Binding Trees 
The example below shows the data binding of a Tree UI element to a context structure whose hierarchical structure is not known at design time and for which, therefore, a fixed number of levels cannot be determined at design time. The context provides a special node for this case, the recursive node.
Procedure
1. In the context of the view, create a node called TreeNode and set cardinality to 0..n and singleton to true.
2. Create a Recursion Node called RecursionNode.
3. In the Outline view, insert a Tree UI element into your view.
4. Insert a TreeNodeType into the Tree element.
5. Bind the Tree.dataSource property and the TreeNodeType.dataSource to the TreeNode.