Data Pagination
===============
The process of pagination takes place when we need to present big groups of arbitrary data gradually. Phalcon\\Paginator offers a
fast and convenient way to split these sets of data browsable pages.

Data Adapters
-------------
This component makes use of adapters to encapsulate different sources of data:

+--------------+------------------------------------------------------------+
| Adapter      | Description                                                |
+==============+============================================================+
| NativeArray  | Use a PHP array as source data                             |
+--------------+------------------------------------------------------------+
| Model        | Use a Phalcon\\Mvc\\Model\\Resultset object as source data |
+--------------+------------------------------------------------------------+

Using Paginators
----------------
In the example below, the paginator will use as its source data the result of a query from a model, and limit the displayed data to 10 records per page:

.. code-block:: php

    <?php

    // Current page to show
    // In a controller this can be:
    // $this->request->getQuery('page', 'int'); // GET
    // $this->request->getPost('page', 'int'); // POST
    $currentPage = (int) $_GET["page"];

    // The data set to paginate
    $robots = Robots::find();

    // Create a Model paginator, show 10 rows by page starting from $currentPage
    $paginator = new \Phalcon\Paginator\Adapter\Model(
        array(
            "data" => $robots,
            "limit"=> 10,
            "page" => $currentPage
        )
    );

    // Get the paginated results
    $page = $paginator->getPaginate();

Variable $currentPage controls the page to be displayed. The $paginator->getPaginate() returns a $page
object that contains the paginated data. It can be used for generating the pagination:

.. code-block:: html+php

    <table>
        <tr>
            <th>Id</th>
            <th>Name</th>
            <th>Type</th>
        </tr>
        <?php foreach ($page->items as $item) { ?>
        <tr>
            <td><?php echo $item->id; ?></td>
            <td><?php echo $item->name; ?></td>
            <td><?php echo $item->type; ?></td>
        </tr>
        <?php } ?>
    </table>

The $page object also contains navigation data:

.. code-block:: html+php

    <a href="/robots/search">First</a>
    <a href="/robots/search?page=<?= $page->before; ?>">Previous</a>
    <a href="/robots/search?page=<?= $page->next; ?>">Next</a>
    <a href="/robots/search?page=<?= $page->last; ?>">Last</a>

    <?php echo "You are in page ", $page->current, " of ", $page->total_pages; ?>

Page Attributes
---------------
The $page object has the following attributes:

+---------+--------------------------------------------------------+
| Adapter | Description                                            |
+=========+========================================================+
| items   | The set of records to be displayed at the current page |
+---------+--------------------------------------------------------+
| before  | The previous page to the current one                   |
+---------+--------------------------------------------------------+
| next    | The next page to the current one                       |
+---------+--------------------------------------------------------+
| last    | The last page in the set of records                    |
+---------+--------------------------------------------------------+

Implementing your own adapters
------------------------------
The :doc:`Phalcon\\Paginator\\AdapterInterface <../api/Phalcon_Paginator_AdapterInterface>` interface must be implemented in order to create your own paginator adapters or extend the existing ones:

.. code-block:: php

    <?php

    class MyPaginator implements Phalcon\Paginator\AdapterInterface  {

        /**
         * Adapter constructor
         *
         * @param array $config
         */
        public function __construct($config);

        /**
         * Set the current page number
         *
         * @param int $page
         */
        public function setCurrentPage($page);

        /**
         * Returns a slice of the resultset to show in the pagination
         *
         * @return stdClass
         */
        public function getPaginate();

    }