MVVMCross IMvxGeoLocationWatcher Success Action never fires on Android - xamarin.android

Question

I created a very simple test app to try and reverse geocode my current lat/long into an address.
Here is the code for my ViewModel:
namespace LoginProductsMVVM.Core.ViewModels
{
public class ProductDetailViewModel
: MvxViewModel
{
public void Init(Product product)
{
Product = product;
}
private Product _product;
public Product Product
{
get { return _product; }
set { _product = value;
RaisePropertyChanged (() => Product); }
}
private string _latitude;
public string Latitude{
get { return _latitude; }
set { _latitude = value; RaisePropertyChanged(() => Latitude); }
}
private string _longitude;
public string Longitude{
get { return _longitude; }
set { _longitude = value; RaisePropertyChanged(() => Longitude); }
}
private string _address;
public string Address{
get { return _address; }
set { _address = value; RaisePropertyChanged(() => Address); }
}
private IMvxGeoLocationWatcher _watcher;
public IMvxGeoLocationWatcher Watcher
{
get
{
_watcher = Mvx.Resolve<IMvxGeoLocationWatcher> ();
return _watcher;
}
}
public ProductDetailViewModel(IMvxGeoLocationWatcher watcher)
{
_watcher = watcher;
_watcher.Start (new MvxGeoLocationOptions (), OnLocation, OnError);
}
void OnLocation (MvxGeoLocation location)
{
Latitude = location.Coordinates.Latitude.ToString();
Longitude = location.Coordinates.Longitude.ToString();
// Android Location specific stuff
var activity = Mvx.Resolve<IMvxAndroidCurrentTopActivity> ().Activity;
Geocoder geocdr = new Geocoder (activity.BaseContext);
IList<Address> addresses = geocdr.GetFromLocation (double.Parse(Latitude), double.Parse(Longitude), 1);
addresses.ToList().ForEach ((addr) => Address += addr.ToString() + "\r\n\r\n");
}
void OnError (MvxLocationError error)
{
Mvx.Error ("Seen location error {0}", error);
}
}
}
I have a break point in my OnLocation method but it never gets in there. Am I missing something for this to work properly on Android? It appears to work just fine for iOS...

Answer 1

Per Odahan here:
Well... I investigated a bit more : The problem is known and can be seen on many devices. This is not a MvvmCross problem. Short answer : the device needs to be rebooted and all is working like a charm... It seems Google sent some updates that are causing the problem.
Here is a thread speaking about this problem and a similar one concerning the GeoCode class :
https://code.google.com/p/android/issues/detail?id=38009
So : can be closed, MvvmCross is ok but others can face this bug so my explanations and the link here.

Answer 2

When you say it never fires 'success', does the success actually ever occur?
There could be lots of things going wrong in the GPS code - eg your app might not have privilege, your phone might have A-GPS or GPS disabled, or you might even be running on a location-less emulator - all of this is possible from your description.
It'a also worth noting that Xamarin.Android has long standing issues with hitting breakpoints - so it's better to add trace than to rely on breakpoint hitting :/
Perhaps try running though N=8 from http://mvvmcross.wordpress.com/ - does that help at all? (N=9 is also worth watching as it shows one way to allow multiple viewmodels to use the geowatcher)