title: how to localize DateLabel and NumberLabel customFormat attribute?
body: <p>I am in the process of localizing a rather large GWT UIbinder code base and ran across a couple of instances where the process of setting attributes does not work.</p>
  
  <p><a href="http://google-web-toolkit.googlecode.com/svn/javadoc/2.4/com/google/gwt/user/client/ui/DateLabel.html" rel="nofollow">DateLabel javadoc</a></p>
  
  <p><a href="http://google-web-toolkit.googlecode.com/svn/javadoc/2.4/com/google/gwt/user/client/ui/NumberLabel.html" rel="nofollow">NumberLabel javadoc</a></p>
  
  <p>I need to specify the date format and number format in a LocalizableResource_xx.properties file for  DateLabel and NumberLabel widgets.</p>
  
  <p>I tried converting this fragment </p>
  
  <pre><code>   &lt;g:DateLabel styleName="{style.formPromptData}" 
          ui:field="createDate" customFormat="MMM d, yyyy" /&gt; 
  </code></pre>
  
  <p>using <a href="https://developers.google.com/web-toolkit/doc/latest/DevGuideUiBinderI18n#HTML_attributes_that_need_translation" rel="nofollow">the ui:attribute method</a> with no success</p>
  
  <p>
        
        
  </p>
  
  <p>Invoking generator com.google.gwt.uibinder.rebind.UiBinderGenerator
      [ERROR] No method found to apply message attribute customFormat Element  (:63)</p>
  
  <p>Is there a way to localize these elements?</p>