Cách sử dụng Android MediaRecorder

<RelativeLayout xmlns:androclass="http://schemas.android.com/apk/res/android"  
    xmlns:tools="http://schemas.android.com/tools"  
    android:layout_width="match_parent"  
    android:layout_height="match_parent"  
    android:paddingBottom="@dimen/activity_vertical_margin"  
    android:paddingLeft="@dimen/activity_horizontal_margin"  
    android:paddingRight="@dimen/activity_horizontal_margin"  
    android:paddingTop="@dimen/activity_vertical_margin"  
    tools:context=".MainActivity" >  
  
    <Button  
        android:id="@+id/button1"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_alignParentLeft="true"  
        android:layout_alignParentTop="true"  
        android:layout_marginLeft="68dp"  
        android:layout_marginTop="50dp"  
        android:text="Start Recording"  
        android:onClick="startRecording"  
         />  
  
    <Button  
        android:id="@+id/button2"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_alignLeft="@+id/button1"  
        android:layout_below="@+id/button1"  
        android:layout_marginTop="64dp"  
        android:text="Stop Recording"   
        android:onClick="stopRecording"  
        />  
  
</RelativeLayout>  

package com.javatpoint.mediarecorder;  
import java.io.File;  
import java.io.IOException;  
import android.app.Activity;  
import android.content.ContentResolver;  
import android.content.ContentValues;  
import android.content.Intent;  
import android.media.MediaRecorder;  
import android.net.Uri;  
import android.os.Bundle;  
import android.os.Environment;  
import android.provider.MediaStore;  
import android.util.Log;  
import android.view.View;  
import android.widget.Button;  
import android.widget.Toast;  
  
public class MainActivity extends Activity {  
      MediaRecorder recorder;  
      File audiofile = null;  
      static final String TAG = "MediaRecording";  
      Button startButton,stopButton;  
  
      @Override  
      public void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main);  
        startButton = (Button) findViewById(R.id.button1);  
        stopButton = (Button) findViewById(R.id.button2);  
      }  
  
      public void startRecording(View view) throws IOException {  
        startButton.setEnabled(false);  
        stopButton.setEnabled(true);  
        
        File dir = Environment.getExternalStorageDirectory();  
        try {  
          audiofile = File.createTempFile("sound", ".3gp", dir);  
        } catch (IOException e) {  
          Log.e(TAG, "external storage access error");  
          return;  
        }  

        recorder = new MediaRecorder();  
        recorder.setAudioSource(MediaRecorder.AudioSource.MIC);  
        recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);  
        recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);  
        recorder.setOutputFile(audiofile.getAbsolutePath());  
        recorder.prepare();  
        recorder.start();  
      }  
  
      public void stopRecording(View view) {  
        startButton.setEnabled(true);  
        stopButton.setEnabled(false);  
   
        recorder.stop();  
        recorder.release();  
      
        addRecordingToMediaLibrary();  
      }  
  
      protected void addRecordingToMediaLibrary() {  
          
        ContentValues values = new ContentValues(4);  
        long current = System.currentTimeMillis();  
        values.put(MediaStore.Audio.Media.TITLE, "audio" + audiofile.getName());  
        values.put(MediaStore.Audio.Media.DATE_ADDED, (int) (current / 1000));  
        values.put(MediaStore.Audio.Media.MIME_TYPE, "audio/3gpp");  
        values.put(MediaStore.Audio.Media.DATA, audiofile.getAbsolutePath());  
           
        ContentResolver contentResolver = getContentResolver();  
        Uri base = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;  
        Uri newUri = contentResolver.insert(base, values);  
  
         
        sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, newUri));  
        Toast.makeText(this, "Added File " + newUri, Toast.LENGTH_LONG).show();  
      }  
    }