This is an example of a program that draws tree-structured data, using a recursive traversal of the data structures. You have biological data that is hierarchical, and it shows how you can have disclosure triangles that show/hide subsets of the data.
If you click anywhere on the row, it will select that row. If you click on the triangle, it will toggle between show and hide of the child data. If there are no children, then you don't see the triangle.
Note that you have precise control over the indenting, line size, and every aspect of the styling without disturbing any other UI code.
