var async_mg = {
  onLoad: function() {
    // initialization code

    new aSyncMtpAltListener();

    this.initialized = true;
  }
};



function aSyncMtpAltListener()
{
	window.QueryInterface(Components.interfaces.nsIInterfaceRequestor)
		      .getInterface(Components.interfaces.nsIWebNavigation)
		      	.QueryInterface(Components.interfaces.nsIDocShell)
		      	.QueryInterface(Components.interfaces.nsIInterfaceRequestor)
					.getInterface(Components.interfaces.nsIURIContentListener)
					.parentContentListener = this;
}


aSyncMtpAltListener.prototype =
{
   QueryInterface: function(iid)
    {
        if (iid.equals(Components.interfaces.nsIURIContentListener) ||
         iid.equals(Components.interfaces.nsISupportsWeakReference) ||
            iid.equals(Components.interfaces.nsISupports))
            return this;
        throw Components.results.NS_NOINTERFACE;
    },
    onStartURIOpen: function(aUri)
    {	// We'll just sit back and wait...
           return false;
    },
    doContent: function(aContentType, aIsContentPreferred, aRequest, aContentHandler )
    {	alert('Argh! At last! This is: ' + aContentType);
      //var oChannel = aRequest.QueryInterface(Ci.nsIChannel);
      //alert(oChannel.contentType);
			throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
    },
    canHandleContent: function(aContentType, aIsContentPreferred, aDesiredContentType)
   {
      alert(aContentType);
   		return aContentType == 'multipart/alternate';
      throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
    },
    isPreferred: function(aContentType, aDesiredContentType)
   {	alert(aContentType);
   		return aContentType == 'multipart/alternate';
   		try
       {
            var webNavInfo =
            Components.classes["@mozilla.org/webnavigation-info;1"]
                        .getService(Components.interfaces.nsIWebNavigationInfo);
            return webNavInfo.isTypeSupported(aContentType, null);
        }
      catch (e)
      {
            return false;
        }
    },
      GetWeakReference : function()
   {
       throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
    }
};



window.addEventListener("load", function(e) { async_mg.onLoad(e); }, false);