title: How can I be notified if a DataGrid column is sorted (and not sorting)
body: <p>I need to have kind of an <code>Sorted</code> event for a <a href="http://msdn.microsoft.com/de-de/library/cc189753.aspx" rel="noreferrer"><code>DataGrid</code></a> in a WPF application but cannot find a way to get it.</p>
  
  <p>Here is what I tried:</p>
  
  <p>The <code>DataGrid</code> provides an event <a href="http://msdn.microsoft.com/de-de/library/system.windows.controls.datagrid.sorting.aspx" rel="noreferrer"><code>Sorting</code></a>, but I cannot use it as it is fired before the sorting is done. The <code>EventArgs</code> give me the column which is sorted but not the way it is sorted and if I get the sort direction it is set to the old value. Of course I could guess what it will be as I know that it flips from none to ascending and finally to descending but that would be no solution as it would fail if the behavior of the control changes.</p>
  
  <p>Second try:</p>
  
  <p>The <code>DataGrid</code> has a default view which provides access to a <a href="http://msdn.microsoft.com/de-de/library/ms644332.aspx" rel="noreferrer"><code>SortDescriptionCollection</code></a>. This collection holds all sorting properties but I don't see any possibility to let me inform about changes.</p>
  
  <p>I have to say that I'm looking for a solution as clean as possible as it will be used in a large project on which I can't use solutions which could fail if the environment changes.</p>
  
  <p>Does anyone know from experience (or documentation?) how I could solve this problem?</p>
  
  <p><strong>Edit:</strong> To make more clear what I want to achieve: I need to get informed which <code>DataGrid</code> column is sorted in which direction when a user sort a column. It is not necessary that this information comes after the sorting itself, it just has to be correct ;)</p>