internal void ShowContextMenu(HashSet <ClockVM> cc, System.Drawing.Point screenPosition,
                                      System.Windows.Forms.ToolStripDropDownDirection dir = System.Windows.Forms.ToolStripDropDownDirection.BelowRight)
        {
            if (cc.Count == 0) // only takes place in multiselect mode (header)
            {
                ClockContextMenuStrip.MyEmptyContextMenu.Placement = System.Windows.Controls.Primitives.PlacementMode.MousePoint;
                ClockContextMenuStrip.MyEmptyContextMenu.IsOpen    = true;
                return;
            }

            MyClockContextMenuStrip.MyClocks = cc;
            MyClockContextMenuStrip.UpdateContents();
            MyClockContextMenuStrip.Placement = System.Windows.Controls.Primitives.PlacementMode.MousePoint;
            MyClockContextMenuStrip.IsOpen    = true;
        }
        internal void ShowContextMenu(System.Drawing.Point screenPosition,
                                      System.Windows.Forms.ToolStripDropDownDirection dir = System.Windows.Forms.ToolStripDropDownDirection.BelowRight)
        {
            var cc = new HashSet <ClockVM>();

            foreach (ClockVM cd in Clocks.VMs)
            {
                if (cd.Checked)
                {
                    cc.Add(cd);
                }
            }
            if (cc.Count == 0) // only takes place in multiselect mode (header)
            {
                var cms = new ContextMenu();
                cms.Items.Add(MyFillColumnsItem);
                //cms.Show(screenPosition, dir);
                cms.Placement = System.Windows.Controls.Primitives.PlacementMode.MousePoint;
                cms.IsOpen    = true;
                return;
            }

            if (ImportMode)
            {
                return;
            }

            MyClockContextMenuStrip.MyClocks = cc;
            MyClockContextMenuStrip.UpdateContents();
            MyClockContextMenuStrip.Items.Remove(MyToolStripSeparator);
            MyClockContextMenuStrip.Items.Remove(MyFillColumnsItem);
            MyClockContextMenuStrip.Items.Add(MyToolStripSeparator);
            MyClockContextMenuStrip.Items.Add(MyFillColumnsItem);
            MyClockContextMenuStrip.Placement = System.Windows.Controls.Primitives.PlacementMode.MousePoint;
            //MyClockContextMenuStrip.Show(screenPosition, dir);
            MyClockContextMenuStrip.IsOpen = true;
        }