public static T GetParent<T>(DependencyObject child) where T : DependencyObject        {            DependencyObject dependencyObject = VisualTreeHelper.GetParent(child);            if (dependencyObject != null)            {                T parent = dependencyObject as T;                if (parent != null)                {                    return parent;                }                else                {                    return GetParent <T>(dependencyObject);                }            }            else            {                return null;            }        }