Audio capture from the device is a bit more complicated than audio/video playback, but still fairly simple:
newTITLE, TIMESTAMP, and the all important
- MIME_TYPEnewMediaRecorder.AudioSource.MICThe example below illustrates how to set up, then start audio capture.
+The example class below illustrates how to set up, start and stop audio capture, and to play the recorded audio file.
- recorder = new MediaRecorder();
- ContentValues values = new ContentValues(3);
+/*
+ * The application needs to have the permission to write to external storage
+ * if the output file is written to the external storage, and also the
+ * permission to record audio. These permissions must be set in the
+ * application's AndroidManifest.xml file, with something like:
+ *
+ * <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+ * <uses-permission android:name="android.permission.RECORD_AUDIO" />
+ *
+ */
+package com.android.audiorecordtest;
- values.put(MediaStore.MediaColumns.TITLE, SOME_NAME_HERE);
- values.put(MediaStore.MediaColumns.TIMESTAMP, System.currentTimeMillis());
- values.put(MediaStore.MediaColumns.MIME_TYPE, recorder.getMimeContentType());
-
- ContentResolver contentResolver = new ContentResolver();
-
- Uri base = MediaStore.Audio.INTERNAL_CONTENT_URI;
- Uri newUri = contentResolver.insert(base, values);
-
- if (newUri == null) {
- // need to handle exception here - we were not able to create a new
- // content entry
+import android.app.Activity;
+import android.widget.LinearLayout;
+import android.os.Bundle;
+import android.os.Environment;
+import android.view.ViewGroup;
+import android.widget.Button;
+import android.view.View;
+import android.view.View.OnClickListener;
+import android.content.Context;
+import android.util.Log;
+import android.media.MediaRecorder;
+import android.media.MediaPlayer;
+
+import java.io.IOException;
+
+
+public class AudioRecordTest extends Activity
+{
+ private static final String LOG_TAG = "AudioRecordTest";
+ private static String mFileName = null;
+
+ private RecordButton mRecordButton = null;
+ private MediaRecorder mRecorder = null;
+
+ private PlayButton mPlayButton = null;
+ private MediaPlayer mPlayer = null;
+
+ private void onRecord(boolean start) {
+ if (start) {
+ startRecording();
+ } else {
+ stopRecording();
+ }
}
-
- String path = contentResolver.getDataFilePath(newUri);
- // could use setPreviewDisplay() to display a preview to suitable View here
-
- recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
- recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
- recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
- recorder.setOutputFile(path);
-
- recorder.prepare();
- recorder.start();
-
-Based on the example above, here's how you would stop audio capture.
-
- recorder.stop();
- recorder.release();
+ private void onPlay(boolean start) {
+ if (start) {
+ startPlaying();
+ } else {
+ stopPlaying();
+ }
+ }
+
+ private void startPlaying() {
+ mPlayer = new MediaPlayer();
+ try {
+ mPlayer.setDataSource(mFileName);
+ mPlayer.prepare();
+ mPlayer.start();
+ } catch (IOException e) {
+ Log.e(LOG_TAG, "prepare() failed");
+ }
+ }
+
+ private void stopPlaying() {
+ mPlayer.release();
+ mPlayer = null;
+ }
+
+ private void startRecording() {
+ mRecorder = new MediaRecorder();
+ mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
+ mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
+ mRecorder.setOutputFile(mFileName);
+ mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
+
+ try {
+ mRecorder.prepare();
+ } catch (IOException e) {
+ Log.e(LOG_TAG, "prepare() failed");
+ }
+
+ mRecorder.start();
+ }
+
+ private void stopRecording() {
+ mRecorder.stop();
+ mRecorder.release();
+ mRecorder = null;
+ }
+
+ class RecordButton extends Button {
+ boolean mStartRecording = true;
+
+ OnClickListener clicker = new OnClickListener() {
+ public void onClick(View v) {
+ onRecord(mStartRecording);
+ if (mStartRecording) {
+ setText("Stop recording");
+ } else {
+ setText("Start recording");
+ }
+ mStartRecording = !mStartRecording;
+ }
+ };
+
+ public RecordButton(Context ctx) {
+ super(ctx);
+ setText("Start recording");
+ setOnClickListener(clicker);
+ }
+ }
+
+ class PlayButton extends Button {
+ boolean mStartPlaying = true;
+
+ OnClickListener clicker = new OnClickListener() {
+ public void onClick(View v) {
+ onPlay(mStartPlaying);
+ if (mStartPlaying) {
+ setText("Stop playing");
+ } else {
+ setText("Start playing");
+ }
+ mStartPlaying = !mStartPlaying;
+ }
+ };
+
+ public PlayButton(Context ctx) {
+ super(ctx);
+ setText("Start playing");
+ setOnClickListener(clicker);
+ }
+ }
+
+ public AudioRecordTest() {
+ mFileName = Environment.getExternalStorageDirectory().getAbsolutePath();
+ mFileName += "/audiorecordtest.3gp";
+ }
+
+ @Override
+ public void onCreate(Bundle icicle) {
+ super.onCreate(icicle);
+
+ LinearLayout ll = new LinearLayout(this);
+ mRecordButton = new RecordButton(this);
+ ll.addView(mRecordButton,
+ new LinearLayout.LayoutParams(
+ ViewGroup.LayoutParams.WRAP_CONTENT,
+ ViewGroup.LayoutParams.WRAP_CONTENT,
+ 0));
+ mPlayButton = new PlayButton(this);
+ ll.addView(mPlayButton,
+ new LinearLayout.LayoutParams(
+ ViewGroup.LayoutParams.WRAP_CONTENT,
+ ViewGroup.LayoutParams.WRAP_CONTENT,
+ 0));
+ setContentView(ll);
+ }
+
+ @Override
+ public void onPause() {
+ super.onPause();
+ if (mRecorder != null) {
+ mRecorder.release();
+ mRecorder = null;
+ }
+
+ if (mPlayer != null) {
+ mPlayer.release();
+ mPlayer = null;
+ }
+ }
+}
+