How does the pagination class work?

How does the pagination class work? - Printable Version

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+--- Thread: How does the pagination class work? (/showthread.php?tid=44101)

How does the pagination class work? - El Forum - 08-03-2011

[eluser]zxcv[/eluser]
Hello!
I'm wondering how the pagination class works.
My code is similiar to this:

CONTROLLER

Code:
class Books extends Controller {

  function __construct() {

    parent::Controller();

    $this->load->helper('url');

    $this->load->database();

  }

  function index() {

    // load pagination class

    $this->load->library('pagination');

    $config['base_url'] = base_url().'index.php/books/index/';

    $config['total_rows'] = $this->db->count_all('christian_books');

    $config['per_page'] = '5';

    $config['full_tag_open'] = '<p>';

    $config['full_tag_close'] = '</p>';

    $this->pagination->initialize($config);

    //load the model and get results

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

    $data['results'] = $this->books_model->get_books($config['per_page'],$this->uri->segment(3));

    // load the HTML Table Class

    $this->load->library('table');

    $this->table->set_heading('ID', 'Title', 'Author', 'Description');

    // load the view

    $this->load->view('books_view', $data);

  }

}

MODEL

Code:
class books_model extends Model {

  function __construct(){

    parent::Model();

  }

  function get_books($num, $offset) {

    $query = $this->db->get('christian_books', $num, $offset);    

    return $query;

  }

}

The view just makes the table and the pagination links.

I am wondering how "the flow of the pagination" is going here? Does a click on an pagination link call a new mysql query?

How does the pagination class work? - El Forum - 08-03-2011

[eluser]appleboy[/eluser]
Hi,

Please paste your books_view views source code.

How does the pagination class work? - El Forum - 08-03-2011

[eluser]waynhall[/eluser]
It sends a value (the offset) to the function at the url specified in config. (Which is the same as uri segment 3)
controller/function/$offset

You can access its value by placing a parameter on your index() function:

Code:
function index($offset) {

In your case, as you click next, you'll go to:
/books/index/5 // $this->index(5)
/books/index/10 // $this->index(10)
/books/index/15 // $this->index(15)
... and so on.

Its zero based, so going to the url books/ is the same as
/books/index/0

I usually create a separate function (not index) that handles the pagination:

Code:
public function index()

    {

            $this->page();

    }

    public function page($page = 0, $type = '') {

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

        $count = $this->news_posts->get_count($type);

        $per_page = 3;

        if($type == 'recipe') {

            $per_page = 10;

        }

        $title = 'News';

        $this->load->library('pagination');

        $config = array(

// blah blah blah