NoMethodError using Rails 4.0 and nested forms with cocoon - ruby-on-rails

Question

I'm learning to use Rails 4.0 and I'm using Cocoon to create nested forms for a simple Polling app.
The user should be able to add a new question and then add as many answers as they'd like.
I've got the nested forms working but when I try to save the Poll and i'm getting an error that says NoMethodError in PollsController#create - undefined method ``answer' for #<Poll:0x007fba59a70dd0>
Here's the relevant information from my Polls_Controller:
before_action :set_poll, only: [:show, :edit, :update, :destroy]
def create
#poll = Poll.new(poll_params)
respond_to do |format|
if #poll.save
format.html { redirect_to #poll, notice: 'Poll was successfully created.' }
format.json { render :show, status: :created, location: #poll }
else
format.html { render :new }
format.json { render json: #poll.errors, status: :unprocessable_entity }
end
end
end
private
def poll_params
params.require(:poll).permit(:question, :expires, answers_attributes: [:id, :answer, :_destroy])
end
Polls Model
class Poll < ActiveRecord::Base
has_many :answers, :class_name => "Answer"
accepts_nested_attributes_for :answers, reject_if: :all_blank, allow_destroy: true
validates :answer, presence: true
end
And the Answers model
class Answer < ActiveRecord::Base
belongs_to :poll
end
Here are the two .erb partials containing the Poll form and the Answer (nested) form.
_form.html.erb
<%= form_for(#poll) do |f| %>
<% if #poll.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#poll.errors.count, "error") %> prohibited this poll from being saved:</h2>
<ul>
<% #poll.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="form-group">
<%= f.label :question %><br>
<%= f.text_field :question, class: "form-control" %>
</div>
<div class="form-group" id="answers">
<%= f.fields_for :answers do |answer| %>
<%= render 'answer_fields', f: answer %>
<% end %>
<div class="links">
<%= link_to_add_association 'Add Answer', f, :answers, class: "btn btn-default add-button" %>
</div>
</div>
<div class="form-group">
<%= f.label :expires %><br>
<%= f.datetime_select :expires %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
_answer.html.erb
<div class="nested-fields form-group">
<div class="field">
<%= f.label :answer %>
<br/>
<%= f.text_field :answer, class: "form-control" %>
</div>
<%= link_to_remove_association "remove answer", f, class: "form-button btn btn-default" %>
</div>
I've been staring at this for far too long and even though it's a simple idea, my brain isn't seeing the issue. Any ideas?
Edit Here is my Schema
ActiveRecord::Schema.define(version: 20151104213600) do
create_table "answers", force: :cascade do |t|
t.text "answer"
t.integer "poll_id"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
add_index "answers", ["poll_id"], name: "index_answers_on_poll_id"
create_table "polls", force: :cascade do |t|
t.string "question"
t.datetime "expires"
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
end
end

Answer 1

I have run into this problem myself, and by pre-building the associated relation, it worked like a charm, doing this:
def new
#poll = Poll.new
#poll.answers.build
end