gistfile1.rb

module Web::AdsHelper
  def add_picture(form)
    link_to_function 'Adicionar outra imagem' do |page|
      form.fields_for :pictures, Picture.new, :child_index => 'NEW_RECORD' do |f|
        html = render(:partial => 'fields_pictures', :locals => {:f => f})
        # caso use prototype, inserir a linha abaixo
        # $('pictures').insert({ bottom: "#{ escape_javascript html }".replace(/NEW_RECORD/g, new_picture_id) });
        page << %{
          var new_picture_id = new Date().getTime()
          $('#pictures').after("#{escape_javascript html}".replace(/NEW_RECORD/g, new_picture_id));
        }
      end
    end
  end
end