How do I subclass one of my own controllers? [SOLVED]

[eluser]CoderReborn[/eluser]
I have a controller named "Done" which extend the Controller class.

I am trying to create a subclass controller called "ToDo" with the following code:

Code:

<?php

class Todo extends Done
{

    public function __construct()
    {
        parent::__construct();
        echo "Todo constructor<br/>";
    }

    public function index()
    {
        echo "Inside Todo index <br/>";
    }

}

?&gt;

However, this causes a blank screen.
When I change "Done" to "Controller" (not what I want), the display is correct.

How do I subclass one of my own controllers?

Thanks!