gistfile1.rb

# teams/new.html.haml
-form_for([@team]) do |f| 
 
... 
 
%p= link_to_function "Add a Member"; do |page| 
  page.insert_html :bottom, :members, :partial =>'member', :object => Member.new 
  = f.submit 
 
# teams/_member.html.haml
- fields_for "team[member_attributes][bar]", member do |f| 
  = f.datetime_select  :arrival 
  
# teams_controller.rb
def create 
  @team = Team.new(params[:team]) 
  @members = @team.members 
end 
 
# models/team.rb
def member_attributes=(attributes) 
  [attributes["fu"]].each do |a| 
    members.build(a) 
  end 
end