TextToSpeech_Sample

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:gravity="center">

    <Button
        android:id="@+id/action_read"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="読み上げ" />
</LinearLayout>

MainActivity.java

import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import java.util.Locale;

public class MainActivity extends AppCompatActivity implements TextToSpeech.OnInitListener {

    TextToSpeech tts;
    String contents = "読み上げたい内容";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        tts = new TextToSpeech(this, this);
        Button btn = (Button) findViewById(R.id.action_read);
        btn.setOnClickListener(new View.OnClickListener() {
            //ボタンクリック時
            public void onClick(View v) {
                if (v.getId() == R.id.action_read) {
                    speechText();
                }
            }
        });
    }

    @Override
    public void onInit(int status) {
        if (TextToSpeech.SUCCESS == status) {
            //言語選択
            Locale locale = Locale.JAPAN;
            if (tts.isLanguageAvailable(locale) >= TextToSpeech.LANG_AVAILABLE) {
                tts.setLanguage(locale);
            } else {
                Log.d("Error", "Locale");
            }
        } else {
            Log.d("Error", "Init");
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (null != tts) {
            //ttsのリソース解放する
            tts.shutdown();
        }
    }

    private void speechText() {
        if (0 < contents.length()) {
            if (tts.isSpeaking()) {
                // 読み上げ中なら停止
                tts.stop();
            }
            //読み上げられているテキストを確認
            System.out.println(contents);
            //読み上げ開始
            tts.speak(contents, TextToSpeech.QUEUE_FLUSH, null);
        }
    }
}