private static void OnCollapseModePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            CollapsableGridSplitter s = d as CollapsableGridSplitter;

            GridSplitterCollapseMode value = (GridSplitterCollapseMode)e.NewValue;

            s.OnCollapseModeChanged(value);
        }
        private static void OnIsCollapsedPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            CollapsableGridSplitter s = d as CollapsableGridSplitter;

            bool value = (bool)e.NewValue;

            s.OnIsCollapsedChanged(value);
        }