ruby on rails - Empty associations for fields_for if the content is added dynamically via jquery -

i built form_for 4 associated models. created nested fields_for can added dynamically code below. form works if call 'edit' method if use method below add new data fields_for remains empty , not shown.

def link_to_add_fields(name, f, association)     new_object = f.object.send(association).klass.new     id = new_object.object_id     fields = f.fields_for(association, new_object, child_index: id) |builder|       render(association.to_s.singularize + "_fields", f: builder)     end     link_to(name, '#', class: "add_fields", data: {id: id, fields: fields.gsub("\n", "")})   end 

this works fine if wants add 1 form of model. if added content have fields_for nested fields_for text_fields not created. in opinion because not build associations. how can fix method this?

i have similar method (based on itay grudev's blog post), in set child_index nil , use jquery replace timestamp (so many records can added avoiding them having same id).

so, in application_helper.rb file i've got:

def link_to_add_fields(name = nil, f = nil, association = nil, options = nil, html_options = nil, &block)      f, association, options, html_options = name, f, association, options if block_given?      options = {} if options.nil?      html_options = {} if html_options.nil?       if options.include? :locals        locals = options[:locals]     else        locals = { }      end      if options.include? :partial        partial = options[:partial]      else        partial = association.to_s.singularize + '_fields'     end       new_object = f.object.class.reflect_on_association(association).klass.new      fields = f.fields_for(association, new_object, child_index: nil) |builder|        render(partial, locals.merge!( fields: builder))      end       html_options['data-form-prepend'] = raw cgi::escapehtml( fields )      html_options['href'] = '#'      content_tag(:a, name, html_options, &block)  

end

and added coffeescript file called dynamic_tables.js.coffee in find newly added fields, replace name timestamp (so they're indexed group) , prepend form target (a hidden element added @ bottom of table , marked prepend_target). i've got:

$('[data-form-prepend]').click (e) ->     target = $($(this).attr('prepend_target'))     obj = $($(this).attr('data-form-prepend'))     current_time = (new date).gettime()     obj.find('input, select, textarea').each ->       $(this).attr 'name', ->         $(this).attr('name').replace 0, current_time       return     obj.insertbefore target     false 

that should trick. hope helps.