private void OnResizeBothDelta(object sender, DragDeltaEventArgs e)
{
if (double.IsNaN(scrollViewer.Height)) scrollViewer.Height = scrollViewer.ActualHeight;
scrollViewer.Height = Math.Min(Math.Max(galleryPanel.GetItemSize().Height, scrollViewer.Height + e.VerticalChange), MaxDropDownHeight);
menuPanel.Width = Double.NaN;
if (Double.IsNaN(galleryPanel.Width)) galleryPanel.Width = galleryPanel.ActualWidth;
galleryPanel.Width = Math.Max(galleryPanel.Width + e.HorizontalChange, minimalGallerylWidth);
}