         var header:Button = Button(event.currentTarget);
         var oldIndex:int = selectedIndex;
         // content is placed onto the button so we have to access it via []
-        selectedChild = Container(IDataRenderer(header).data);
+        selectedChild = INavigatorContent(IDataRenderer(header).data);
         var newIndex:int = selectedIndex;
         if (oldIndex != newIndex)
             dispatchChangeEvent(oldIndex, newIndex, event);


        IDataRenderer(header).data = content;

        if (content is Container)
        {
            var contentContainer:Container = Container(content);

            header.label = contentContainer.label;
            if (contentContainer.icon)
                header.setStyle("icon", contentContainer.icon);

            // If the child has a toolTip, transfer it to the header.
            var toolTip:String = contentContainer.toolTip;
            if (toolTip && toolTip != "")
            {
                header.toolTip = toolTip;
                contentContainer.toolTip = null;
            }
        }


    /**
     *  @private
     */
    private function instantiateChild(child:INavigatorContent):void
    {
        // fix for bug#137430
        // when the selectedChild index is -1 (invalid value due to any reason)
