I'm basically trying a session control. If the user is logged in, it's ok to move on. But if he's not logged in, then it will show a log-in screen and then die. However, when I use die or exit in the constructor, it does not show the log-in screen; it immediately dies. The code is as following:

private $username = null;
private $mongoid = null;
private $neoid = null;

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

    // session to global
    $this->username = $this->session->userdata( 'username');
    $this->mongoid = $this->session->userdata( 'mongoid');
    $this->neoid = $this->session->userdata( 'neoid');

    // check if user is logged in
    if( $this->username == "" || empty( $this->username)){
        $this->load->view( 'access/login');
        die;
    }
}

It shows the log-in page if die is not written there, but with die, it does not show. Why do I want to use die? Because if I don't use, it moves on the index function and I don't want it to execute index function if the user is not logged in.

What is wrong here? What should I use to stop executing?