synchronized void start() {
if (!serviceMgr.isTowerConnected())
throw new IllegalStateException("Service manager must be connected.");
IDroneApi droneApi = droneApiRef.get();
if (isStarted(droneApi)) return;
try {
droneApi =
serviceMgr
.get3drServices()
.registerDroneApi(this.apiListener, serviceMgr.getApplicationId());
droneApi.asBinder().linkToDeath(binderDeathRecipient, 0);
} catch (RemoteException e) {
throw new IllegalStateException("Unable to retrieve a valid drone handle.");
}
if (asyncScheduler == null || asyncScheduler.isShutdown())
asyncScheduler = Executors.newFixedThreadPool(1);
addAttributesObserver(droneApi, this.droneObserver);
resetFlightTimer();
droneApiRef.set(droneApi);
}
synchronized void destroy() {
IDroneApi droneApi = droneApiRef.get();
removeAttributesObserver(droneApi, this.droneObserver);
try {
if (isStarted(droneApi)) {
droneApi.asBinder().unlinkToDeath(binderDeathRecipient, 0);
serviceMgr.get3drServices().releaseDroneApi(droneApi);
}
} catch (RemoteException | NoSuchElementException e) {
Log.e(TAG, e.getMessage(), e);
}
if (asyncScheduler != null) {
asyncScheduler.shutdownNow();
asyncScheduler = null;
}
droneApiRef.set(null);
}
