Setting more PopupListView button properties on list selection change (not just text) #113

Looks like currently there's no easy way to control what PopupListView's button properties are changed when selection changes. For example, I'd like to change button icon to the currently selected item's image.

I found one way to achieve this via subclassing PopupListView and overriding refreshSelection, but it's not pretty, maybe a dynamic function similar to itemToText could be added to plug in the functionality without subclassing?