IVoiceInteractionManagerService mSystemService; 94 95 private final Object mLock = new Object(); 96 97 private KeyphraseEnrollmentInfo mKeyphraseEnrollmentInfo; 98 99 private AlwaysOnHotwordDetector mHotwordDetector; 100 101 static final int MSG_READY = 1; 102 static final int MSG_SHUTDOWN = 2; 103 static final int MSG_SOUND_MODELS_CHANGED = 3; 104 105 class MyHandler extends Handler { 106 @Override 107 public void handleMessage(Message msg) { 108 switch (msg.what) { 109 case MSG_READY: 110 onReady(); 111 break; 112 case MSG_SHUTDOWN: 113 onShutdownInternal(); 114 break; 115 case MSG_SOUND_MODELS_CHANGED: 116 onSoundModelsChangedInternal(); 117 break; 118 default: 119 super.handleMessage(msg); 120 } 121 } 122 } 123 124 /** 125 * Check whether the given service component is the currently active 126 * VoiceInteractionService. 127 */ 128 public static boolean isActiveService(Context context, ComponentName service) { 129 String cur = Settings.Secure.getString(context.getContentResolver(), 130 Settings.Secure.VOICE_INTERACTION_SERVICE); 131 if (cur == null || cur.isEmpty()) { 132 return false; 133 } 134 ComponentName curComp = ComponentName.unflattenFromString(cur); 135 if (curComp == null) { 136 return false; 137 } 138 return curComp.equals(service); 139 } 140 141 /** 142 * Request that the associated {@link android.service.voice.VoiceInteractionSession} be 143 * shown to the user, starting it if necessary. 144 * @param args Arbitrary arguments that will be propagated to the session. 145 */ 146 public void showSession(Bundle args, int flags) { 147 if (mSystemService == null) { 148 throw new IllegalStateException("Not available until onReady() is called"); 149 } 150 try { 151 mSystemService.showSession(mInterface, args, flags); 152 } catch (RemoteException e) { 153 } 154 } 155 156 /** @hide */ 157 public void startSession(Bundle args, int flags) { 158 showSession(args, flags); 159 } 160 /** @hide */ 161 public void startSession(Bundle args) { 162 startSession(args, 0); 163 } 164 165 @Override 166 public void onCreate() { 167 super.onCreate(); 168 mHandler = new MyHandler(); 169 } 170 171 @Override 172 public IBinder onBind(Intent intent) { 173 if (SERVICE_INTERFACE.equals(intent.getAction())) { 174 return mInterface.asBinder(); 175 } 176 return null; 177 } 178 179 /** 180 * Called during service initialization to tell you when the system is ready 181 * to receive interaction from it. You should generally do initialization here 182 * rather than in {@link #onCreate}. Methods such as {@link #showSession} and 183 * {@link #createAlwaysOnHotwordDetector} 184 * will not be operational until this point. 185 */ 186 public void onReady() { 187 mSystemService = IVoiceInteractionManagerService.Stub.asInterface( 188 ServiceManager.getService(Context.VOICE_INTERACTION_MANAGER_SERVICE)); 189 mKeyphraseEnrollmentInfo = new KeyphraseEnrollmentInfo(getPackageManager()); 190 } 191 192 private void onShutdownInternal() { 193 onShutdown(); 194 // Stop any active recognitions when shutting down. 195 // This ensures that if implementations forget to stop any active recognition, 196 // It's still guaranteed to have been stopped. 197 // This helps with cases where the voice interaction implementation is changed 198 // by the user. 199 safelyShutdownHotwordDetector(); 200 } 201 202 /** 203 * Called during service de-initialization to tell you when the system is shutting the 204 * service down. 205 * At this point this service may no longer be the active {@link VoiceInteractionService}. 206 */ 207 public void onShutdown() { 208 } 209 210 private void onSoundModelsChangedInternal() { 211 synchronized (this) { 212 if (mHotwordDetector != null) { 213 // TODO: Stop recognition if a sound model that was being recognized gets deleted. 214 mHotwordDetector.onSoundModelsChanged(); 215 } 216 } 217 } 218 219 /** 220 * Creates an {@link AlwaysOnHotwordDetector} for the given keyphrase and locale. 221 * This instance must be retained and used by the client. 222 * Calling this a second time invalidates the previously created hotword detector 223 * which can no longer be used to manage recognition. 224 * 225 * @param keyphrase The keyphrase that's being used, for example "Hello Android". 226 * @param locale The locale for which the enrollment needs to be performed. 227 * @param callback The callback to notify of detection events. 228 * @return An always-on hotword detector for the given keyphrase and locale. 229 */ 230 public final AlwaysOnHotwordDetector createAlwaysOnHotwordDetector( 231 String keyphrase, Locale locale, AlwaysOnHotwordDetector.Callback callback) { 232 if (mSystemService == null) { 233 throw new IllegalStateException("Not available until onReady() is called"); 234 } 235 synchronized (mLock) { 236 // Allow only one concurrent recognition via the APIs. 237 safelyShutdownHotwordDetector(); 238 mHotwordDetector = new AlwaysOnHotwordDetector(keyphrase, locale, callback, 239 mKeyphraseEnrollmentInfo, mInterface, mSystemService); 240 } 241 return mHotwordDetector; 242 } 243 244 /** 245 * @return Details of keyphrases available for enrollment. 246 * @hide 247 */ 248 @VisibleForTesting 249 protected final KeyphraseEnrollmentInfo getKeyphraseEnrollmentInfo() { 250 return mKeyphraseEnrollmentInfo; 251 } 252 253 private void safelyShutdownHotwordDetector() { 254 try { 255 synchronized (mLock) { 256 if (mHotwordDetector != null) { 257 mHotwordDetector.stopRecognition(); 258 mHotwordDetector.invalidate(); 259 mHotwordDetector = null; 260 } 261 } 262 } catch (Exception ex) { 263 // Ignore. 264 } 265 } 266 267 @Override 268 protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) { 269 pw.println("VOICE INTERACTION"); 270 synchronized (mLock) { 271 pw.println(" AlwaysOnHotwordDetector"); 272 if (mHotwordDetector == null) { 273 pw.println(" NULL"); 274 } else { 275 mHotwordDetector.dump(" ", pw); 276 } 277 } 278 } 279} 280