Specifies an enabled state for the target UI element.
NuGet Package: DevExpress.ExpressApp.ConditionalAppearance
true, to enable the target UI element; false, to disable it.
If there are conditional appearance rules that change the enabled state within the rules appropriate for the target UI element, the AppearanceObject‘s Enabled property returns the enabled state specified by the rule with the higher priority (see IAppearance.Priority). If there are no rules that change the enabled state, the Enabled property returns null (Nothing in VB).