Problem with Railscast #197 - Nested Model Form Part 2

Question

I'm trying to implement Ryan's Railscast #197 in a system with Questions, Answers, and (multiple choice) Options. http://railscasts.com/episodes/197-nested-model-form-part-2.

I have successfully implemented the nesting among these forms/partials.
The simpler 'check box' way to delete records works properly.
The problem occurs when I try to add/delete records.

I have copied the code exactly as it appears in his Railscast:

#new.html.erb
<%= javascript_include_tag :defaults, :cache => true %>
<% f.fields_for :in_options do |builder| %>
  <%= render "option_fields", :f => builder %>
<% end %>

#_option_fields.html.erb partial
<%= f.hidden_field :_destroy %>
<%= link_to_function "remove", "remove_fields(this)" %>

#application_helper.rb (exact same as #197)
  def link_to_remove_fields(name, f)
    f.hidden_field(:_destroy) + link_to_function(name, "remove_fields(this)")
  end

  def link_to_add_fields(name, f, association)
    new_object = f.object.class.reflect_on_association(association).klass.new
    fields = f.fields_for(association, new_object, :child_index => "new_#{association}") do |builder|
      render(association.to_s.singularize + "_fields", :f => builder)
    end
  link_to_function(name, h("add_fields(this, \"#{association}\", \"#{escape_javascript(fields)}\")"))
  end

#application.js (exact same as #197. I have an Event.addbehavior below this code.)
function remove_fields(link) {
  $(link).previous("input[type=hidden]").value = "1";
  $(link).up(".fields").hide();  
}

function add_fields(link, association, content) {
  var new_id = new Date().getTime();
  var regexp = new RegExp("new_" + association, "g")
  $(link).up().insert({
    before: content.replace(regexp, new_id)
  });
}

2 problems:

When I click on the 'remove' link it doesn't remove - it just shifts the page up or down.
When I include link_to_add_fields "Add Answer", f, :answers, I get undefined method `klass' for nil:NilClass.

------PROGRESS------

If I move function remove_fields(link) to the top of new.html.erb, the remove link works. Which means, I have a problem accessing the function in my application.js. Here's my condensed structure.

# layout forms.html.erb
<html>
  <head>    
    <%= stylesheet_link_tag "global", "forms", "candidateCreateProfile", "LiveValidation", "formsAccount", :cache => true %>
    <%= javascript_include_tag :defaults, "LiveValidation" %>
  </head>
  <body>
    <%= yield %>
  </body>
</html>

# new.html.erb
<%= stylesheet_link_tag "interviewQuestions" %>
<%= javascript_include_tag "effects", "lowpro", "toggle", :cache => true %>
...#everything else, including my call to remove_fields

here is the solution: http://stackoverflow.com/questions/8895193/rails-3-and-jquery-railscast-197-issues — suely, Mar 05 '12 at 18:15

score 3 · Answer 1 · edited May 23 '17 at 12:30

3

For those who still have undefined method `klass' for nil:NilClass issue see the following thread — has_many :through nested_form that can build multiple instances

edited May 23 '17 at 12:30

Community

1
1

answered May 19 '11 at 07:52

jibiel

8,175
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score 1 · Answer 2 · answered Mar 30 '13 at 13:35

1

Just stumpled upon this question - if it helps, use this awesome nested form gem by Ryan Bates.

Here's the railscast.

answered Mar 30 '13 at 13:35

Dennis Hackethal

13,662
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score 0 · Answer 3 · answered Oct 01 '13 at 12:53

0

In my case the javascript wasn´t called so, I change the request for:

link_to name, '#', onclick: "add_fields(this,'#{association}','#{escape_javascript(fields)}')";

answered Oct 01 '13 at 12:53

user2834919

1

score 0 · Answer 4 · answered Jan 14 '14 at 03:23

0

You are using a prototype library syntax instead of jQuery. Visit the episode page, and look for the code used part where both prototype and jQuery syntaxes are provided.

answered Jan 14 '14 at 03:23

alucillo36

91
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score 0 · Answer 5 · answered Jun 18 '10 at 16:05

0

Have you made sure app...js is being included in the output? You may need to edit your layout.

answered Jun 18 '10 at 16:05

thomasfedb

5,990
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I have <%= stylesheet_include_tag :defaults %> in my layout, which is called 'forms'. application.js is stored in /public/javascripts. – sscirrus Jun 18 '10 at 18:37
open up the page source and check it's being included, you might be using the wrong layout for that controller/action ? – thomasfedb Jun 19 '10 at 07:46

Problem with Railscast #197 - Nested Model Form Part 2

5 Answers5