How to use

addOnActiveSessionsChangedListener

method

in

android.media.session.MediaSessionManager

public synchronized void setRemoteControlListener(Listener listener) throws RemoteException {
  if (Log.isLoggable("NowPlayCardListener", 3)) {
    Log.d("NowPlayCardListener", "setRemoteControlListener: " + listener);
  }
  MediaSessionManager manager = (MediaSessionManager) this.mContext.getApplicationContext().getSystemService("media_session");
  if (listener != null) {
    manager.addOnActiveSessionsChangedListener(this, null);
    this.mNowPlayCardListener = listener;
    checkForMediaSession();
  } else {
    manager.removeOnActiveSessionsChangedListener(this);
    this.mNowPlayCardListener = null;
    updateMediaSessionCallback(null);
  }
}

@Override
public boolean onCreate() {
  if (!hasPermission())
    return false;
  players = new HashMap<>();
  try {
    MediaSessionManager manager = (MediaSessionManager) context.getSystemService(Context.MEDIA_SESSION_SERVICE);
    if (null == manager)
      return false;
    manager.addOnActiveSessionsChangedListener(MprisReceiverPlugin.this, new ComponentName(context, NotificationReceiver.class), new Handler(Looper.getMainLooper()));
    createPlayers(manager.getActiveSessions(new ComponentName(context, NotificationReceiver.class)));
    sendPlayerList();
  } catch (Exception e) {
    Log.e(TAG, "Exception", e);
  }
  return true;
}

manager.addOnActiveSessionsChangedListener(mSessionsChangedListener, componentName);
synchronized (this) {
  mActiveSessions = manager.getActiveSessions(componentName);