indentation on a RTC Page

I have a list page on which I use indentation.

NAV automatically provides the following options:

Expand - expands the selected line to the next level in the hierarchy

Collapse - collapses selected item to the previous level

Expand all - expands all items in the list to the lowest level

Collapse all - collapses the entire list to its highest summary level

My question - is there any function to control the expand / collapse behaviour through code? For example, I want to select a parent item, and expand its hierarchy to the lowest level, without expanding all the other items in the list.

Have a look at this Link

http://blogs.msdn.com/b/nav/archive/2010/10/20/some-tips-about-creating-quot-tree-view-quot-in-list-pages.aspx