nature_net.user_controls.collection_listbox.contributions_PreviewTouchUp C# (CSharp) Метод

        void contributions_PreviewTouchUp(object sender, System.Windows.Input.TouchEventArgs e)
        {
            //TextBlock tm = new TextBlock(); tm.Foreground = Brushes.White;
            //Canvas.SetLeft(tm, 200); Canvas.SetTop(tm, debug_var);
            //tm.Text = "TOUCH UP"; tm.FontSize = 16; tm.FontWeight = FontWeights.Bold;
            ////window_manager.main_canvas.Children.Add(tm);
            //debug_canvas.Children.Add(tm);
            //debug_var = debug_var + 30;
            //if (debug_var > 600) { debug_var = 10; debug_canvas.Children.RemoveRange(0, debug_canvas.Children.Count); }
            if (touch_points.Count > 0)
            {
                ScrollViewer scroll = configurations.GetDescendantByType(this.contributions, typeof(ScrollViewer)) as ScrollViewer;
                //double dv = e.GetTouchPoint(this.contributions).Position.X - touch_points[touch_points.Count - 1].Position.X;
                double dv = e.GetTouchPoint(this.contributions).Position.X - touch_points[0].Position.X;
                try
                {
                    //scroll.ScrollToHorizontalOffset(scroll.HorizontalOffset + (-2 * dv));
                    scroll.ScrollToHorizontalOffset(last_scroll_offset + (-1 * dv));
                }
                catch (Exception) { }
                last_scroll_offset = scroll.HorizontalOffset;
            }

            this.touch_points.Clear();
            consecutive_drag_points = 0;
            UIElement element = sender as UIElement;
            element.ReleaseTouchCapture(e.TouchDevice);
            //e.Handled = false;
        }