Loading a template via Ajax - Error - ruby-on-rails

Question

I have this form that I want to load via AJAX into the video show view:
<%= form_for #video, :url => {:action => "update"}, :remote => true do |f| %>
<div class="field">
<%= f.text_field :topic_names, :class => "topic_field" %>
</div>
<%= f.submit "Add Topic" %>
<% end %>
I have this link in the video show view that when clicked, I want it to render the form:
<%= link_to "Add Topics", new_topicable_path(#topicable, :format => :js), :remote => true, :id => 'edit_topics_link' %>
I put the form in topicables/new.html.erb and I have topicables/new.js.erb file which has:
$("<%= escape_javascript render(:file => 'topicables/new.html.erb') %>").insertAfter('.topic_holder');
$('#edit_topics_link').hide();
Now when I click the link, I get an error in my logs. This is what my logs show:
Started GET "/topicables/new.js" for 127.0.0.1 at Sat Apr 02 03:58:52 -0700 2011
Processing by TopicablesController#new as JS
Rendered topicables/new.html.erb (0.7ms)
Rendered topicables/new.js.erb (2.6ms)
Completed in 15ms
ActionView::Template::Error (undefined method `model_name' for NilClass:Class):
1: <%= form_for #video, :url => {:action => "update"}, :remote => true do |f| %>
2: <div class="field">
3: <%= f.text_field :topic_names, :class => "topic_field" %>
4: </div>
app/views/topicables/new.html.erb:1:in `_app_views_topicables_new_html_erb___1876131309_2172772700_0'
app/views/topicables/new.js.erb:1:in `_app_views_topicables_new_js_erb__1367015167_2172792200_0'
Rendered /Library/Ruby/Gems/1.8/gems/actionpack-3.0.4/lib/action_dispatch/middleware/templates/rescues/_trace.erb (1.1ms)
Rendered /Library/Ruby/Gems/1.8/gems/actionpack-3.0.4/lib/action_dispatch/middleware/templates/rescues/_request_and_response.erb (92.5ms)
Rendered /Library/Ruby/Gems/1.8/gems/actionpack-3.0.4/lib/action_dispatch/middleware/templates/rescues/template_error.erb within rescues/layout (98.9ms)
What's going on? How can I fix this error to make the AJAX rendering of the form work?

Answer 1

This is basically telling you that #video is not defined. If that's the case you can either define it in your new method or use :video which creates a new instance variable rather than looking for one in the page context. Then you can handle the find and update in the update method.
Edit: jQuery load method
$("#myButton").click(function(){
$("#target").load("/topicables/new #new_topicable");
});