title: Thymeleaf setting model field with th:field on button dropdown not working
body: <p>I am trying to set the field on my model object using thymeleaf in a form.
  setting th:field on the button is giving back all null properties. They are all formatted the same but this is the look:</p>
  
  <pre><code>&lt;div class="dropdown"&gt;
      &lt;button th:field="*{product}" class="btn grey-dropdown dropdown-toggle" type="button"
      data-toggle="dropdown"&gt;(Select)&lt;span class="caret"&gt;&lt;/span&gt;
      &lt;/button&gt;
          &lt;ul class="dropdown-menu filter-dropdown-items"&gt;
              &lt;li th:each="product : ${products}"&gt;&lt;a&gt;&lt;span 
  th:text="${product}" th:remove="tag"&gt;&lt;/span&gt;&lt;/a&gt;&lt;/li&gt;
          &lt;/ul&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>Am I doing something wrong? The post comes back with null fields.</p>