How can I determine if an nsIDOMWindow is the active window?

[Damien O'Brien]

Hi,
Using nsIWindowWatcher I'm able to get the active browser window. From that
I can get the child nsIDOMWindows that represent the Web page(s) (tab
windows) that are open in the browser. The problem I have is how do I
determine which of the web pages is the active page. So in other words how
can I determine which of the nsIDOMWindows represents the active window?
i.e. the top-most web page in the browser, the one someone using the browser
is reading.
I've included some sample code from how I'm doing this below. This code
works fine _EXCEPT_ that it's missing the bit to determine which of the web
page windows is the active window.
Thanks,
 Damien

void MyMozilla::TimerCallback(nsITimer *aTimer, void *aClosure) 
{
 OutputDebugString(_T("In the timer...\n"));  
 nsCOMPtr<nsIWindowWatcher> 
  wwatch(do_GetService(NS_WINDOWWATCHER_CONTRACTID)); 

 nsIDOMWindow *wind = NULL; 
 wwatch->GetActiveWindow(&wind); 

 if (wind) 
 { 
        PRUint32 nNumberOfWindows = 0;
        nsIDOMWindowCollection *windCollection = NULL;

        wind->GetFrames(&windCollection);
        windCollection->GetLength(&nNumberOfWindows);

        for (int nCnt=0;nCnt<nNumberOfWindows;nCnt++)
        {
                nsIDOMWindow *wind2 = NULL; 
                
                windCollection->Item(nCnt, &wind2);

                nsIDOMDocument *dom_doc = NULL;
                wind2->GetDocument(&dom_doc);

                if (dom_doc) 
                { 
                        nsCOMPtr<nsIDOMHTMLDocument>
                        htmlDomDocument(do_QueryInterface(dom_doc));

                        if (htmlDomDocument)
                        {
                                OutputDebugString(_T("Gotcha!!!...\n"));
                                nsEmbedString strTitleText;
                                htmlDomDocument->GetTitle (strTitleText);
                                const PRUnichar *strTitle =
strTitleText.get(); 
                                nsEmbedString strURLText;
                                htmlDomDocument->GetURL(strURLText);
                                const PRUnichar *strURL = strURLText.get();

                        }
                }
        }
 }
}

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