Android example source code file (TextToSpeechActivity.java)

This example Android source code file (TextToSpeechActivity.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

activity, android, button, could, greetings, hello, hellos, os, override, random, speech, string, tag, texttospeech, texttospeechactivity, texttospeechdemo, that, ui, util, utilities

The TextToSpeechActivity.java Android example source code

 /*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.apis.app;

import android.app.Activity;
import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.util.Log;
import android.view.View;
import android.widget.Button;

import com.example.android.apis.R;

import java.util.Locale;
import java.util.Random;

/**
 * <p>Demonstrates text-to-speech (TTS). Please note the following steps:

 *
 * <ol>
 * <li>Construct the TextToSpeech object.
 * <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>Shutdown TextToSpeech in onDestroy.
 * </ol>
 *
 * <p>Documentation:
 * http://developer.android.com/reference/android/speech/tts/package-summary.html
 * </p>
 * <ul>
 */
public class TextToSpeechActivity extends Activity implements TextToSpeech.OnInitListener {

    private static final String TAG = "TextToSpeechDemo";

    private TextToSpeech mTts;
    private Button mAgainButton;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.text_to_speech);

        // Initialize text-to-speech. This is an asynchronous operation.
        // The OnInitListener (second argument) is called after initialization completes.
        mTts = new TextToSpeech(this,
            this  // TextToSpeech.OnInitListener
            );

        // The button is disabled in the layout.
        // It will be enabled upon initialization of the TTS engine.
        mAgainButton = (Button) findViewById(R.id.again_button);

        mAgainButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                sayHello();
            }
        });
    }

    @Override
    public void onDestroy() {
        // Don't forget to shutdown!
        if (mTts != null) {
            mTts.stop();
            mTts.shutdown();
        }

        super.onDestroy();
    }

    // Implements TextToSpeech.OnInitListener.
    public void onInit(int status) {
        // status can be either TextToSpeech.SUCCESS or TextToSpeech.ERROR.
        if (status == TextToSpeech.SUCCESS) {
            // Set preferred language to US english.
            // Note that a language may not be available, and the result will indicate this.
            int result = mTts.setLanguage(Locale.US);
            // Try this someday for some interesting results.
            // int result mTts.setLanguage(Locale.FRANCE);
            if (result == TextToSpeech.LANG_MISSING_DATA ||
                result == TextToSpeech.LANG_NOT_SUPPORTED) {
               // Lanuage data is missing or the language is not supported.
                Log.e(TAG, "Language is not available.");
            } else {
                // Check the documentation for other possible result codes.
                // For example, the language may be available for the locale,
                // but not for the specified country and variant.

                // The TTS engine has been successfully initialized.
                // Allow the user to press the button for the app to speak again.
                mAgainButton.setEnabled(true);
                // Greet the user.
                sayHello();
            }
        } else {
            // Initialization failed.
            Log.e(TAG, "Could not initialize TextToSpeech.");
        }
    }

    private static final Random RANDOM = new Random();
    private static final String[] HELLOS = {
      "Hello",
      "Salutations",
      "Greetings",
      "Howdy",
      "What's crack-a-lackin?",
      "That explains the stench!"
    };

    private void sayHello() {
        // Select a random hello.
        int helloLength = HELLOS.length;
        String hello = HELLOS[RANDOM.nextInt(helloLength)];
        mTts.speak(hello,
            TextToSpeech.QUEUE_FLUSH,  // Drop all pending entries in the playback queue.
            null);
    }

}