This is a Codeigniter library for populating a tree/list of items based on the parent child relationships within a table. It can provide a tree view with unlimited levels of hierarchy and/or a full path to a given item.
Download and drag the Parentchild.php file into your application/libraries folder.
You will then need to load the library in any controller you want to use it in.
In the package you will find demo/usage code in the controllers and views folders. There is also a test database sql file included. Setup a database and configure CodeIgniter to use the database. Run the sql file to add the tables.
Copy the welcome controller and the views to your CodeIgniter installation.
A demo of the test is located here http://www.qcexample.com/ci_parentchild/
The demo code isn't the most beautiful thing you'll ever see but it will show you how to use the library for some basics.