category wise listing in CodeIgniter

[eluser]Unknown[/eluser]
I want a category wise listing in CodeIgniter framework. Output will be like below format. It will be totally dynamic. Values (colors/red/blue/green etc) can be added/updated from back-end. Can anybody provide me the relevant codes for this?
<ul id="mylist">
<li>colors
<ul>
<li>red</li>
<li>blue</li>
<li>green</li>
</ul>
</li>
<li>shapes
<ul>
<li>round</li>
<li>suare</li>
<li>circles</li>
</ul>
</li>