(Xamarin.Forms) System.ArgumentException: Failed to bind to the GetOnServiceConnectedHandler method.

Question

I am trying to implement an AccessibilityService as shown below (Xamarin Forms + VisualStudio 2015):

[Service(Label = "myApp", Permission = Manifest.Permission.BindAccessibilityService)]
[IntentFilter(new[] { "android.accessibilityservice.AccessibilityService" })]
public class MyAccessibilityService: AccessibilityService
{
     ...
     ...
      protected override void OnServiceConnected()
     {
         ...
         ...
     }
}

But I get a runtime error System.ArgumentException: Couldn't bind to method 'GetOnServiceConnectedHandler'.

And the breakpoint set inside the method OnServiceConnecteddoes not fall.

Note. All permissions are set in the properties of the .Droid project, so there should not be access rights.

Any pointer would be very helpful.