title: Flex mx:DataGrid row index
body: <p>Is it possible to dynamically show row index for <code>DataGrid</code> rows ?
  I have a static <code>ArrayCollection</code> which is set to be <code>DataGrid</code>'s data provider and I would like to always have row numbering for each populated row (e.g. in a column called "#").</p>
  
  <p>Thanks!</p>