Reject_if not working

I have some troubles with :reject_if. I don't know why the following code doesn't work.

View - _form.html.erb:

<%= f.fields_for :questions do |builder| %>
  <div class="nested-field">
    <%= builder.label :id, "Question" %><br />
    <%= builder.collection_select(:id, Question.all(:order => 'question'), :id, :question, { :prompt => 'Select Question' } ) %>
  </div>
  <div class="nested-field">
    <%= builder.label :test1 %><br />
    <%= builder.text_field :test1 %>
  </div>
  <div class="nested-field">
    <%= builder.label :test2 %><br />
    <%= builder.text_field :test2 %>
  </div>
  <div class="nested-field">
    <%= builder.label :description %><br />
    <%= builder.text_field :description 开发者_高级运维%>
  </div>
  <br /><br /><br />
  <hr />
<% end %>

Model - questionary.rb:

has_many :questions, :dependent => :destroy
accepts_nested_attributes_for :questions, :reject_if => lambda { |a| a[:id].blank? }, :allow_destroy => true

Thank you very much!

Instead of

:reject_if => lambda { |a| a[:id].blank? }

try

:reject_if => lambda { |a| a['id'].blank? }

(note the string 'id') and to follow the API exactly, use proc

:reject_if => proc { |a| a['id'].blank? }

I had a look at the API for accepts_nested_attributes_for, and found there that the documentation states:

:reject_if Allows you to specify a Proc or a Symbol pointing to a method that checks whether a record should be built for a certain attribute hash.

Have you tried to replace the lambda with proc? The syntax here seems to be special, so the lambda may be just ignored.