void PerformRefresh()
    {
        message       = "Refresh group...";
        ButtonEnabled = false;

        currentGroup.Refresh((KiiGroup group, Exception e) =>
        {
            ButtonEnabled = true;
            if (e != null)
            {
                message = "Failed to refresh group " + e.ToString();
                return;
            }
            currentGroup = group;
            message      = "Refresh group succeeded";
        });
    }