MARKUS

            var box = new TextBlock();

            box.MinWidth = 400;

            box.FontSize = 11;

            box.Text = "정말 삭제 하시겠습니까?";

            box.TextWrapping = System.Windows.TextWrapping.Wrap;

            DialogParameters parameters = new DialogParameters()

                Owner = Application.Current.MainWindow,

                Content = box,

                Header = "Confirm",

                Theme = new VisualStudio2013Theme(),

                ModalBackground = new SolidColorBrush { Color = Colors.Black, Opacity = 0.6 },

                OkButtonContent = "Yes",

                CancelButtonContent = "No",

                Closed = delegate (object windowSender, WindowClosedEventArgs wc)

                {

                    if(wc.DialogResult == true)

                    {

                        //선택된 어도너가 있을시 삭제가 되지 않음

                        SelectionSet.Instance.UnSelect(this);

                        Button content = (sender as Button);

                        MarkupInfoItem item = content.CommandParameter as MarkupInfoItem;

                        DeleteItem(item);

                    }

                }

            };

            RadWindow.Confirm(parameters);