/// <summary>
/// Gets the ScrollViewer that contains the containers of an
/// ItemsControl.
/// </summary>
/// <param name="control">The ItemsControl.</param>
/// <returns>
/// The ScrollViewer that contains the containers of an ItemsControl, or
/// null if a ScrollViewer could not be found.
/// </returns>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="control" /> is null.
/// </exception>
public static ScrollViewer GetScrollHost(this ItemsControl control)
{
if (control == null)
{
throw new ArgumentNullException("control");
}
Panel itemsHost = GetItemsHost(control);
if (itemsHost == null)
{
return(null);
}
// Walk up the visual tree from the ItemsHost to the
// ItemsControl looking for a ScrollViewer that wraps
// the ItemsHost.
return(itemsHost
.GetVisualAncestors()
.Where(c => c != control)
.OfType <ScrollViewer>()
.FirstOrDefault());
}
