Microsoft.Windows.Controls.Ribbon.RibbonMenuButton.OnPreviewMouseDown C# (CSharp) Метод

        protected override void OnPreviewMouseDown(MouseButtonEventArgs e)
        {
            base.OnPreviewMouseDown(e);
            if (IsDropDownOpen)
            {
                // Close the drop down if the click happened on the toggle button.
                if (RibbonHelper.IsMousePhysicallyOver(this))
                {
                    IsDropDownOpen = false;
                    e.Handled = true;
                }
            }
        }