///--------------------------------------------------------------------
/// <summary>
/// Subscribe to the selection item events of interest.
/// </summary>
/// <param name="selectionItem">
/// Automation element that supports SelectionItemPattern and is 
/// a child of a selection container that supports SelectionPattern
/// </param>
/// <remarks>
/// The events are raised by the SelectionItem elements, 
/// not the Selection container.
/// </remarks>
///--------------------------------------------------------------------
private void SetSelectionEventHandlers
    (AutomationElement selectionItem)
{
    AutomationEventHandler selectionHandler =
        new AutomationEventHandler(SelectionHandler);

    Automation.AddAutomationEventHandler(
        SelectionItemPattern.ElementSelectedEvent,
        selectionItem,
        TreeScope.Element,
        SelectionHandler);
    Automation.AddAutomationEventHandler(
        SelectionItemPattern.ElementAddedToSelectionEvent,
        selectionItem,
        TreeScope.Element,
        SelectionHandler);
    Automation.AddAutomationEventHandler(
        SelectionItemPattern.ElementRemovedFromSelectionEvent,
        selectionItem,
        TreeScope.Element,
        SelectionHandler);
}

private void SelectionHandler(object src, AutomationEventArgs e)
{
    // TODO: event handling
}