This property is used to manage a group of AppearanceStyleInfos. Any AppearanceStyleInfo or AppearanceStyleInfo derivative type can be added to this collection. If there are multiple AppearanceStyleInfos' and the same property has different values, the last effective AppearanceStyleInfo property is used as the final property value. If a specific property value is "inherit" or "empty" in all AppearanceStyleInfos in the collection, the property's final value is "inherit" or "empty". If the Items property has no item, all property values are "inherit" or "empty".