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

        protected override void ClearContainerForItemOverride(DependencyObject element, object item)
        {
            base.ClearContainerForItemOverride(element, item);

            // RibbonComboBox containers are pre-generated.
            // When dropdown is opened for the first time ever and ItemContainerGenerator
            // is hooked up to ItemsPanel, existing containers are cleared, causing _galleryCount to be -ve.
            // Hence the check for _galleryCount > 0
            if (element is RibbonGallery && _galleryCount > 0)
            {
                HasGallery = (--_galleryCount > 0);
            }
        }