Sissi,
Enumerations cannot be changed by user's at runtime. Write access is necessary for a user to be able to change an attribute value. So if your food enumeration has these options:
And you can create an entity with an attribute of type enumeration using this enumeration. Giving users write access to the attribute means they can select from the 3 enumeration options, but they cannot add another option to the enumeration or delete an option to the enumeration.
Hope that helps,
Mike
Hi Sissi,
A way around this might be a non persistable entity with your form where the anon user has access on. When the user submits the form you will create a persistable one in the submit microflow.
https://docs.mendix.com/refguide/persistability/#non-persistable