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      1  /*
      2  * Copyright (C) 2009 The Android Open Source Project
      3  *
      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
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     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.
     15  */
     16 
     17 package com.example.android.apis.app;
     18 
     19 import android.app.Activity;
     20 import android.os.Bundle;
     21 import android.speech.tts.TextToSpeech;
     22 import android.util.Log;
     23 import android.view.View;
     24 import android.widget.Button;
     25 
     26 import com.example.android.apis.R;
     27 
     28 import java.util.Locale;
     29 import java.util.Random;
     30 
     31 /**
     32  * <p>Demonstrates text-to-speech (TTS). Please note the following steps:</p>
     33  *
     34  * <ol>
     35  * <li>Construct the TextToSpeech object.</li>
     36  * <li>Handle initialization callback in the onInit method.
     37  * The activity implements TextToSpeech.OnInitListener for this purpose.</li>
     38  * <li>Call TextToSpeech.speak to synthesize speech.</li>
     39  * <li>Shutdown TextToSpeech in onDestroy.</li>
     40  * </ol>
     41  *
     42  * <p>Documentation:
     43  * http://developer.android.com/reference/android/speech/tts/package-summary.html
     44  * </p>
     45  * <ul>
     46  */
     47 public class TextToSpeechActivity extends Activity implements TextToSpeech.OnInitListener {
     48 
     49     private static final String TAG = "TextToSpeechDemo";
     50 
     51     private TextToSpeech mTts;
     52     private Button mAgainButton;
     53 
     54     @Override
     55     public void onCreate(Bundle savedInstanceState) {
     56         super.onCreate(savedInstanceState);
     57         setContentView(R.layout.text_to_speech);
     58 
     59         // Initialize text-to-speech. This is an asynchronous operation.
     60         // The OnInitListener (second argument) is called after initialization completes.
     61         mTts = new TextToSpeech(this,
     62             this  // TextToSpeech.OnInitListener
     63             );
     64 
     65         // The button is disabled in the layout.
     66         // It will be enabled upon initialization of the TTS engine.
     67         mAgainButton = (Button) findViewById(R.id.again_button);
     68 
     69         mAgainButton.setOnClickListener(new View.OnClickListener() {
     70             public void onClick(View v) {
     71                 sayHello();
     72             }
     73         });
     74     }
     75 
     76     @Override
     77     public void onDestroy() {
     78         // Don't forget to shutdown!
     79         if (mTts != null) {
     80             mTts.stop();
     81             mTts.shutdown();
     82         }
     83 
     84         super.onDestroy();
     85     }
     86 
     87     // Implements TextToSpeech.OnInitListener.
     88     public void onInit(int status) {
     89         // status can be either TextToSpeech.SUCCESS or TextToSpeech.ERROR.
     90         if (status == TextToSpeech.SUCCESS) {
     91             // Set preferred language to US english.
     92             // Note that a language may not be available, and the result will indicate this.
     93             int result = mTts.setLanguage(Locale.US);
     94             // Try this someday for some interesting results.
     95             // int result mTts.setLanguage(Locale.FRANCE);
     96             if (result == TextToSpeech.LANG_MISSING_DATA ||
     97                 result == TextToSpeech.LANG_NOT_SUPPORTED) {
     98                // Lanuage data is missing or the language is not supported.
     99                 Log.e(TAG, "Language is not available.");
    100             } else {
    101                 // Check the documentation for other possible result codes.
    102                 // For example, the language may be available for the locale,
    103                 // but not for the specified country and variant.
    104 
    105                 // The TTS engine has been successfully initialized.
    106                 // Allow the user to press the button for the app to speak again.
    107                 mAgainButton.setEnabled(true);
    108                 // Greet the user.
    109                 sayHello();
    110             }
    111         } else {
    112             // Initialization failed.
    113             Log.e(TAG, "Could not initialize TextToSpeech.");
    114         }
    115     }
    116 
    117     private static final Random RANDOM = new Random();
    118     private static final String[] HELLOS = {
    119       "Hello",
    120       "Salutations",
    121       "Greetings",
    122       "Howdy",
    123       "What's crack-a-lackin?",
    124       "That explains the stench!"
    125     };
    126 
    127     private void sayHello() {
    128         // Select a random hello.
    129         int helloLength = HELLOS.length;
    130         String hello = HELLOS[RANDOM.nextInt(helloLength)];
    131         mTts.speak(hello,
    132             TextToSpeech.QUEUE_FLUSH,  // Drop all pending entries in the playback queue.
    133             null);
    134     }
    135 
    136 }
    137