private bool RaiseContextMenuOpeningEvent(IInputElement source, double x, double y, bool userInitiated)
        {
            // Fire the event
            ContextMenuEventArgs args     = new ContextMenuEventArgs(source, true /* opening */, x, y);
            DependencyObject     sourceDO = source as DependencyObject;

            if (userInitiated && sourceDO != null)
            {
                if (InputElement.IsUIElement(sourceDO))
                {
                    ((UIElement)sourceDO).RaiseEvent(args, userInitiated);
                }
                else if (InputElement.IsContentElement(sourceDO))
                {
                    ((ContentElement)sourceDO).RaiseEvent(args, userInitiated);
                }
                else if (InputElement.IsUIElement3D(sourceDO))
                {
                    ((UIElement3D)sourceDO).RaiseEvent(args, userInitiated);
                }
                else
                {
                    source.RaiseEvent(args);
                }
            }
            else
            {
                source.RaiseEvent(args);
            }


            if (!args.Handled)
            {
                // No one handled the event, auto show any available ContextMenus

                // Saved from the bubble up the tree where we looked for a set ContextMenu property
                DependencyObject o = args.TargetElement;
                if ((o != null) && ContextMenuService.ContextMenuIsEnabled(o))
                {
                    // Retrieve the value
                    object      menu = ContextMenuService.GetContextMenu(o);
                    ContextMenu cm   = menu as ContextMenu;
                    cm.SetValue(OwnerProperty, o);
                    cm.Closed += new RoutedEventHandler(OnContextMenuClosed);

                    if ((x == -1.0) && (y == -1.0))
                    {
                        // We infer this to mean that the ContextMenu was opened with the keyboard
                        cm.Placement = PlacementMode.Center;
                    }
                    else
                    {
                        // If there is a CursorLeft and CursorTop, it was opened with the mouse.
                        cm.Placement = PlacementMode.MousePoint;
                    }

                    // Clear any open tooltips
                    RaiseToolTipClosingEvent(true /*reset */);

                    cm.SetCurrentValueInternal(ContextMenu.IsOpenProperty, BooleanBoxes.TrueBox);

                    return(true); // A menu was opened
                }

                return(false); // There was no menu to open
            }

            // Clear any open tooltips since someone else opened one
            RaiseToolTipClosingEvent(true /*reset */);

            return(true); // The event was handled by someone else
        }