private void UnsubscribeControl(DashboardableControlHostPanel control)
        {
            control.MouseMove  -= control_MouseMove;
            control.MouseLeave -= control_MouseLeave;
            control.MouseDown  -= control_MouseDown;
            control.MouseUp    -= control_MouseUp;

            control.NotifyEditModeChange(false);
        }
        private void SubscribeControl(DashboardableControlHostPanel control)
        {
            control.MouseMove  += control_MouseMove;
            control.MouseLeave += control_MouseLeave;
            control.MouseDown  += control_MouseDown;
            control.MouseUp    += control_MouseUp;

            control.NotifyEditModeChange(true);
        }