[Flow] form with items that do not represent members of an object

[Axel Wüstemann]

Hello,

as I could understand up to now, forms rely on model objects, so all 
formfields need to represent an object member.

Now I have the case, that I want to select an item from a selectbox, but 
alternatively set a new item of that type.

Example:
In my selectbox "bar" I can choose between foo1, foo2 or foo3, but now I 
want to introduce a foo4 value - so additional to the selectbox "bar" I 
want to have a text filed "newBar" where I can enter the value foo4.

Maybe I can introduce a "newBar" menmber in my domain object, but than I 
would need to exclude it from being persisted.

How I can achieve that?

Thanks

Axel