Rails, jQuery, Ajax create and update.js.erb

Question

Alright. I am working with RoR and jQuery and I have already got my update and create links working and functioning with their .js.erb files. The problem arises when in create with this line of code.

#create.js.erb
$("#promo_types").append("<%= escape_javascript(render(:partial => "promotion_type"))%>");

it is throwing an error: You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.each

#index.erb
<div id="promo_types">
  <%= render :partial => "promotion_type" %>
</div>

#_promotion_type
 <% @promotion_types.each do |@promotion_type| %>
<table>
    <tr>
      <td width="200"><%=h @promotion_type.name %></td>
      <td width="20"><a class="Edit<%=h @promotion_type.id %>" href="#"><img src="/images/pencil.png" alt="Edit" title="Edit"  /></a></td>
      <td width="20"><%= link_to(image_tag('/images/bin.png', :alt => 'Remove', :title => "Remove"), @promotion_type, :class => "deleteCategory") %></td>
    </tr>
    </table>
     <div id="popupEdit<%=h @promotion_type.id %>" class="popupEdit">
    <a class="popupClose<%=h @promotion_type.id %>" id="popupClose">x</a>
    <%= render :file => 'promotion_types/edit' %></div>
  <% end %>

It doesn't like that first line of code of the partial when I try to append the row using ajax.

My only other question is concerning my update.js.erb. I works fine. If i click edit and update it updates the changes, but I don't see them till I refresh the page. I don't want to .append the partial because the would add the edit to the bottom of the list. Do I use a .html to refresh my partial thru AJAX?

EDIT:

#full create.js.erb

$("#promo_types").append(<% escape_javascript(render(:partial => "promotion_type"))%>");
  $("new_promotion_type")[0].reset();
  $(".addtoggle01").toggle();
  $(".addtoggle01").before('<div id="notice">Your promotion type has been successfully submitted.</div>');

It resets my form, hides the form, and displays the notice, but it isn't appending anything and not throwing any errors either.

Answer 1

In your _promotion_type partial you are looping through @promotion_types and it sounds like this instance variable is not getting set in the create action.

From the name, it sounds like that partial should only display one promotion type, not many. So move the loop outside of the partial. I recommend using the :collection and :object options to pass the model to the partial.

# index.html.erb
<div id="promo_types">
  <%= render :partial => "promotion_type", :collection => @promotion_types %>
</div>

# _promotion_type.html.erb
<table>
  <tr>
    <td width="200"><%=h promotion_type.name %></td>
    <td width="20"><a class="Edit<%=h promotion_type.id %>" href="#"><img src="/images/pencil.png" alt="Edit" title="Edit"  /></a></td>
    <td width="20"><%= link_to(image_tag('/images/bin.png', :alt => 'Remove', :title => "Remove"), promotion_type, :class => "deleteCategory") %></td>
  </tr>
</table>
<div id="popupEdit<%=h promotion_type.id %>" class="popupEdit">
<a class="popupClose<%=h promotion_type.id %>" id="popupClose">x</a>
<%= render :file => 'promotion_types/edit' %></div>

# create.js.erb
$("#promo_types").append("<%= escape_javascript(render(:partial => "promotion_type", :object => @promotion_type))%>");

As for your second question, yes. You can assign a specific ID to each record and replace that using the .html method.

# update.js.erb
$("#promo_type_<%= @promotion_type.id %>").html("<%= escape_javascript(render(:partial => "promotion_type", :object => @promotion_type))%>");