private static void SelectedItemPropertyChangedCallback(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs dependencyPropertyChangedEventArgs)
{
var instance = dependencyObject as ListPicker;
if (instance != null)
{
var newObject = dependencyPropertyChangedEventArgs.NewValue ?? instance.NullItem;
var selectableItem = newObject as ISelectable;
if (selectableItem != null)
selectableItem.IsSelected = false;
instance.ContentControlSelectedItem.Content = newObject;
}
}