带有Rails的jQuery扩展表单不起作用

Question

我按照this guide将此功能实施到我的应用

但它不能正常工作，当我点击按钮进行克隆并添加字段时它什么都不做，但当我自动加载页面时，它会克隆一个而且不会更多。

我已经尝试了usig j2.coffee，尝试将文件更改为.js，每一个简单的事情，但没有一个工作，

= _form.html.erb代码

<%= form_for(@task) do |f| %>
<% if @task.errors.any? %>
  <div id="error_explanation">
  <h2><%= pluralize(@task.errors.count, "error") %> prohibited this task from being saved:</h2>

  <ul>
  <% @task.errors.full_messages.each do |message| %>
    <li><%= message %></li>
    <% end %>
     </ul>
   </div>
  <% end %>
  <table >
   <thead>
   <tr>
   <th> <%= f.label :projeto_id, "Projeto da Atividade" %><br> </th>
  <th> <%= f.label :seq, "Raiz Sequencial" %><br> </th>
   <th> <%= f.label :descr, "Descrição da Atividade" %><br> </th>
   <th> <%= f.label :seqpai, "Ramo Sequencial" %><br> </th>
<th>  <%= f.label :hour, "Horas de Execução" %> </th>
<th>  <%= f.label :typo, "Tipo da Atividade" %><br> </th>
</tr>
</thead>
<tbody id="jqueryform">
<tr name="tr">
<td name="projetoid"> <%= f.grouped_collection_select :projeto_id,     Cliente.order(:name), :projetos, :name, :id, :name, prompt: "Selecionar" %>       </td>
<td name="raiz">     <%= f.number_field :seq %>  </td>
<td name="descr">    <%= f.text_field :descr %> </td>
<td name="seqpai">  <%= f.number_field :seqpai %>  </td>
<td name="hour">    <%= f.number_field :hour %> </td>
<td name="typo">   <%= f.select("typo", {"Analitica" => "Analitica",     "Sintetica" => "Sintetica"}) %> </td>
   </tr>
  </tbody>
    </table>

   <br>
  <span id="writeroot"></span>
   <br>

    <input type="button" id="moreFields" value="Adicionar Atividade!" />
    <br><br><br>
    <%= f.submit 'Enviar', class: 'btn btn-primary btn-lg' %>

    <% end %>

我的tasks.js.coffee代码

counter = 0

moreFields = ->
  counter++
  newFields = document.getElementById('jqueryform').cloneNode(true)
  newFields.id = ''
  newFields.style.display = 'block'
  newField = newFields.childNodes
  i = 0
  while i < newField.length
    theName = newField[i].name
    if theName
      newField[i].name = theName + counter
    i++
  insertHere = document.getElementById('writeroot')
  insertHere.parentNode.insertBefore newFields, insertHere
  return

window.onload = moreFields