CodeIgniter is easy to understand if you know how MVC design pattern works. Just need to define your model, your controller and your views.

However, sometimes you need to reuse code in all your site pages and probably you ask yourself “How do I do that?”.

Well, here is a simple tip that may help you to reuse generic data, fields, etc. in your CodeIgniter application.

First, I usually define my own MY_Controller class as a super class of the default Controller. You just need to create your MY_Controller.php file under application/libraries.

Then, I put there a simple $data array as a class property that will hold the data that I need to display in all my site pages.

For example, I may be interested in keeping the following variables:

$this->data['themeurl'] = $this->theme_url;
$this->data['hostname'] = $_SERVER['SERVER_NAME'];
$this->data['is_admin'] = $this->is_admin();
$this->data['is_logged_in'] = $this->dx_auth->is_logged_in();

Later, when I need to create the controller method for a given functionality, I do the following:

Imagine we are creating a Bulletin board for a web site. So I created a bulletin controller class that will handle the CRUD operations. As I mentioned before, I will make that class to extend MY_Controller. Next, in the CRUD methods, I use the following code:

function index()
{
	$messages = $this->bulletin_model->get_messages();
        $this->data['list'] = $messages;
	$this->load->view('bulletin_list', $this->data );
}

Notice the $this->data parameter when calling $this->load->view(), instead of using $data. By doing this, I can use that multipurpose data array that was introduced in the super controller class, and loaded with default values.