Why is accepts_nested_attributes_for not working for me? (rails 3)

问题

I'm using formtastic and haml on a Rails 3 application. I'm trying to make a nested form for surveys and questions, but it's just not working for me. I've watched the railscast and on it and everything, but I can't seem to make it work for my application. So right now, I have the following:

models

class Survey < ActiveRecord::Base
  attr_accessible :intro, :name, :pubdate, :enddate, :pubid

  belongs_to :user
  has_many :questions, :dependent => :destroy, :autosave => true

  accepts_nested_attributes_for :questions, :allow_destroy => true
end

class Question < ActiveRecord::Base

  belongs_to :survey
  has_many :answers, :dependent => :destroy

  attr_accessible :q_text, :order, :q_type

end

relevant controller method

def update
  @survey = Survey.find(params[:id])
  @user = current_user
  if check_auth_and_redirect @user, @survey
    if @survey.update_attributes(params[:survey])
      flash[:success] = "Survey Updated"
      redirect_to edit_survey_path(@survey)
    else
      @title = "Editing Survey #{@survey.id}"
      render 'edit'
    end
  end
end

views

= semantic_form_for @survey do |f|
  = render "shared/survey_inputs", :object => f
  = f.inputs :for => :questions, :name => "Survey Questions" do |fq|
    %hr
    = fq.input :q_text, :label => "Question text"
    = fq.input :q_type, 
               :label => "Question type", 
               :as => :select,
               :collection => %w(text scale radio select)
    = fq.input :order, :label => "Question order"

The form renders correctly, but when I change a question and click save, the records doesn't reflect my changes. I do have debug(params) turned on, and here is what it comes back as:

--- !map:ActiveSupport::HashWithIndifferentAccess 
      utf8: "\xE2\x9C\x93"
      _method: put
      authenticity_token: CJCc9LvdoPjxwGJkhUnZjR0Z/c5Wt5VBT3bBr/wB4+A=
      survey: !map:ActiveSupport::HashWithIndifferentAccess 
        name: This is my survey
        intro: I've got a lovely bunch of coconuts. There they are all standing in a row.
        pubid: smargdab
        pubdate(1i): ""
        pubdate(2i): ""
        pubdate(3i): ""
        enddate(1i): ""
        enddate(2i): ""
        enddate(3i): ""
        questions_attributes: !map:ActiveSupport::HashWithIndifferentAccess 
          "0": !map:ActiveSupport::HashWithIndifferentAccess 
            q_text: one one one one one one one one one one one
            q_type: text
            order: "3"
            id: "1"
          "1": !map:ActiveSupport::HashWithIndifferentAccess 
            q_text: 2 2 2 2 2 2 2 2 2 2
            q_type: text
            order: "1"
            id: "2"
          "2": !map:ActiveSupport::HashWithIndifferentAccess 
            q_text: 3 3 3 3 3 3 3 3 3 3
            q_type: text
            order: "2"
            id: "3"
      commit: Update Survey
      action: update
      controller: surveys
      id: "2"

What am I doing wrong here? I don't want to have to write these attribute changers manually!

回答1:

I am looking at some old code of mine that uses accepts_nested_attributes_for and I think what you need to do is change

attr_accessible :intro, :name, :pubdate, :enddate, :pubid

attr_accessible :intro, :name, :pubdate, :enddate, :pubid, :questions_attributes

回答2:

I was not allowing certain things in attr_accessible. Problem is, I don't know what to allow. I think it's questions_attributes, but it doesn't seem to work that way.

来源：https://stackoverflow.com/questions/3765810/why-is-accepts-nested-attributes-for-not-working-for-me-rails-3

标签

ruby-on-rails

haml

formtastic