title: Extjs 4 Grid findcolumn
body: <p>I search a way in extjs 4 to find grid columns dynamic, because i wrote a function to show errors in editor grid. In version 3 i've made it over </p>
  
  <p><code>getColumnModel().findColumnIndex(cellname);</code> </p>
  
  <p>but column model no longer exists, does anybody has an idea?</p>
  
  <p>Regards</p>