Java tutorial
package com.bellman.bible.service.device.speak; import android.content.Context; import android.speech.tts.TextToSpeech; import android.util.Log; import com.bellman.bible.android.activity.R; import com.bellman.bible.android.control.event.ABEventBus; import com.bellman.bible.android.control.event.phonecall.PhoneCallMonitor; import com.bellman.bible.android.control.event.phonecall.PhoneCallStarted; import com.bellman.bible.android.view.activity.base.CurrentActivityHolder; import com.bellman.bible.android.view.activity.base.Dialogs; import com.bellman.bible.service.common.CommonUtils; import com.bellman.bible.service.device.speak.event.SpeakEvent; import com.bellman.bible.service.device.speak.event.SpeakEvent.SpeakState; import com.bellman.bible.service.device.speak.event.SpeakEventManager; import org.apache.commons.lang3.StringUtils; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Locale; import de.greenrobot.event.EventBus; /** * <p>text-to-speech (TTS). Please note the following steps:</p> * <p> * <ol> * <li>Construct the TextToSpeech object.</li> * <li>Handle initialization callback in the onInit method. * The activity implements TextToSpeech.OnInitListener for this purpose.</li> * <li>Call TextToSpeech.speak to synthesize speech.</li> * <li>Shutdown TextToSpeech in onDestroy.</li> * </ol> * <p> * <p>Documentation: * http://developer.android.com/reference/android/speech/tts/package-summary.html * </p> * <ul> * * @author Martin Denham [mjdenham at gmail dot com] * @see gnu.lgpl.License for license details.<br> * The copyright to this program is held by it's author. */ public class TextToSpeechController implements TextToSpeech.OnInitListener, TextToSpeech.OnUtteranceCompletedListener { private static final String TAG = "Speak"; private static final String UTTERANCE_PREFIX = "AND-BIBLE-"; private static final TextToSpeechController singleton = new TextToSpeechController(); private static String PERSIST_LOCALE_KEY = "SpeakLocale"; private TextToSpeech mTts; private List<Locale> localePreferenceList; private Locale currentLocale = Locale.getDefault(); private SpeakTextProvider mSpeakTextProvider; private SpeakTiming mSpeakTiming; private TTSLanguageSupport ttsLanguageSupport = new TTSLanguageSupport(); private SpeakEventManager speakEventManager = SpeakEventManager.getInstance(); private Context context; private long uniqueUtteranceNo = 0; // tts.isSpeaking() returns false when multiple text is queued on some older versions of Android so maintain it manually private boolean isSpeaking = false; private boolean isPaused = false; private TextToSpeechController() { Log.d(TAG, "Creating TextToSpeechController"); context = CurrentActivityHolder.getInstance().getApplication().getApplicationContext(); mSpeakTextProvider = new SpeakTextProvider(); mSpeakTiming = new SpeakTiming(); restorePauseState(); } public static TextToSpeechController getInstance() { return singleton; } public boolean isLanguageAvailable(String langCode) { return ttsLanguageSupport.isLangKnownToBeSupported(langCode); } public synchronized void speak(List<Locale> localePreferenceList, List<String> textToSpeak, boolean queue) { Log.d(TAG, "speak strings" + (queue ? " queued" : "")); if (!queue) { Log.d(TAG, "Queue is false so requesting stop"); clearTtsQueue(); } else if (isPaused()) { Log.d(TAG, "New speak request while paused so clearing paused speech"); clearTtsQueue(); isPaused = false; } mSpeakTextProvider.addTextsToSpeak(textToSpeak); // currently can't change Locale until speech ends this.localePreferenceList = localePreferenceList; startSpeakingInitingIfRequired(); } private void startSpeakingInitingIfRequired() { if (mTts == null) { Log.d(TAG, "mTts was null so initialising Tts"); try { // Initialize text-to-speech. This is an asynchronous operation. // The OnInitListener (second argument) is called after initialization completes. mTts = new TextToSpeech(context, this // TextToSpeech.OnInitListener ); } catch (Exception e) { Log.e(TAG, "Error initialising Tts", e); showError(R.string.error_occurred, e); } } else { startSpeaking(); } } // Implements TextToSpeech.OnInitListener. @Override public void onInit(int status) { Log.d(TAG, "Tts initialised"); boolean isOk = false; // status can be either TextToSpeech.SUCCESS or TextToSpeech.ERROR. if (mTts != null && status == TextToSpeech.SUCCESS) { Log.d(TAG, "Tts initialisation succeeded"); boolean localeOK = false; Locale locale = null; for (int i = 0; i < localePreferenceList.size() && !localeOK; i++) { locale = localePreferenceList.get(i); Log.d(TAG, "Checking for locale:" + locale); int result = mTts.setLanguage(locale); localeOK = ((result != TextToSpeech.LANG_MISSING_DATA) && (result != TextToSpeech.LANG_NOT_SUPPORTED)); if (localeOK) { Log.d(TAG, "Successful locale:" + locale); currentLocale = locale; } } if (!localeOK) { Log.e(TAG, "TTS missing or not supported"); // Language data is missing or the language is not supported. ttsLanguageSupport.addUnsupportedLocale(locale); showError(R.string.tts_lang_not_available, new Exception("Tts missing or not supported")); } else { // The TTS engine has been successfully initialized. ttsLanguageSupport.addSupportedLocale(locale); int ok = mTts.setOnUtteranceCompletedListener(this); if (ok == TextToSpeech.ERROR) { Log.e(TAG, "Error registering onUtteranceCompletedListener"); } else { // everything seems to have succeeded if we get here isOk = true; // say the text startSpeaking(); // add event listener to stop on call stopIfPhoneCall(); } } } else { Log.d(TAG, "Tts initialisation failed"); // Initialization failed. showError(R.string.error_occurred, new Exception("Tts Initialisation failed")); } if (!isOk) { shutdown(); } } /** * Add event listener to stop on call */ protected void stopIfPhoneCall() { PhoneCallMonitor.ensureMonitoringStarted(); // listen for phone call in order to pause speak ABEventBus.getDefault().safelyRegister(this); } public synchronized void rewind() { Log.d(TAG, "Rewind TTS"); // prevent onUtteranceCompleted causing next text to be grabbed uniqueUtteranceNo++; boolean wasPaused = isPaused; isPaused = true; if (isSpeaking) { mTts.stop(); } isSpeaking = false; if (!wasPaused) { // ensure current position is saved which is done during pause mSpeakTextProvider.pause(mSpeakTiming.getFractionCompleted()); } // move current position back a bit mSpeakTextProvider.rewind(); isPaused = wasPaused; if (!isPaused) { startSpeakingInitingIfRequired(); } } public synchronized void forward() { Log.d(TAG, "Forward TTS"); // prevent onUtteranceCompleted causing next text to be grabbed uniqueUtteranceNo++; boolean wasPaused = isPaused; isPaused = true; if (isSpeaking) { mTts.stop(); } isSpeaking = false; if (!wasPaused) { // ensure current position is saved which is done during pause mSpeakTextProvider.pause(mSpeakTiming.getFractionCompleted()); } // move current position back a bit mSpeakTextProvider.forward(); isPaused = wasPaused; if (!isPaused) { startSpeakingInitingIfRequired(); } } public synchronized void pause() { Log.d(TAG, "Pause TTS"); if (isSpeaking()) { isPaused = true; isSpeaking = false; mSpeakTextProvider.pause(mSpeakTiming.getFractionCompleted()); //kill the tts engine because it could be a long ime before restart and the engine may become corrupted or used elsewhere shutdownTtsEngine(); fireStateChangeEvent(); } } public synchronized void continueAfterPause() { try { Log.d(TAG, "continue after pause"); isPaused = false; // ask TTs to say the text startSpeakingInitingIfRequired(); } catch (Exception e) { Log.e(TAG, "TTS Error continuing after Pause", e); mSpeakTextProvider.reset(); isSpeaking = false; shutdown(); } // should be able to clear this because we are now speaking isPaused = false; } /** * only check timing when paused to prevent concurrency problems */ public long getPausedTotalSeconds() { return mSpeakTiming.getSecsForChars(mSpeakTextProvider.getTotalChars()); } public long getPausedCompletedSeconds() { return mSpeakTiming.getSecsForChars(mSpeakTextProvider.getSpokenChars()); } private void startSpeaking() { Log.d(TAG, "about to send all text to TTS"); // ask TTs to say the text if (!isSpeaking) { speakNextChunk(); isSpeaking = true; isPaused = false; fireStateChangeEvent(); } // should be able to clear this because we are now speaking isPaused = false; } @Override public void onUtteranceCompleted(String utteranceId) { Log.d(TAG, "onUtteranceCompleted:" + utteranceId); // pause/rew/ff can sometimes allow old messages to complete so need to prevent move to next sentence if completed utterance is out of date if ((!isPaused && isSpeaking) && StringUtils.startsWith(utteranceId, UTTERANCE_PREFIX)) { long utteranceNo = Long.valueOf(StringUtils.removeStart(utteranceId, UTTERANCE_PREFIX)); if (utteranceNo == uniqueUtteranceNo - 1) { mSpeakTextProvider.finishedUtterance(utteranceId); // estimate cps mSpeakTiming.finished(utteranceId); // ask TTs to say the text if (mSpeakTextProvider.isMoreTextToSpeak()) { speakNextChunk(); } else { Log.d(TAG, "Shutting down TTS"); shutdown(); } } } } private void speakNextChunk() { String text = mSpeakTextProvider.getNextTextToSpeak(); if (text.length() > 0) { speakString(text); } } private void speakString(String text) { if (mTts == null) { Log.e(TAG, "Error: attempt to speak when tts is null. Text:" + text); } else { // Always set the UtteranceId (or else OnUtteranceCompleted will not be called) HashMap<String, String> dummyTTSParams = new HashMap<String, String>(); String utteranceId = UTTERANCE_PREFIX + uniqueUtteranceNo++; dummyTTSParams.put(TextToSpeech.Engine.KEY_PARAM_UTTERANCE_ID, utteranceId); Log.d(TAG, "do speak substring of length:" + text.length() + " utteranceId:" + utteranceId); mTts.speak(text, TextToSpeech.QUEUE_ADD, // handle flush by clearing text queue dummyTTSParams); mSpeakTiming.started(utteranceId, text.length()); isSpeaking = true; // Log.d(TAG, "Speaking:"+text); } } /** * flush cached text */ private void clearTtsQueue() { Log.d(TAG, "Stop TTS"); // Don't forget to shutdown! if (isSpeaking()) { Log.d(TAG, "Flushing speech"); // flush remaining text mTts.speak(" ", TextToSpeech.QUEUE_FLUSH, null); } mSpeakTextProvider.reset(); isSpeaking = false; } private void showError(int msgId, Exception e) { Dialogs.getInstance().showErrorMsg(msgId); } public void shutdown() { Log.d(TAG, "Shutdown TTS"); isSpeaking = false; isPaused = false; // tts.stop can trigger onUtteranceCompleted so set above flags first to avoid sending of a further text and setting isSpeaking to true shutdownTtsEngine(); mSpeakTextProvider.reset(); fireStateChangeEvent(); } private void shutdownTtsEngine() { Log.d(TAG, "Shutdown TTS Engine"); try { // Don't forget to shutdown! if (mTts != null) { try { mTts.stop(); } catch (Exception e) { Log.e(TAG, "Error stopping Tts engine", e); } mTts.shutdown(); // de-register from EventBus EventBus.getDefault().unregister(this); } } catch (Exception e) { Log.e(TAG, "Error shutting down Tts engine", e); } finally { mTts = null; } } private void fireStateChangeEvent() { if (isPaused) { speakEventManager.speakStateChanged(new SpeakEvent(SpeakState.PAUSED)); } else if (isSpeaking) { speakEventManager.speakStateChanged(new SpeakEvent(SpeakState.SPEAKING)); } else { speakEventManager.speakStateChanged(new SpeakEvent(SpeakState.SILENT)); } } public boolean isSpeaking() { return isSpeaking; } public boolean isPaused() { return isPaused; } /** * Pause speak if phone call starts */ public void onEvent(PhoneCallStarted event) { if (isSpeaking()) { pause(); } if (isPaused()) { persistPauseState(); } else { // ensure a previous pause does not hang around and be restored incorrectly clearPauseState(); } shutdownTtsEngine(); } /** * persist and restore pause state to allow pauses to continue over an app exit */ private void persistPauseState() { Log.d(TAG, "Persisting Pause state"); mSpeakTextProvider.persistState(); CommonUtils.getSharedPreferences().edit().putString(PERSIST_LOCALE_KEY, currentLocale.toString()).commit(); } private void restorePauseState() { // ensure no relevant current state is overwritten accidentally if (!isSpeaking() && !isPaused()) { Log.d(TAG, "Attempting to restore any Persisted Pause state"); isPaused = mSpeakTextProvider.restoreState(); // restore locale information so tts knows which voice to load when it initialises currentLocale = new Locale(CommonUtils.getSharedPreferences().getString(PERSIST_LOCALE_KEY, Locale.getDefault().toString())); localePreferenceList = new ArrayList<Locale>(); localePreferenceList.add(currentLocale); } } private void clearPauseState() { Log.d(TAG, "Clearing Persisted Pause state"); mSpeakTextProvider.clearPersistedState(); CommonUtils.getSharedPreferences().edit().remove(PERSIST_LOCALE_KEY).commit(); } }