private void UnregisterHostLifecycleEventHandlers()
 {
     HostLifecycleService.Suspending -= Suspending;
     HostLifecycleService.Resuming   -= Resuming;
     HostLifecycleService.Release();
 }
 private void RegisterHostLifecycleEventHandlers()
 {
     HostLifecycleService.Suspending += Suspending;
     HostLifecycleService.Resuming   += Resuming;
     HostLifecycleService.AddRef();
 }