private void addListener() { vl = new VideoListener(); gyro = new AttitudeGetter(); bar = new BarcodeListener(); // heg=new HeightGetter(); bg = new BatteryGetter(); pg = new PositionGetter(); drone.getNavDataManager().addAttitudeListener(gyro); // drone.getNavDataManager().addAltitudeListener(heg); drone.getNavDataManager().addBatteryListener(bg); drone.getVideoManager().addImageListener(vl); drone.getVideoManager().addImageListener(bar); }