Changes to use audio focus for TTS engine.

OsmAnd/src/net/osmand/plus/voice/AbstractPrologCommandPlayer.java

@@ -28,12 +28,13 @@ import alice.tuprolog.Struct;
 import alice.tuprolog.Term;
 import alice.tuprolog.Theory;
 import alice.tuprolog.Var;
+import android.annotation.SuppressLint;
 import android.content.Context;
+import android.media.AudioManager;
 
 public abstract class AbstractPrologCommandPlayer implements CommandPlayer {
 
-	private static final Log log = LogUtil
+	private static final Log log = LogUtil.getLog(AbstractPrologCommandPlayer.class);
-			.getLog(AbstractPrologCommandPlayer.class);
 
 	protected Context ctx;
 	protected File voiceDir;
@@ -51,10 +52,14 @@ public abstract class AbstractPrologCommandPlayer implements CommandPlayer {
 	protected static final String DELAY_CONST = "delay_";
 	/** Must be sorted array! */
 	private final int[] sortedVoiceVersions;
+	private AudioFocusHelper mAudioFocusHelper;
+
+	private int streamType;
 
 	protected AbstractPrologCommandPlayer(Context ctx, OsmandSettings settings, String voiceProvider, String configFile, int[] sortedVoiceVersions)
 		throws CommandPlayerException 
 	{
+		this.ctx = ctx;
 		this.sortedVoiceVersions = sortedVoiceVersions;
 		long time = System.currentTimeMillis();
 		try {
@@ -67,6 +72,7 @@ public abstract class AbstractPrologCommandPlayer implements CommandPlayer {
 		if (log.isInfoEnabled()) {
 			log.info("Initializing prolog system : " + (System.currentTimeMillis() - time)); //$NON-NLS-1$
 		}
+		this.streamType = settings.AUDIO_STREAM_GUIDANCE.get();  
 		init(voiceProvider, settings, configFile);
 	}
 	
@@ -189,4 +195,59 @@ public abstract class AbstractPrologCommandPlayer implements CommandPlayer {
 		prologSystem = null;
 	}
 
+	@Override
+	public void updateAudioStream(int streamType) {
+		this.streamType = streamType;
+	}
+	
+	protected void requestAudioFocus() {
+		log.debug("requestAudioFocus");
+		if (android.os.Build.VERSION.SDK_INT >= 8) {
+		    mAudioFocusHelper = new AudioFocusHelper(ctx);
+		}
+		if (mAudioFocusHelper != null)
+			mAudioFocusHelper.requestFocus();
+	}
+	
+	protected void abandonAudioFocus() {
+		log.debug("abandonAudioFocus");
+		if (mAudioFocusHelper != null) {
+			mAudioFocusHelper.abandonFocus();
+			mAudioFocusHelper = null;
+		}
+	}
+
+	/**
+	 * This helper class allows API level 8 calls to be isolated from the rest of the app.
+	 * This class is only be instantiated on OS versions which support it. 
+	 * @author genly
+	 *
+	 */
+	// We Use API level 8 calls here, suppress warnings.
+	@SuppressLint("NewApi")
+    public class AudioFocusHelper implements AudioManager.OnAudioFocusChangeListener {
+		private Context mContext;
+		private AudioManager mAudioManager;
+
+		public AudioFocusHelper(Context context) {
+			mContext = context;
+			mAudioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
+		}
+		
+		public boolean requestFocus() {
+			return AudioManager.AUDIOFOCUS_REQUEST_GRANTED ==
+					mAudioManager.requestAudioFocus(this, streamType, AudioManager.AUDIOFOCUS_GAIN_TRANSIENT);
+		}
+
+		public boolean abandonFocus() {
+			return AudioManager.AUDIOFOCUS_REQUEST_GRANTED == mAudioManager.abandonAudioFocus(this);
+		}
+	    @Override
+	    public void onAudioFocusChange(int focusChange) {
+	    	// Basically we ignore audio focus changes.  There's not much we can do when we have interrupted audio
+	    	// for our speech, and we in turn get interrupted.  Ignore it until a scenario comes up which gives us
+	    	// reason to change this strategy.
+	    	log.error("MediaCommandPlayerImpl.onAudioFocusChange(): Unexpected audio focus change: "+focusChange);
+	    }
+	}
 }

OsmAnd/src/net/osmand/plus/voice/MediaCommandPlayerImpl.java

@@ -11,11 +11,10 @@ import net.osmand.plus.OsmandSettings;
 
 import org.apache.commons.logging.Log;
 
-import android.annotation.SuppressLint;
 import android.content.Context;
-import android.media.AudioManager;
 import android.media.MediaPlayer;
 
+
 /**
  * That class represents command player. 
  * It gets commands from input, analyze what files should be played and play 
@@ -33,21 +32,12 @@ public class MediaCommandPlayerImpl extends AbstractPrologCommandPlayer implemen
 	// indicates that player is ready to play first file
 	private List<String> filesToPlay = Collections.synchronizedList(new ArrayList<String>());
 	private int streamType;
-	private final Context mCtx;
-	private AudioFocusHelper mAudioFocusHelper;
 
 	
 	public MediaCommandPlayerImpl(Context ctx, OsmandSettings settings, String voiceProvider)
 		throws CommandPlayerException
 	{
 		super(ctx, settings, voiceProvider, CONFIG_FILE, MEDIA_VOICE_VERSION);
-		mCtx = ctx;
-		this.streamType = settings.AUDIO_STREAM_GUIDANCE.get();  
-	}
-	
-	@Override
-	public void updateAudioStream(int streamType) {
-		this.streamType = streamType;
 	}
 	
 	@Override
@@ -62,13 +52,7 @@ public class MediaCommandPlayerImpl extends AbstractPrologCommandPlayer implemen
 		
 		// If we have not already started to play audio, start.
 		if (mediaPlayer == null) {
-			if (android.os.Build.VERSION.SDK_INT >= 8) {
+			requestAudioFocus();
-			    mAudioFocusHelper = new AudioFocusHelper(mCtx);
-			} else {
-			    mAudioFocusHelper = null;
-			}
-			if (mAudioFocusHelper != null)
-				mAudioFocusHelper.requestFocus();
 			playQueue();
 		}
 	}
@@ -89,14 +73,17 @@ public class MediaCommandPlayerImpl extends AbstractPrologCommandPlayer implemen
 				mediaPlayer.release();
 				mediaPlayer = null;
 
-				if (mAudioFocusHelper != null)
+				abandonAudioFocus();
-					mAudioFocusHelper.abandonFocus();
 			}
 		}
 	}
 	
+	/**
+	 * Called when the MediaPlayer is done.
+	 */
 	@Override
 	public void onCompletion(MediaPlayer mp) {
+		// Work on the next file to play.
 		playQueue();
 	}
 
@@ -131,6 +118,11 @@ public class MediaCommandPlayerImpl extends AbstractPrologCommandPlayer implemen
 		return null;
 	}
 	
+	/**
+	 * Starts the MediaPlayer playing a file.  This method will return immediately.
+	 * OnCompletionListener() will be called when the MediaPlayer is done.
+	 * @param file
+	 */
 	private void playFile(File file)  {
 		log.debug("Playing file : " + file); //$NON-NLS-1$
 		try {
@@ -150,34 +142,4 @@ public class MediaCommandPlayerImpl extends AbstractPrologCommandPlayer implemen
 		return new File(voiceDir, CONFIG_FILE).exists();
 	}
 	
-	/**
-	 * This helper class allows API level 8 calls to be isolated from the rest of the app.
-	 * This class is only be instantiated on OS versions which support it. 
-	 * @author genly
-	 *
-	 */
-	// We Use API level 8 calls here, suppress warnings.
-	@SuppressLint("NewApi")
-    public class AudioFocusHelper implements AudioManager.OnAudioFocusChangeListener {
-		private Context mContext;
-		private AudioManager mAudioManager;
-
-		public AudioFocusHelper(Context context) {
-			mContext = context;
-			mAudioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
-		}
-		
-		public boolean requestFocus() {
-			return AudioManager.AUDIOFOCUS_REQUEST_GRANTED ==
-					mAudioManager.requestAudioFocus(this, streamType, AudioManager.AUDIOFOCUS_GAIN_TRANSIENT);
-		}
-
-		public boolean abandonFocus() {
-			return AudioManager.AUDIOFOCUS_REQUEST_GRANTED == mAudioManager.abandonAudioFocus(this);
-		}
-	    @Override
-	    public void onAudioFocusChange(int focusChange) {
-	    		log.error("MediaCommandPlayerImpl.onAudioFocusChange(): Unexpected audio focus change: "+focusChange);
-	    }
-	}
 }

OsmAnd/src/net/osmand/plus/voice/TTSCommandPlayerImpl.java

@@ -5,7 +5,10 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 
+import org.apache.commons.logging.Log;
+
 import net.osmand.Algoritms;
+import net.osmand.LogUtil;
 import net.osmand.plus.OsmandApplication;
 import net.osmand.plus.OsmandSettings;
 import net.osmand.plus.R;
@@ -21,6 +24,7 @@ import android.content.Intent;
 import android.net.Uri;
 import android.speech.tts.TextToSpeech;
 import android.speech.tts.TextToSpeech.OnInitListener;
+import android.speech.tts.TextToSpeech.OnUtteranceCompletedListener;
 
 public class TTSCommandPlayerImpl extends AbstractPrologCommandPlayer {
 
@@ -53,6 +57,7 @@ public class TTSCommandPlayerImpl extends AbstractPrologCommandPlayer {
 
 	private static final String CONFIG_FILE = "_ttsconfig.p";
 	private static final int[] TTS_VOICE_VERSION = new int[] { 100, 101 }; // !! MUST BE SORTED
+	private static final Log log = LogUtil.getLog(TTSCommandPlayerImpl.class);
 	private TextToSpeech mTts;
 	private Context mTtsContext;
 	private String language;
@@ -76,6 +81,15 @@ public class TTSCommandPlayerImpl extends AbstractPrologCommandPlayer {
 	
 	
 
+	/**
+	 * Since TTS requests are asynchronous, playCommands() can be called before
+	 * the TTS engine is done. We use this field to keep track of concurrent tts
+	 * activity. Where tts activity is defined as the time between tts.speak()
+	 * and the call back to onUtteranceCompletedListener().  This allows us to
+	 * optimize use of requesting and abandoning audio focus.
+	 */
+	private int ttsRequests;
+	
 	@Override
 	public void playCommands(CommandBuilder builder) {
 		if (mTts != null) {
@@ -84,7 +98,11 @@ public class TTSCommandPlayerImpl extends AbstractPrologCommandPlayer {
 			for (String s : execute) {
 				bld.append(s).append(' ');
 			}
+			if (ttsRequests++ == 0)
+				requestAudioFocus();
+			log.debug("ttsRequests="+ttsRequests);
 			mTts.speak(bld.toString(), TextToSpeech.QUEUE_ADD, params);
+			// Audio focus will be released when onUtteranceCompleted() completed is called by the TTS engine.
 		}
 	}
 
@@ -141,6 +159,14 @@ public class TTSCommandPlayerImpl extends AbstractPrologCommandPlayer {
 					return ctx instanceof SettingsActivity;
 				}
 			});
+			mTts.setOnUtteranceCompletedListener(new OnUtteranceCompletedListener() {
+				@Override
+				public void onUtteranceCompleted(String utteranceId) {
+					if (--ttsRequests == 0)
+						abandonAudioFocus();
+					log.debug("ttsRequests="+ttsRequests);
+				}
+			});
 		}
 	}
 	
@@ -175,6 +201,7 @@ public class TTSCommandPlayerImpl extends AbstractPrologCommandPlayer {
 
 	@Override
 	public void updateAudioStream(int streamType) {
+		super.updateAudioStream(streamType);
 		params.put(TextToSpeech.Engine.KEY_PARAM_STREAM, streamType+"");		
 	}