how to Convert Text to Speech in Android

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="vertical"
   android:background="#345" >
 
<TextView android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="Text To Speech"
   android:padding="15dip"
   android:textColor="#0587d9"
   android:textSize="26dip"
   android:gravity="center"
   android:textStyle="bold"/>
 
<EditText android:id="@+id/txtText"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:hint="Enter some text to speak"
   android:layout_marginTop="20dip"
   android:layout_margin="10dip"/>
 
<Button android:id="@+id/btnSpeak"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="Speak Out"
   android:layout_margin="10dip"/>
</LinearLayout>

MainActivity.java

import java.util.Locale;
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 android.widget.EditText;
import android.widget.Toast;

public class AndroidTextToSpeechActivity extends Activity implements TextToSpeech.OnInitListener {
  private int result=0;
  private TextToSpeech tts;
  private Button btnSpeak;
  private EditText txtText;
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    tts = new TextToSpeech(this, this);
    btnSpeak = (Button)findViewById(R.id.btnSpeak);
    txtText = (EditText)findViewById(R.id.txtText);
    //button on click event
    btnSpeak.setOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View arg0) {
          speakOut();
        }
    });
  }
  //shutdown tts when activity destroy
  @Override
  public void onDestroy() {
  // Don't forget to shutdown!
  if (tts != null) {
    tts.stop();
    tts.shutdown();
   }
   super.onDestroy();
  }
  //It will called before TTS started
  @Override
  public void onInit(int status) {
  // TODO Auto-generated method stub
  //check status for TTS is initialized or not
  if (status == TextToSpeech.SUCCESS) {
  //if TTS initialized than set language
  result = tts.setLanguage(Locale.US);

  // tts.setPitch(5); // you can set pitch level
  // tts.setSpeechRate(2); //you can set speech speed rate

  //check language is supported or not
  //check language data is available or not
 if (result == TextToSpeech.LANG_MISSING_DATA || result == TextToSpeech.LANG_NOT_SUPPORTED) {
   Toast.makeText(this, "Missing data", Toast.LENGTH_LONG).show();
   //disable button
   btnSpeak.setEnabled(false);
  } else {
   //if all is good than enable button convert text to speech
   btnSpeak.setEnabled(true);
   }
  } else {
      Log.e("TTS", "Initilization Failed");
     }
  }
  //call this method to speak text
  private void speakOut() {
  String text = txtText.getText().toString();
  if(result!=tts.setLanguage(Locale.US))
  {
  Toast.makeText(getApplicationContext(), "Enter right Words...... ", Toast.LENGTH_LONG).show();
  }else
   {
    //speak given text
    tts.speak(text, TextToSpeech.QUEUE_FLUSH, null);
   }
  }
}