To use Active with scaffold with JRails you have to use a different
JQUERY_VAR than $
In our controllers
1. set
ActionView::Helpers::PrototypeHelper::JQUERY_VAR = ‘jQuery’
or
ActionView::Helpers::PrototypeHelper.const_set(:JQUERY_VAR, 'jQuery')
2. in your layout load both prototype and jquery
<%= javascript_include_tag ‘prototype’, ‘effects’, ‘jquery’ %>
3. Lastly, make sure to tell jQuery to not conflict with Prototype over $ in your Javascript:
application.html.erb
<script type="text/javascript">
jQuery.noConflict();
</script>
Now, you should use "jQuery()" instead of "$()".
eg:
jQuery("#id").hide()
http://errtheblog.com/posts/73-the-jskinny-on-jquery