passing variables from view to view

[eluser]kmunky[/eluser]
considering that i have:

views/page.php

Code:

$this->load->view("header");
$this->load->view($main_page);//variable passed from controller
$this->load->view("footer");

controllers/show.php

Code:

$this->load->view("page",$data);//$data contains the main_page title

and in my header view i have to pass a variable containing some categories(the site menu) to be listed. What is the correct way to accomplish this? thanks