public override void Visit(ChoiceQuestion element)
 {
     _result = new FormPanel();
     _result.Children.Add(new Label { Content = element.Title });
     foreach (var choice in element.Choices)
     {
         _result.Children.Add(new CheckBox { Content = choice });
     }
     AddChildren(element);
 }
 public abstract void Visit(ChoiceQuestion element);