How to set different id in nested form attributes

Hi people.

I'm developing a rails 3.0.9 app, I'm using "accept nested attributes
for" to add dynamically new "child" items to its parent. the thing is
every child has the same id, and I need every child with its own id,
because I need to make some jquery functions to work with them.

Is there a way to achieve this?

Tanks for your help

How did all the children end up with the same ID?

Posting some of your problematic code can help us help you.

I presume you are talking about the id in the html rather than the id
of the record in the database. When you generate the html for the
child, just allocate a new id for each. Since you have not shown us
how you generate the html it is difficult to comment.


Yes, I'm not saying that the DB id is the same, I'm saying the html
attribute "id" is the same, sorry for that.
But I don't know how to set a different id for each child.

I'm using nested attributes in this way, to simplify I will use
"document" and "products", where a "document" has many "products":


class Document < ActiveRecord::Base
  has_many :details,:class_name => 'Product', :foreign_key =>
'document_id', :dependent => :destroy
  accepts_nested_attributes_for :details, :allow_destroy => :true


class Product < ActiveRecord::Base
  belongs_to :document :foreign_key => 'document_id'


class DocumentsController < ApplicationController

  def index...

  def show...

  def new
    @document =
    respond_to do |format|
      format.html # new.html.erb
      format.xml { render :xml => @document }



<%= form_for @document do |f| %>

(document fields such as number, provider, date, etc)

                <div class="details">
                <% if %>
                  <%= f.fields_for :details do |d| %>
                    <%= render "details", :f => d %>
                  <% end %>
                <% end %>
                <%= link_to_add_fields "+ Add Product", f, :details %>
(button for "submit")

<% end %>


<div class="fields">

    <%= f.label :product %>&nbsp;
    <%= f.collection_select(:document_id, Document.all, :id, :number,
options = {:prompt => ''},:class => '_prod select sbig') %>

    <%= link_to_remove_fields "remove product", f %>



module ApplicationHelper
  def link_to_remove_fields(name, f)
    f.hidden_field(:_destroy) + link_to_function(name,

def link_to_add_fields(name, f, association)
    new_object =
    fields = f.fields_for(association, new_object, :child_index =>
"new_#{association}") do |builder|
      render(association.to_s.singularize, :f => builder)
    link_to_function(name, ("add_fields(this, '#{association}',


function remove_fields(link) {

function add_fields(link, association, content) {
  var new_id = new Date().getTime();
  var regexp = new RegExp("new_" + association, "g")
  $(link).parent().before(content.replace(regexp, new_id));

So, in _details, I didn't set an id (html attribute) for product but
If I check with firebug, The id is the same for each "detail", if I
try to set manually, obviously, each "detail" get the same id.

Please, help me

I already solve this

I'm really sorry, I've just realized that every child had its own
"id", so it was easier to get it solved.

Thanks for your help and for sharing your time