Geolocator.RequestAccessAsync throws "method called at unexpected time" exception - exception

Question

I have a chunk of code I use to get device location. This is done in a monogame windows uwp project. The following code worked before (I was on VS2015 Community). I recent did a fresh OS and install VS2017 Community. I finally got my project to build and run. The only thing not working is the Geolocator.RequestAccessAsync is throwing a "method called at unexpected time" exception. Any ideas?
public async Task<Vector2> GetDeviceGps()
{
var accessStatus = await Geolocator.RequestAccessAsync();
switch (accessStatus)
{
case GeolocationAccessStatus.Allowed:
// If DesiredAccuracy or DesiredAccuracyInMeters are not set (or value is 0), DesiredAccuracy.Default is used.
Geolocator geolocator = new Geolocator { DesiredAccuracyInMeters = 10 };
// Subscribe to the StatusChanged event to get updates of location status changes.
//geolocator.StatusChanged += OnStatusChanged;
// Carry out the operation.
Geoposition pos = await geolocator.GetGeopositionAsync();
return new Vector2((float)pos.Coordinate.Point.Position.Longitude, (float)pos.Coordinate.Point.Position.Latitude);
case GeolocationAccessStatus.Denied:
//Do something!
break;
case GeolocationAccessStatus.Unspecified:
//Murp
break;
}
return Vector2.Zero;
}
This is invoked and handled like so (called from update method of game):
mapper.GetDeviceGps().ContinueWith(pos =>
{
Vector2 bob = pos.Result;
});

Answer 1

When you run the RequestAccessAsync for the first time in your app, the user will be asked to grant your app the location permission. Therefore the method needs to be executed in the UI thread.