protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
Xamarin.Essentials.Platform.Init(this, savedInstanceState);
SetContentView(Resource.Layout.activity_main);
FManager = FragmentManager;
BottomNavigationView navigation = FindViewById <BottomNavigationView>(Resource.Id.navigation);
navigation.SetOnNavigationItemSelectedListener(this);
OnNavigationItemSelected(navigation.Menu.GetItem(0));
sMessageEngine = Nearby.GetMessageEngine(this);
RequestPermissions();
sMessageEngine.RegisterStatusCallback(new MyStatusCallback()).AddOnCompleteListener(new TaskListener(this, " RegisterStatusCallback")).AddOnFailureListener(new TaskListener(this, " RegisterStatusCallback"));
}