android audio

package com.javacodegeeks.android.audiocapturetest;

import java.io.IOException;
import android.media.MediaPlayer;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

   private MediaRecorder myRecorder;
   private MediaPlayer myPlayer;
   private String outputFile = null;
   private Button startBtn;
   private Button stopBtn;
   private Button playBtn;
   private Button stopPlayBtn;
   private TextView text;
   
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      
      text = (TextView) findViewById(R.id.text1);
      // store it to sd card
      outputFile = Environment.getExternalStorageDirectory().
              getAbsolutePath() + "/javacodegeeksRecording.3gpp";

      myRecorder = new MediaRecorder();
      myRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
      myRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
      myRecorder.setAudioEncoder(MediaRecorder.OutputFormat.AMR_NB);
      myRecorder.setOutputFile(outputFile);
      
      startBtn = (Button)findViewById(R.id.start);
      startBtn.setOnClickListener(new OnClickListener() {
        
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            start(v);
        }
      });
      
      stopBtn = (Button)findViewById(R.id.stop);
      stopBtn.setOnClickListener(new OnClickListener() {
          
          @Override
          public void onClick(View v) {
              // TODO Auto-generated method stub
              stop(v);
          }
      });
      
      playBtn = (Button)findViewById(R.id.play);
      playBtn.setOnClickListener(new OnClickListener() {
          
          @Override
          public void onClick(View v) {
              // TODO Auto-generated method stub
                play(v);    
          }
      });
      
      stopPlayBtn = (Button)findViewById(R.id.stopPlay);
      stopPlayBtn.setOnClickListener(new OnClickListener() {
          
          @Override
          public void onClick(View v) {
              // TODO Auto-generated method stub
              stopPlay(v);
          }
      });
   }

   public void start(View view){
       try {
          myRecorder.prepare();
          myRecorder.start();
       } catch (IllegalStateException e) {
          // start:it is called before prepare()
          // prepare: it is called after start() or before setOutputFormat() 
          e.printStackTrace();
       } catch (IOException e) {
           // prepare() fails
           e.printStackTrace();
        }
       
       text.setText("Recording Point: Recording");
       startBtn.setEnabled(false);
       stopBtn.setEnabled(true);
       
       Toast.makeText(getApplicationContext(), "Start recording...", 
               Toast.LENGTH_SHORT).show();
   }

   public void stop(View view){
       try {
          myRecorder.stop();
          myRecorder.release();
          myRecorder  = null;
          
          stopBtn.setEnabled(false);
          playBtn.setEnabled(true);
          text.setText("Recording Point: Stop recording");
          
          Toast.makeText(getApplicationContext(), "Stop recording...",
                  Toast.LENGTH_SHORT).show();
       } catch (IllegalStateException e) {
            //  it is called before start()
            e.printStackTrace();
       } catch (RuntimeException e) {
            // no valid audio/video data has been received
            e.printStackTrace();
       }
   }
  
   public void play(View view) {
       try{
           myPlayer = new MediaPlayer();
           myPlayer.setDataSource(outputFile);
           myPlayer.prepare();
           myPlayer.start();
           
           playBtn.setEnabled(false);
           stopPlayBtn.setEnabled(true);
           text.setText("Recording Point: Playing");
           
           Toast.makeText(getApplicationContext(), "Start play the recording...", 
                   Toast.LENGTH_SHORT).show();
       } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
   }
   
   public void stopPlay(View view) {
       try {
           if (myPlayer != null) {
               myPlayer.stop();
               myPlayer.release();
               myPlayer = null;
               playBtn.setEnabled(true);
               stopPlayBtn.setEnabled(false);
               text.setText("Recording Point: Stop playing");
               
               Toast.makeText(getApplicationContext(), "Stop playing the recording...", 
                       Toast.LENGTH_SHORT).show();
           }
       } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
   }

}