2 * Copyright (C) 2014 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 package android.service.voice;
19 import android.annotation.SdkConstant;
20 import android.app.Service;
21 import android.content.ComponentName;
22 import android.content.Context;
23 import android.content.Intent;
24 import android.hardware.soundtrigger.KeyphraseEnrollmentInfo;
25 import android.os.Bundle;
26 import android.os.Handler;
27 import android.os.IBinder;
28 import android.os.Message;
29 import android.os.RemoteException;
30 import android.os.ServiceManager;
31 import android.provider.Settings;
33 import com.android.internal.annotations.VisibleForTesting;
34 import com.android.internal.app.IVoiceInteractionManagerService;
38 * Top-level service of the current global voice interactor, which is providing
39 * support for hotwording, the back-end of a {@link android.app.VoiceInteractor}, etc.
40 * The current VoiceInteractionService that has been selected by the user is kept
41 * always running by the system, to allow it to do things like listen for hotwords
42 * in the background to instigate voice interactions.
44 * <p>Because this service is always running, it should be kept as lightweight as
45 * possible. Heavy-weight operations (including showing UI) should be implemented
46 * in the associated {@link android.service.voice.VoiceInteractionSessionService} when
47 * an actual voice interaction is taking place, and that service should run in a
48 * separate process from this one.
50 public class VoiceInteractionService extends Service {
52 * The {@link Intent} that must be declared as handled by the service.
53 * To be supported, the service must also require the
54 * {@link android.Manifest.permission#BIND_VOICE_INTERACTION} permission so
55 * that other applications can not abuse it.
57 @SdkConstant(SdkConstant.SdkConstantType.SERVICE_ACTION)
58 public static final String SERVICE_INTERFACE =
59 "android.service.voice.VoiceInteractionService";
62 * Name under which a VoiceInteractionService component publishes information about itself.
63 * This meta-data should reference an XML resource containing a
65 * android.R.styleable#VoiceInteractionService voice-interaction-service}></code> tag.
67 public static final String SERVICE_META_DATA = "android.voice_interaction";
69 IVoiceInteractionService mInterface = new IVoiceInteractionService.Stub() {
70 @Override public void ready() {
71 mHandler.sendEmptyMessage(MSG_READY);
73 @Override public void shutdown() {
74 mHandler.sendEmptyMessage(MSG_SHUTDOWN);
76 @Override public void soundModelsChanged() {
77 mHandler.sendEmptyMessage(MSG_SOUND_MODELS_CHANGED);
83 IVoiceInteractionManagerService mSystemService;
85 private final Object mLock = new Object();
87 private KeyphraseEnrollmentInfo mKeyphraseEnrollmentInfo;
89 private AlwaysOnHotwordDetector mHotwordDetector;
91 static final int MSG_READY = 1;
92 static final int MSG_SHUTDOWN = 2;
93 static final int MSG_SOUND_MODELS_CHANGED = 3;
95 class MyHandler extends Handler {
97 public void handleMessage(Message msg) {
103 onShutdownInternal();
105 case MSG_SOUND_MODELS_CHANGED:
106 onSoundModelsChangedInternal();
109 super.handleMessage(msg);
115 * Check whether the given service component is the currently active
116 * VoiceInteractionService.
118 public static boolean isActiveService(Context context, ComponentName service) {
119 String cur = Settings.Secure.getString(context.getContentResolver(),
120 Settings.Secure.VOICE_INTERACTION_SERVICE);
121 if (cur == null || cur.isEmpty()) {
124 ComponentName curComp = ComponentName.unflattenFromString(cur);
125 if (curComp == null) {
128 return curComp.equals(cur);
132 * Initiate the execution of a new {@link android.service.voice.VoiceInteractionSession}.
133 * @param args Arbitrary arguments that will be propagated to the session.
135 public void startSession(Bundle args) {
136 if (mSystemService == null) {
137 throw new IllegalStateException("Not available until onReady() is called");
140 mSystemService.startSession(mInterface, args);
141 } catch (RemoteException e) {
146 public void onCreate() {
148 mHandler = new MyHandler();
152 public IBinder onBind(Intent intent) {
153 if (SERVICE_INTERFACE.equals(intent.getAction())) {
154 return mInterface.asBinder();
160 * Called during service initialization to tell you when the system is ready
161 * to receive interaction from it. You should generally do initialization here
162 * rather than in {@link #onCreate()}. Methods such as {@link #startSession(Bundle)} and
163 * {@link #createAlwaysOnHotwordDetector(String, String, android.service.voice.AlwaysOnHotwordDetector.Callback)}
164 * will not be operational until this point.
166 public void onReady() {
167 mSystemService = IVoiceInteractionManagerService.Stub.asInterface(
168 ServiceManager.getService(Context.VOICE_INTERACTION_MANAGER_SERVICE));
169 mKeyphraseEnrollmentInfo = new KeyphraseEnrollmentInfo(getPackageManager());
172 private void onShutdownInternal() {
174 // Stop any active recognitions when shutting down.
175 // This ensures that if implementations forget to stop any active recognition,
176 // It's still guaranteed to have been stopped.
177 // This helps with cases where the voice interaction implementation is changed
179 safelyShutdownHotwordDetector();
183 * Called during service de-initialization to tell you when the system is shutting the
186 public void onShutdown() {
189 private void onSoundModelsChangedInternal() {
190 synchronized (this) {
191 if (mHotwordDetector != null) {
192 // TODO: Stop recognition if a sound model that was being recognized gets deleted.
193 mHotwordDetector.onSoundModelsChanged();
196 onSoundModelsChanged();
200 * Called when the sound models available for recognition change.
201 * This may be called if a new sound model is available or
202 * an existing one is updated or removed.
203 * Implementations must check the availability of the hotword detector if they own one
204 * by calling {@link AlwaysOnHotwordDetector#getAvailability()} before calling into it.
206 public void onSoundModelsChanged() {
210 * Creates an {@link AlwaysOnHotwordDetector} for the given keyphrase and locale.
211 * This instance must be retained and used by the client.
212 * Calling this a second time invalidates the previously created hotword detector
213 * which can no longer be used to manage recognition.
215 * @param keyphrase The keyphrase that's being used, for example "Hello Android".
216 * @param locale The locale for which the enrollment needs to be performed.
217 * This is a Java locale, for example "en_US".
218 * @param callback The callback to notify of detection events.
219 * @return An always-on hotword detector for the given keyphrase and locale.
221 public final AlwaysOnHotwordDetector createAlwaysOnHotwordDetector(
222 String keyphrase, String locale, AlwaysOnHotwordDetector.Callback callback) {
223 if (mSystemService == null) {
224 throw new IllegalStateException("Not available until onReady() is called");
226 synchronized (mLock) {
227 // Allow only one concurrent recognition via the APIs.
228 safelyShutdownHotwordDetector();
229 mHotwordDetector = new AlwaysOnHotwordDetector(keyphrase, locale, callback,
230 mKeyphraseEnrollmentInfo, mInterface, mSystemService);
232 return mHotwordDetector;
236 * @return Details of keyphrases available for enrollment.
240 protected final KeyphraseEnrollmentInfo getKeyphraseEnrollmentInfo() {
241 return mKeyphraseEnrollmentInfo;
244 private void safelyShutdownHotwordDetector() {
246 synchronized (mLock) {
247 if (mHotwordDetector != null) {
248 mHotwordDetector.stopRecognition();
249 mHotwordDetector.invalidate();
250 mHotwordDetector = null;
253 } catch (Exception ex) {