private void btnCancel_Click(object sender, RoutedEventArgs e)
        {
            Window hostWindow = GetParent<Window>(sender as Button);
            if (hostWindow != null)
            {
                hostWindow.Close();
            }
        }

        public static T GetParent<T>(UIElement  uiElement) where T : class
        {
            T result;
            var dp = LogicalTreeHelper.GetParent(uiElement);
            result = dp as T;
            while (result == null)
            {
                dp = LogicalTreeHelper.GetParent(dp);
                result = dp as T;
                if (dp == null) return null;
            }
            return result;
        }