private static void OnDisplayModeChanged(DependencyObject source, DependencyPropertyChangedEventArgs args)
        {
            BookDisplayMode mode = (BookDisplayMode)args.NewValue;
            KineBook        book = source as KineBook;

            if (mode == BookDisplayMode.Normal)
            {
                //book.translate.X = 0;
                //book.scale.ScaleX = 1;
                //book.scale.ScaleY = 1;
                book.translate.BeginAnimation(TranslateTransform.XProperty, null);
                book.scale.BeginAnimation(ScaleTransform.ScaleXProperty, null);
            }
            else
            {
                if (book.CurrentPage == BookCurrentPage.LeftSheet)
                {
                    book.AnimateToLeftSheet();
                }
                else
                {
                    book.AnimateToRightSheet();
                }
            }
        }
        private static void OnCurrentPageChanged(DependencyObject source, DependencyPropertyChangedEventArgs args)
        {
            BookCurrentPage currentPage = (BookCurrentPage)args.NewValue;
            KineBook        b           = source as KineBook;

            if (currentPage == BookCurrentPage.LeftSheet)
            {
                b.AnimateToRightSheet();
            }
            else
            {
                b.AnimateToLeftSheet();
            }
        }