private void SetParentCell ()
{
Relation [] relations = accessible.RelationSet;
foreach (Relation relation in relations) {
if (relation.Type == RelationType.NodeChildOf) {
parentCell = Element.GetElement (relation.Targets [0]) as TreeItemElement;
break;
}
}
ancestors = new List<TreeItemElement> ();
for (TreeItemElement ancestor = parentCell; ancestor != null; ancestor = ancestor.parentCell)
ancestors.Add (ancestor);
}