def new
    @questions = Question.find_all_by_survey_id(params[:survey_id])
    @answers = @questions.map{|q| q.answers.build}

    respond_to do |format|
      format.html # new.html.erb
      format.xml  { render :xml => @answer }
    end
  end

Started GET "/surveys/1/answers/new" for 127.0.0.1 at 2010-10-21 20:24:59 -0400
  Processing by AnswersController#new as HTML
  Parameters: {"survey_id"=>"1"}
  User Load (2.4ms)  SELECT `users`.* FROM `users` WHERE (`users`.`id` = 2) LIMIT 1
  Question Load (0.4ms)  SELECT `questions`.* FROM `questions` WHERE (`questions`.`survey_id` = 1)
  Question Load (0.4ms)  SELECT `questions`.* FROM `questions` WHERE (`questions`.`id` = 1) LIMIT 1
  Question Load (0.2ms)  SELECT `questions`.* FROM `questions` WHERE (`questions`.`id` = 3) LIMIT 1
  Question Load (0.1ms)  SELECT `questions`.* FROM `questions` WHERE (`questions`.`id` = 5) LIMIT 1
  Question Load (0.2ms)  SELECT `questions`.* FROM `questions` WHERE (`questions`.`id` = 7) LIMIT 1
  Question Load (0.2ms)  SELECT `questions`.* FROM `questions` WHERE (`questions`.`id` = 9) LIMIT 1
Rendered answers/_form.html.haml (28.1ms)
Rendered answers/new.html.haml within layouts/application (43.5ms)
Completed 200 OK in 182ms (Views: 50.7ms | ActiveRecord: 3.9ms)

New.html.haml
%h1 New answer
= render 'form'

_form.html.haml
= form_for 'answers[]', :url => survey_answers_path do |f|
  - for answer in @answers
    = fields_for 'answers[]', answer do |a|
      %p= answer.question.question_string
      = a.label :answer_string
      = a.label answer.question_id
      = a.text_field :answer_string
  .actions
  = f.submit

class Answer < ActiveRecord::Base
  belongs_to :question
  belongs_to :user
  belongs_to :survey
  attr_accessible :answer_string, :user_id, :question_id
end

class Question < ActiveRecord::Base
  belongs_to :survey
  attr_accessible :question_string, :question_type
  validates_presence_of :question_string, :question_type
  has_many :answers, :dependent => :destroy
end

class Survey < ActiveRecord::Base
  has_many :questions, :dependent => :destroy
  has_many :answers, :through => :questions
  belongs_to :user
  validates_presence_of :name, :user_id
  accepts_nested_attributes_for :questions, :allow_destroy => true
  accepts_nested_attributes_for :answers, :allow_destroy => true
end