When a list subtype is created, it is created as a simple text one, and the "list" behavior is added only as a widget.
The problem is that using that field in a view looses the characteristic of a list, it is just a text field, so for example the user cannot filter by allowed values.
This does not happen with a standard Text/List field.
Is it possible to define a field as a list so that this characteristic is preserved when used in a view?
Closed: works as designed
1.0
Code
Please read again module description
Please note: all custom fields are not entity fields, so you cannot benefit from field widget, field renderer, or the entity formatter. It's just for the data.