MY_Controller:

<?php

class  MY_Controller  extends CI_Controller  {

var $data;

    function __construct()
	{
		parent::__construct();

		$this->load->model('navigation_model');

		$this->data['navigation_bar'] = $this->navigation_model->getMainNav();



			if ($this->session->userdata('is_logged_in'))
	        {
	            $this->data['user_panel'] = 'user_panel_view';
	        } else {
				$this->data['user_panel'] = 'login_form';
			}
	}
}
?>

Welcome Controller:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Welcome extends MY_Controller {

	function __construct()
	{
		parent::__construct();
	}

	function index()
	{
		$this->data['title'] = "Maharishi Unniversity of Management: Chess Club";
		$this->data['main_content'] = 'welcome_view';
		$this->load->view('includes/template_view', $this->data);
	}

}
?>