How to use Nested Attributes in Rails 3 Forms

For example, say we want to add multiple addresses(attributes) having many fields inside a create/edit employee form

Step# 1

•         Create a model named Employee

•         Create another model named Address

•         Add the following relationship in Employee model

class Employee < ActiveRecord::Base
has_many :addresses, :dependent => :destroy
accepts_nested_attributes_for :addresses, :reject_if => lambda { |a| a[:city].blank? }
end

•    Nested attribute form rejects if the city field of the address is blank

Step# 2

•        In Employees controller add the following in the “new” action

def new
@employee = Employee.new
@employee.addresses << Address.new
end

Step# 3

•         In the view file add the following inside the form attribute

<%= form_for @employee, :html => { :multipart => true, :id => 'new-employee' } do |f|
<%= f.label :name, 'Name' %>
<%= f.text_field :name %>
 
<% end %>