Google應用程式中的Google Text-To-Speech API

Question

我想在Android應用程序中使用Google的語音轉換API，但是我只能從Web（Chrome）找到解決方法。 這是我第一次嘗試通過該應用播放“ Hello world”。

playTTS是onClick，已執行，但沒有聲音播放。 我需要導入任何JS / Java庫嗎？ 是否可以從中生成音頻文件？

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    myBrowser = new WebView(this);
    if (savedInstanceState == null) {
        getSupportFragmentManager().beginTransaction()
                .add(R.id.container, new PlaceholderFragment()).commit();
    }
}

public void playTTS(View view) {
    myBrowser.loadUrl("javascript:speechSynthesis.speak(
         SpeechSynthesisUtterance('Hello World'))");
}

Answer 1

TTS代碼：

import android.annotation.TargetApi;
import android.content.Context;
import android.os.Build;
import android.speech.tts.TextToSpeech;
import android.speech.tts.UtteranceProgressListener;
import android.util.Log;
import android.webkit.JavascriptInterface;
import android.webkit.WebView;
import android.widget.Toast;

import java.util.HashMap;
import java.util.Locale;

public class KiwixTextToSpeech {

    public static final String TAG_ASKQ = "askq;

    private Context context;

    private OnSpeakingListener onSpeakingListener;

    private WebView webView;

    private TextToSpeech tts;

    private boolean initialized = false;

    /**
     * Constructor.
     *
     * @param context               the context to create TextToSpeech with
     * @param webView               {@link android.webkit.WebView} to take contents from
     * @param onInitSucceedListener listener that receives event when initialization of TTS is done
     *                              (and does not receive if it failed)
     * @param onSpeakingListener    listener that receives an event when speaking just started or
     *                              ended
     */
    public KiwixTextToSpeech(Context context, WebView webView,
            final OnInitSucceedListener onInitSucceedListener,
            final OnSpeakingListener onSpeakingListener) {
        Log.d(TAG_ASKQ, "Initializing TextToSpeech");

        this.context = context;
        this.onSpeakingListener = onSpeakingListener;
        this.webView = webView;
        this.webView.addJavascriptInterface(new TTSJavaScriptInterface(), "tts");

        initTTS(onInitSucceedListener);
    }

    @TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1)
    private void initTTS(final OnInitSucceedListener onInitSucceedListener) {
        tts = new TextToSpeech(context, new TextToSpeech.OnInitListener() {
            @Override
            public void onInit(int status) {
                if (status == TextToSpeech.SUCCESS) {
                    Log.d(TAG_ASKQ, "TextToSpeech was initialized successfully.");
                    initialized = true;
                    onInitSucceedListener.onInitSucceed();
                } else {
                    Log.e(TAG_ASKQ, "Initilization of TextToSpeech Failed!");
                }
            }
        });

        tts.setOnUtteranceProgressListener(new UtteranceProgressListener() {
            @Override
            public void onStart(String utteranceId) {
            }

            @Override
            public void onDone(String utteranceId) {
                Log.e(TAG_ASKQ, "TextToSpeech: " + utteranceId);
                onSpeakingListener.onSpeakingEnded();
            }

            @Override
            public void onError(String utteranceId) {
                Log.e(TAG_ASKQ, "TextToSpeech: " + utteranceId);
                onSpeakingListener.onSpeakingEnded();
            }
        });
    }

    /**
     * Reads the currently selected text in the WebView.
     */
    public void readSelection() {
      webView.loadUrl("javascript:tts.speakAloud(window.getSelection().toString());", null);
    }

    /**
     * Starts speaking the WebView content aloud (or stops it if TTS is speaking now).
     */
    public void readAloud() {
        if (tts.isSpeaking()) {
            if (tts.stop() == TextToSpeech.SUCCESS) {
                onSpeakingListener.onSpeakingEnded();
            }
        } else {
            Locale locale = LanguageUtils.ISO3ToLocale(ZimContentProvider.getLanguage());
            int result;
            if (locale == null
                    || (result = tts.isLanguageAvailable(locale)) == TextToSpeech.LANG_MISSING_DATA
                    || result == TextToSpeech.LANG_NOT_SUPPORTED) {
                Log.d(TAG_ASKQ, "TextToSpeech: language not supported: " +
                        ZimContentProvider.getLanguage() + " (" + locale.getLanguage() + ")");
                Toast.makeText(context,
                        context.getResources().getString(R.string.tts_lang_not_supported),
                        Toast.LENGTH_LONG).show();
            } else {
                tts.setLanguage(locale);

                // We use JavaScript to get the content of the page conveniently, earlier making some
                // changes in the page
                webView.loadUrl("javascript:" +
                        "body = document.getElementsByTagName('body')[0].cloneNode(true);" +
                        // Remove some elements that are shouldn't be read (table of contents,
                        // references numbers, thumbnail captions, duplicated title, etc.)
                        "toRemove = body.querySelectorAll('sup.reference, #toc, .thumbcaption, " +
                        "    title, .navbox');" +
                        "Array.prototype.forEach.call(toRemove, function(elem) {" +
                        "    elem.parentElement.removeChild(elem);" +
                        "});" +
                        "tts.speakAloud(body.innerText);");
            }
        }
    }

    /**
     * Returns whether the TTS is initialized.
     *
     * @return <code>true</code> if TTS is initialized; <code>false</code> otherwise
     */
    public boolean isInitialized() {
        return initialized;
    }

    /**
     * Releases the resources used by the engine.
     *
     * @see android.speech.tts.TextToSpeech#shutdown()
     */
    public void shutdown() {
        tts.shutdown();
    }

    /**
     * The listener which is notified when initialization of the TextToSpeech engine is successfully
     * done.
     */
    public interface OnInitSucceedListener {

        public void onInitSucceed();
    }

    /**
     * The listener that is notified when speaking starts or stops (regardless of whether it was a
     * result of error, user, or because whole text was read).
     *
     * Note that the methods of this interface may not be called from the UI thread.
     */
    public interface OnSpeakingListener {

        public void onSpeakingStarted();

        public void onSpeakingEnded();
    }

    private class TTSJavaScriptInterface {

        @JavascriptInterface
        @SuppressWarnings("unused")
        public void speakAloud(String content) {
            String[] lines = content.split("\n");
            for (int i = 0; i < lines.length - 1; i++) {
                String line = lines[i];
                tts.speak(line, TextToSpeech.QUEUE_ADD, null);
            }

            HashMap<String, String> params = new HashMap<>();
            // The utterance ID isn't actually used anywhere, the param is passed only to force
            // the utterance listener to be notified
            params.put(TextToSpeech.Engine.KEY_PARAM_UTTERANCE_ID, "kiwixLastMessage");
            tts.speak(lines[lines.length - 1], TextToSpeech.QUEUE_ADD, params);

            if (lines.length > 0) {
                onSpeakingListener.onSpeakingStarted();
            }
        }
    }
}

Answer 2

在Android Java代碼中，您的Activity / other類應實現TextToSpeech.OnInitListener 。 您將通過調用TextToSpeech(context, this)獲得一個TextToSpeech實例。 （凡context指的是應用程序的上下文-可this在一個活動。）然后，您將收到onInit()以回調status ，它告訴TTS引擎是否可用。

您可以通過調用tts.speak(textToBeSpoken, TextToSpeech.QUEUE_FLUSH, null)或tts.speak(textToBeSpoken, TextToSpeech.QUEUE_ADD, null) 。 第一個會打斷仍在說的任何“話語”，而后一個會把新的“話語”添加到隊列中。 最后一個參數不是必需的。 如果您想通過設置UtteranceProgressListener來監視TTS狀態，則可能是您定義的“話語ID”。 （不必要）

在Java代碼中，一個簡單的“ TTS對話者”類可能類似於：

public class MyTtsTalker implements TextToSpeech.OnInitListener {

  private TextToSpeech tts;
  private boolean ttsOk;

  // The constructor will create a TextToSpeech instance.
  MyTtsTalker(Context context) {
    tts = new TextToSpeech(context, this);
  }

  @Override
  // OnInitListener method to receive the TTS engine status
  public void onInit(int status) {
    if (status == TextToSpeech.SUCCESS) {
      ttsOk = true;
    }
    else {
      ttsOk = false;
    }
  }

  // A method to speak something
  @SuppressWarnings("deprecation") // Support older API levels too.
  public void speak(String text, Boolean override) {
    if (ttsOk) {
      if (override) {
        tts.speak(text, TextToSpeech.QUEUE_FLUSH, null);    
      }    
      else {
        tts.speak(text, TextToSpeech.QUEUE_ADD, null);    
      }
    }
  }
}