Boogaart.Silverlight.Behaviors.Popup.PopupWatcher.OnPopupOpened C# (CSharp) Method

            private void OnPopupOpened(object sender, EventArgs e)
            {
                var popupAncestor = FindHighestAncestor(this.popup);

                if (popupAncestor == null)
                {
                    return;
                }

                popupAncestor.AddHandler(Windows.Popup.MouseLeftButtonDownEvent, (MouseButtonEventHandler)OnMouseLeftButtonDown, true);
            }