ReadOnlyOptionalActionEventHandlerPropertyWrapper
class ReadOnlyOptionalActionEventHandlerPropertyWrapper(wraps: OptionalActionEventHandlerProperty) : ReadOnlyPropertyWrapper<ActionEventHandler?, Property<ActionEventHandler?>> , ReadOnlyOptionalActionEventHandlerProperty
Boilerplate which avoids having to use generics.
Similar to ReadOnlyActionEventHandlerPropertyWrapper, but the value can also be null.