How to route a mono sound from an android device to a handset/handfree

Today i was doing an RnD to route a mono sound from an android device to a handsfree/handset and after googling many things and trying out a few i was able to come up with a simple solution using BluetoothHandsfree profile.


Here is a code snippet:
<manifest>

<uses-permission android:name="
android.permission.MODIFY_AUDIO_SETTINGS" />

</manifest>

.................

BluetoothAdapter mBluetoothAdapter;

mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

if (mBluetoothAdapter == null) {

toast("Device does not support Bluetooth");

} else {

toast("Bluetooth is supported");

if (!mBluetoothAdapter.isEnabled()) {

toast("Requesting for Bluetooth");

Intent discoverableIntent = new Intent(

BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);

discoverableIntent.putExtra(

BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);

startActivityForResult(discoverableIntent, REQUEST_ENABLE_BT);

} else {

toast("Bluetooth Enabled");

}

}

mBluetoothAdapter.getProfileProxy(getApplicationContext(),

mProfileListener, BluetoothProfile.HEADSET);

private BluetoothProfile.ServiceListener mProfileListener = new BluetoothProfile.ServiceListener() {

public void onServiceConnected(int profile, BluetoothProfile proxy) {

if (profile == BluetoothProfile.HEADSET) {

mBluetoothHeadset = (BluetoothHeadset) proxy;

Log.i(tag, "***** Headset proxy obtained *****");

AudioManager audioManager = (AudioManager) getSystemService(AUDIO_SERVICE);

audioManager.setMode(AudioManager.MODE_IN_CALL);

audioManager.startBluetoothSco();

audioManager.setBluetoothScoOn(true);

short[] soundData = new short[8000 * 20];

for (int iii = 0; iii < 20 * 8000; iii++) {

soundData[iii] = 32767; // High Note

iii++;

soundData[iii] = 32767; // High Note

iii++;

soundData[iii] = -32768; // Low Note

iii++;

soundData[iii] = -32768; // Low Note

}

AudioTrack audioTrack = new AudioTrack(

AudioManager.STREAM_VOICE_CALL, 8000,

AudioFormat.CHANNEL_OUT_MONO,

AudioFormat.ENCODING_PCM_16BIT, soundData.length

* Short.SIZE, AudioTrack.MODE_STATIC);

audioTrack.write(soundData, 0, soundData.length);

audioTrack.play();

}

}

public void onServiceDisconnected(int profile) {

if (profile == BluetoothProfile.HEADSET) {

mBluetoothHeadset = null;

Log.i(tag, "***** Headset Disconnected *****");

}

}

};

After running this code in an activity a buzz sound can be listened in a headset/handsfree.