private void OnCollapsable(object sender, EventArgs e)
{
if ((_ribbonGroup != null) &&
(_ribbonGroup.Ribbon != null) &&
_ribbonGroup.RibbonTab.Groups.Contains(_ribbonGroup))
{
_changeService.OnComponentChanged(_ribbonGroup, null, _ribbonGroup.AllowCollapsed, !_ribbonGroup.AllowCollapsed);
_ribbonGroup.AllowCollapsed = !_ribbonGroup.AllowCollapsed;
}
}