//public static void SetContent(Object content)
        //{
        //    if (content != null)
        //    {
        //        ContentFrame.SetContent(content);
        //    }
        //}

        public static void Navigate(FantasyFrame frame, String uri, Object parameter = null)
        {
            if (frame != null && !String.IsNullOrEmpty(uri))
            {
                frame.NavigatingParameter = parameter;
                frame.Source = new Uri(uri, UriKind.RelativeOrAbsolute);
            }
        }
 private void RegisterChildFrame(FantasyFrame frame)
 {
     // do not register existing frame
     if (!GetChildFrames().Contains(frame))
     {
         var r = new WeakReference<FantasyFrame>(frame);
         this.ChildFrames.Add(r);
     }
 }