title: Waiting for data for CellTable in GWT
body: <p>I'm using GWT 2.4 with <code>RequestFactory</code> mechanism. With bigger portions of <code>data</code> there is some extra time <code>(1-2 sec)</code> for <code>celltables</code> to get populated. During that time <code>celltable</code> is empty and user doesn't know if anything will appear in it. Is there any way to enable waiting <code>indicator</code> for <code>celltables</code> for the time they are being populated? </p>
  
  <p>I've already configured waiting indicator for <code>RequestFactory</code> calls, so I've got prepared <code>images</code> for it, but I don't know how to do it.</p>
  
  <p>Thanks.</p>