Problem with collection_select

Hi all.

I have a problem with collection_select, hope you guys can help me.

User has one Address, and Address has one Province. Here are my models :


class User < ActiveRecord::Base   has_one :address, :dependent => :destroy ...


class Address < ActiveRecord::Base   has_one :province   belongs_to :user ...


class Province < ActiveRecord::Base   belongs_to :country, :address ...

I need to populate a select tag contains list of all provinces. How can I do that? I've tried use collection_select but isn't working.

Thank you.