How to implement horizontal tabs menu using JQuery UI tabs, fetching content through Ajax, from a Rails server.

Steps:
1. Create the Rails app, use the -d option to set the database adaptor.
    rails -d postgresql rails_jquery_ajax_tabs

2. Setup controller and views to be tabbed.
    script/generate controller about tab1 tab2 tab3 tab4

3. Download and add jquery.js, jquery-ui.js to the rails app directory public/javascripts and jquery-ui stylesheet to public/stylesheets,
    from http://jqueryui.com/download

4. Create layout with jquery javascript files and stylesheet.
    - add jquery stylesheet to layout
    <%= stylesheet_link_tag "jquery-ui-1.7.2.custom", :cache => true %>
    - add jquery javascript files to layout (both core and ui) and also application.js
    <%= javascript_include_tag "jquery-1.3.2.min", "jquery-ui-1.7.2.custom.min", "application" %>

5. setup up tabs markup in layout,
    match the link 'title' attribute and the content container's id, otherwise jquery dynamically creates the container.
    Using links pointing to the server instead of named anchors inside the same document causes jquery ui tabs to ajaxify the tabs behavior.

    <div id="tabs">
      <ul>
        <li><%= link_to content_tag(:span, "Tab1"), {:controller => "about", :action => "tab1"}, {:title => "main_content"} %></li>
        <li><%= link_to content_tag(:span, "Tab2"), {:controller => "about", :action => "tab2"}, {:title => "main_content"} %></li>
        <li><%= link_to content_tag(:span, "Tab3"), {:controller => "about", :action => "tab3"}, {:title => "main_content"} %></li>
      </ul>
    </div>
    <div id="main_content">
      <%= yield %>
    </div>

6. Create jquery tabs in application.js
    $(document).ready(function(){
        $("#tabs").tabs();
    });

7. create tab content views in views/about/ e.g. tab1.html.erb :
<h1>About#tab1</h1>
<p>Find me in app/views/about/tab1.html.erb</p>

8. turn off layout in controller if request.xhr?

  layout :determined_by_request
 
  protected
 
  def determined_by_request
    if request.xhr?
      return false
    else
      'application'
    end
  end

7. set up routes in config/routes.rb:

  map.root :controller => "about", :action => "tab1"

References:
http://docs.jquery.com/UI/Tabs
http://jqueryui.com/demos/tabs/
Similar implementation using prototype: http://www.eduvoyage.com/2008/9/26/ajax-tabs-and-rails and http://www.eduvoyage.com/2009/3/14/ajax-tabs-and-rails-2