The dropdowns should provide an easy way to have certain items in the list as inactive. The easiest way could be an attribute. In addition to [textField] and [valueField] an [inactiveField] could be added.

If the assigned data field is a boolean the item in the list can be either enabled or disabled.

Reason for this request is, that those value lists often are dynamic, meaning that an item in the list could be superseded by a new one. But the existing records in the database still could reference the older item, but new records should be prevented from selecting the new item.