title: issue with WPF combobox selectionchanged event
body: <p>I have my logic of opening a search modal window based on user selection in a combobox. What happens is the modal window opens but the selected item is not reflected in the combobox. i.e Unlike a Windows form, the WPF combobox is not reflecting the newly selected item when the selectionchanged event is fired. </p>
  
  <p>well i would have used the SelectionChangeCommitted in a Winform, i am not finding an equivalent in this case. Am i missing something thats obvious? Thanks! </p>