title: SmartGWT: Unable to check a value of a SelectItem
body: <p>I am facing an issue whereby I am unable to check from the values populated in a SelectItem.</p>
  
  <pre class="lang-java prettyprint-override"><code>DataSource ds = Datasource.get("users");
  
  SelectItem selectItem = new SelectItem("Select One");
  selectItem.setRequired(true);
  selectItem.setAllowEmptyValue(false);
  selectItem.setOptionDataSource(ds);
  selectItem.setDisplayField("username");
  
  myDynamicForm.setFields(selectItem);
  </code></pre>
  
  <p>The SelectItem is populated with the items in the datasource and displays the options correctly with the "username" field. But I am unable to select any option other than the first one. I am not sure if I am missing anything. Appreciate any help.</p>