public ObservableCollection <ITreeNode> BuildRegularNodesFrom( string promptName , string parameterName , IEnumerable <ValidValue> availableItems , ITreeNode parentNode, bool hasChildLevel) { var treeNodes = new List <ITreeNode>(); foreach (var item in availableItems) { var treeNode = _treeNodeBuilder.BuildRegularNodeFrom( promptName , parameterName , item , parentNode , hasChildLevel); treeNodes.Add(treeNode); } return(new ObservableCollection <ITreeNode>(treeNodes)); }