public static ReactiveCommand <T1, T2> SetupErrorHandling <T1, T2>(this ReactiveCommand <T1, T2> command, CompositeDisposable disposable)
 {
     command.ThrownExceptions
     .Subscribe(async ex => await Application.Current.MainPage.DisplayAlert("Error running command", ex.Message, "OK"))
     .DisposeWith(disposable);
     command.DisposeWith(disposable);
     return(command);
 }