As I understand it is common issue of Philips Android TV users (for example p. 22 in this thread, or that discussion).
In general, template for your task is Service which tracking plug/unplug event and volume of "system/music" audio stream (or media button press) than make corresponding changes on "wired headphones" audio "stream" (there is no such stream in "standard" Android, but obviously
something like that present in "Android Philips") level. The issue is that seems to be impossible change volume "wiredheadphones" audio stream level using only Android SDK without "Philips Android TV API" (probably it's not a public).
Template source code for "VolumeTrackingService" may be something like this:
public class VolumeTrackingService extends Service {
private static final String TAG = VolumeTrackingService.class.getSimpleName();
public static final String ACTION_START = "VolumeTrackingService.ACTION_START";
public static final String ACTION_STOP = "VolumeTrackingService.ACTION_STOP";
HeadsetPlugIntentReceiver mHeadsetPlugReceiver;
private static boolean mHeadsetPlugged = false;
private SettingsContentObserver mSettingsContentObserver;
@Nullable
@Override
public IBinder onBind(Intent intent) {
return null;
}
@Override
public void onCreate() {
super.onCreate();
mHeadsetPlugReceiver = new HeadsetPlugIntentReceiver();
registerReceiver(mHeadsetPlugReceiver, new IntentFilter(Intent.ACTION_HEADSET_PLUG));
mSettingsContentObserver = new SettingsContentObserver(new Handler());
getApplicationContext().getContentResolver().registerContentObserver(android.provider.Settings.System.CONTENT_URI, true, mSettingsContentObserver);
}
@Override
public void onDestroy() {
getApplicationContext().getContentResolver().unregisterContentObserver(mSettingsContentObserver);
unregisterReceiver(mHeadsetPlugReceiver);
super.onDestroy();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
if (intent != null) {
String actionRequested = intent.getAction();
if (ACTION_START.equals(actionRequested)) {
} else if (ACTION_STOP.equals(actionRequested)) {
stopSelf();
}
}
return START_STICKY;
}
private int getSystemVolumeInPercentage() {
AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
final int streamVolumeMax = audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
final int streamVolume = audioManager.getStreamVolume(AudioManager.STREAM_MUSIC);
return 100 * streamVolume / streamVolumeMax;
}
private void setHeadphonesVolume(int volumeInPercentage) {
// there should be magic of wired headphones volume level changing
}
private void processVolumeChanges() {
if (mHeadsetPlugged) {
int systemVolumeInPercentage = getSystemVolumeInPercentage();
setHeadphonesVolume(systemVolumeInPercentage);
}
}
public class SettingsContentObserver extends ContentObserver {
public SettingsContentObserver(Handler handler) {
super(handler);
}
@Override
public boolean deliverSelfNotifications() {
return super.deliverSelfNotifications();
}
@Override
public void onChange(boolean selfChange) {
super.onChange(selfChange);
if (mHeadsetPlugged ) {
processVolumeChanges();
}
}
}
public class HeadsetPlugIntentReceiver extends android.content.BroadcastReceiver {
@Override
public void onReceive(Context ctx, Intent intent) {
if (intent.getAction().equals(android.media.AudioManager.ACTION_HEADSET_PLUG)) {
mHeadsetPlugged = intent.getIntExtra("state", 0) == 1;
}
}
}
}
unfortunately it not solves main issue: changing volume level of wired headphones (probably it's impossible without "Philips Android TV API").
But if your surround sound system has remote control You can do some workaround: emulate sound system remote control commands in Service described above and send it via IR dongle connected to USB Host of your Philips 49PUS6401 Android TV.
