Help needed automating a menu action using WPF UI Automation

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C#

WPF

UI

automation

This is my FindMenu code from the UI Automation exercise I am working on:

private ExpandCollapsePattern FindMenu(VTServiceMenu menu)
{
    try
    {
        AutomationElement menuElement = _VTMainAutomationElement.FindFirst(TreeScope.Descendants, new PropertyCondition(AutomationElement.NameProperty, menu.ToString()));
        AutomationPattern[] autoPattern;
        autoPattern = menuElement.GetSupportedPatterns();
        ExpandCollapsePattern expPattern = menuElement.GetCurrentPattern(ExpandCollapsePattern.Pattern) as ExpandCollapsePattern;
        return expPattern;
    }
    catch (Exception e1)
    {

        LogEntry("Error " + e1.Message + " expanding menu in " + _VTMainAutomationElement.FindFirst(TreeScope.Descendants, new PropertyCondition(AutomationElement.NameProperty, menu.ToString())));
        throw new InvalidOperationException("Error " + e1.Message + " expanding menu in " + _VTMainAutomationElement.FindFirst(TreeScope.Descendants, new PropertyCondition(AutomationElement.NameProperty, menu.ToString())));
        return null;
    }
}

Break after : autoPattern = menuElement.GetSupportedPatterns();

Examine: autoPattern[0].ProgrammaticName. Actual Value is "InvokePatternIdentifiers.Pattern" string, expected value is "ExpandCollapsePatternIdentifiers.Pattern" string
Exception on : ExpandCollapsePattern

This is the corresponding code from Kaila's Calculator example here on CodeProject:

private ExpandCollapsePattern FindMenu(CalculatorMenu menu)
{
    AutomationElement menuElement = _calculatorAutomationElement.FindFirst(TreeScope.Descendants, new PropertyCondition(AutomationElement.NameProperty, menu.ToString()));
    AutomationPattern[] autoPattern;
    autoPattern = menuElement.GetSupportedPatterns();
    ExpandCollapsePattern expPattern = menuElement.GetCurrentPattern(ExpandCollapsePattern.Pattern) as ExpandCollapsePattern;
    return expPattern;
}

It has the expected "ExpandCollapsePatternIdentifiers.Pattern" in autoPattern[0].ProgrammaticName. I have compared how he sets up _calculatorAutomationElement against my _VTMainAutomationElement, and his CalculatorMenu against my VTServiceMenu. If there are differences, then I have missed them.

I have done nothing with XAML - is that my missing link?