Hidden Field in Simple Nested Form Not Being Submitted

Question

Environment: Rails 3.1.0, Ruby 1.9.2

I have Portfolio model which has_many Positions which has_one Asset.

This is the schema for the Position model:

create_table "positions", :force => true do |t|
    t.integer  "portfolio_id"
    t.integer  "asset_id"
    t.decimal  "holding_percentage"
end

When the user creates a portfolio he/she should enter the portfolio name and then add positions by adding stock tickers. Jquery does its stuff and shows the full name of the asset and also inserts the asset_id into the hidden field.

I am using both nested_form and simple_form as follows:

<%= simple_nested_form_for @portfolio  do |f| %>

    <%= f.input :name, :placeholder => 'Your portfolio name' %>  

    <%= f.fields_for :positions do |position_form| %>

        <%= text_field_tag 'asset-ticker', nil, :class => 'asset-ticker' %>         
        <span class="asset-name"></span>
        <%= position_form.text_field :holding_percentage, :class => 'asset-perc' %>
        <%= position_form.hidden_field :asset_id, :class => 'asset-num', :as => :hidden %>

        <%= position_form.link_to_remove "Remove this position", :class => 'asset-rem-link' %>
    <% end %>

    <p><%= f.link_to_add "Add a Position", :positions, :class => 'asset-add-link' %></p>  

    <%= f.button :submit %>

<% end %>

The problem is that the asset_id value in the hidden field is not being submitted. The parameters look as follows:

Parameters: {"utf8"=>"✓", "authenticity_token"=>"hmvoGHF9GzpPsohQQ2MwhWk4FzhVVrf+IqoChHgftEs=",  
    "portfolio"=>{"name"=>"needhelpnow", 
                  "positions_attributes"=>
    {"new_1316730954406"=>{"holding_percentage"=>"11", "asset_id"=>"", "_destroy"=>"false"}, 
     "new_1316730961085"=>{"holding_percentage"=>"22", "asset_id"=>"", "_destroy"=>"false"}, 
     "new_1316730971587"=>{"holding_percentage"=>"33", "asset_id"=>"", "_destroy"=>"false"}}}, 
     "commit"=>"Create Portfolio"}

Answer 1

It turns out that the problem was that I was writing in the value of the hidden field with:

('.asset-num').html(data.id)

Instead of:

('.asset-num').val(data.id)