Associating an array to multiple text fields in a form

I have a model that has the following classes: ShoppingList, Item and

Product is just a list of product names: Apple, Orange, Banana,
Grape. The table has two columns: ID and NAME.

– A ShoppingList has a name (string) and many Item objects.

– Each Item has a quantity (integer) and to-one relationship to a

My ShoppingList’s edit view has a form that contains a textfield for the
name of
a shopping list and a table of items and their quantities:

Name: MyShoppingList

Qty. Item
3 Apples
0 Oranges
1 Pear

The model object for this view is, of course, a ShoppingList.

I am trying to bind each text field to the quantity attribute of each
item in the shopping list. I tried something like this but it doesn’t
work because Rails wants an instance variable to bind to. How do I
properly bind my array?

<% @shopping_list.items.each do |item| %>

<%= text_field("shopping_list.items[" + + "].quantity", item.quantity, :size => 3) %> <%= (Product.find item.product_name_id).name%> <% end %>

I meant to post this to the Rails mailing list not this one. Sorry.
Please don’t respond to the list but rather to me personally.