///--------------------------------------------------------------------
/// <summary>
/// Finds all automation elements that satisfy 
/// the specified condition(s).
/// </summary>
/// <param name="rootElement">
/// The automation element from which to start searching.
/// </param>
/// <returns>
/// A collection of automation elements satisfying 
/// the specified condition(s).
/// </returns>
///--------------------------------------------------------------------
private AutomationElementCollection FindAutomationElement(
    AutomationElement rootElement)
{
    if (rootElement == null)
    {
        throw new ArgumentException("Root element cannot be null.");
    }

    PropertyCondition conditionOn =
        new PropertyCondition(
        TogglePattern.ToggleStateProperty, ToggleState.On);

    PropertyCondition conditionIndeterminate =
        new PropertyCondition(
        TogglePattern.ToggleStateProperty, ToggleState.Indeterminate);

    // Use any combination of the preceding condtions to 
    // find the control(s) of interest
    OrCondition condition = new OrCondition(
        conditionOn,
        conditionIndeterminate);

    return rootElement.FindAll(TreeScope.Descendants, condition);
}