Assembly: PresentationFramework (in PresentationFramework.dll)
protected virtual void OnSelectedItemChanged( RoutedPropertyChangedEventArgs<Object> e )
The event data that the parameter e provides contains an DependencyPropertyChangedEventArgs.OldValue and a PropertyDataChangedEventArgs.NewValue. The DependencyPropertyChangedEventArgs.OldValue is set to the item that was previously selected, or is set to null if there is no previously selected item. Similarly, the PropertyDataChangedEventArgs.NewValue is set to the newly selected item, or is set to null if no new item is selected.