////<summary>
        /// Cancel synchronized input processing.
        ///</summary>
        void ISynchronizedInputProvider.Cancel()
        {
            UIElement e = _owner as UIElement;

            if (e != null)
            {
                e.CancelSynchronizedInput();
            }
            else
            {
                ContentElement ce = _owner as ContentElement;
                if (ce != null)
                {
                    ce.CancelSynchronizedInput();
                }
                else
                {
                    UIElement3D e3D = (UIElement3D)_owner;
                    e3D.CancelSynchronizedInput();
                }
            }
        }