RadListPicker - some problems

  public class ResultsItemsViewModel
    {
        public ObservableCollection<ResultsItem> ResultsItems { get; set; }
        public ResultsItemsViewModel()
        {
            this.ResultsItems = new ObservableCollection<ResultsItem>()
            
            {
              new ResultsItem { Value = "OK" },
              new ResultsItem { Value = "Failed" },
             };
        }
    }

 <HorizontalStackLayout Grid.Row="1" Grid.Column="0" HorizontalOptions="CenterAndExpand" VerticalOptions="CenterAndExpand" Margin="10">
                <Label Text="Results:"/>
                <telerikInput:RadListPicker Placeholder="Select Result" HeightRequest="30"
                          ItemsSource="{Binding ResultsItems}"
                          DisplayMemberPath="Value"
                         SelectionChanged="OnResultsSelectionChanged">
                    <telerikInput:RadListPicker.BindingContext>
                        <local:ResultsItemsViewModel/>
                    </telerikInput:RadListPicker.BindingContext>
                </telerikInput:RadListPicker>
            </HorizontalStackLayout>