private void OnPositionAdded(object sender, ModelAddedEventArgs<Position_AccessRule> e)
 {
     var positionAccessRuleVm = new PositionAccessRuleVM(e.NewModel, Access, RelationDirection.Reverse);
     SelectedItems.AddNewItem(positionAccessRuleVm);
     SelectedItems.CommitNew();
 }
        private void OnAccessRuleChanged(object sender, ModelAddedEventArgs<Position_AccessRule> e)
        {
            var positionAccessRule = new PositionAccessRuleVM(e.NewModel, Access, RelationDirection.Straight);
            var newNode = FindNode(RootNode, positionAccessRule.AccessRuleId) as PositionAccessNodeVM;
            if (newNode != null)
                newNode.PositionAccess = positionAccessRule.Type;

            if (CurrentNode == RootNode)
            {
                CurrentNode = newNode;
            }
        }