AudioRecordWithCallbacksActivity.java

package com.google.mcommerce.sample.android.chapter10.mediarecorder;

import android.app.Activity;
import android.media.AudioFormat;
import android.media.AudioRecord;
import android.media.AudioRecord.OnRecordPositionUpdateListener;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.util.Log;

public class AudioRecordWithCallbacksActivity extends Activity {
	private static final String TAG = "AudioRecordCallbacks";
	private int mAudioBufferSize;
	private int mAudioBufferSampleSize;
	private AudioRecord mAudioRecord;
	private boolean inRecordMode = false;

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		initAudioRecord();
	}

	@Override
	public void onResume() {
		super.onResume();
		Log.v(TAG, "Resuming...");
		inRecordMode = true;
		Thread t = new Thread(new Runnable() {

			@Override
			public void run() {
				getSamples();
			}
		});
		t.start();
	}

	protected void onPause() {
		Log.v(TAG, "Pausing...");
		inRecordMode = false;
		super.onPause();
	}

	@Override
	protected void onDestroy() {
		Log.v(TAG, "Destroying...");
		if (mAudioRecord != null) {
			mAudioRecord.release();
			Log.v(TAG, "Released AudioRecord");
		}
		super.onDestroy();
	}

	public OnRecordPositionUpdateListener mListener = new OnRecordPositionUpdateListener() {

		public void onPeriodicNotification(AudioRecord recorder) {
			Log.v(TAG, "in onPeriodicNotification");
		}

		public void onMarkerReached(AudioRecord recorder) {
			Log.v(TAG, "in onMarkerReached");
			inRecordMode = false;
		}
	};

	private void initAudioRecord() {
		try {
			int sampleRate = 8000;
			int channelConfig = AudioFormat.CHANNEL_IN_MONO;
			int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
			mAudioBufferSize = 2 * AudioRecord.getMinBufferSize(sampleRate,
					channelConfig, audioFormat);
			mAudioBufferSampleSize = mAudioBufferSize / 2;
			mAudioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC,
					sampleRate, channelConfig, audioFormat, mAudioBufferSize);
			Log.v(TAG, "Setup of AudioRecord okay. Buffer size = "
					+ mAudioBufferSize);
			Log.v(TAG, "   Sample buffer size = " + mAudioBufferSampleSize);
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		}

		mAudioRecord.setNotificationMarkerPosition(10000);
		mAudioRecord.setPositionNotificationPeriod(1000);
		mAudioRecord.setRecordPositionUpdateListener(mListener);

		int audioRecordState = mAudioRecord.getState();
		if (audioRecordState != AudioRecord.STATE_INITIALIZED) {
			Log.e(TAG, "AudioRecord is not properly initialized");
			finish();
		} else {
			Log.v(TAG, "AudioRecord is initialized");
		}
	}

	private void getSamples() {
		if (mAudioRecord == null)
			return;

		short[] audioBuffer = new short[mAudioBufferSampleSize];

		mAudioRecord.startRecording();

		int audioRecordingState = mAudioRecord.getRecordingState();
		if (audioRecordingState != AudioRecord.RECORDSTATE_RECORDING) {
			Log.e(TAG, "AudioRecord is not recording");
			finish();
		} else {
			Log.v(TAG, "AudioRecord has started recording...");
		}

		while (inRecordMode) {
			int samplesRead = mAudioRecord.read(audioBuffer, 0,
					mAudioBufferSampleSize);
			Log.v(TAG, "Got samples: " + samplesRead);
			Log.v(TAG, "First few sample values: " + audioBuffer[0] + ", "
					+ audioBuffer[1] + ", " + audioBuffer[2] + ", "
					+ audioBuffer[3] + ", " + audioBuffer[4] + ", "
					+ audioBuffer[5] + ", " + audioBuffer[6] + ", "
					+ audioBuffer[7] + ", " + audioBuffer[8] + ", "
					+ audioBuffer[9] + ", ");
		}

		mAudioRecord.stop();
		Log.v(TAG, "AudioRecord has stopped recording");
	}
}