GridController.php

<?php

/*
 * This file is part of the Assetic package.
 *
 * (c) Kris Wallsmith <kris.wallsmith@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Kris\GridBundle\Controller;

use Kris\GridBundle\Grid\GridInterface;
use Symfony\Component\Form\Form;
use Symfony\Component\HttpFoundation\Request;

/**
 * An abstract controller for grid views.
 *
 * @author Kris Wallsmith <kris.wallsmith@symfony-project.com>
 */
abstract class GridController
{
    protected $request;
    protected $session;
    protected $grid;

    public function __construct(Request $request, GridInterface $grid)
    {
        $this->request = $request;
        $this->session = $request->getSession();
        $this->grid = $grid;
    }

    abstract protected function getSessionKey();

    protected function handle()
    {
        $form = $this->grid->createForm('filter');

        if ($this->request->query->has('reset')) {
            $this->session->remove($this->getSessionKey());
        }

        if (is_array($data = $this->request->query->get('filter'))) {
            // begin
            $snapshot = clone $this->grid;
            $this->bindForm($form, $data);

            if ($form->isValid()) {
                // commit
                $this->session->set($this->getSessionKey(), $form->getDisplayedData());
            } else {
                // rollback
                $this->grid = $snapshot;
            }
        } else {
            $this->bindForm($form);
        }

        $this->grid->load();
    }

    private function bindForm(Form $form, $data = array())
    {
        $form->submit(array_merge(
            $form->getDisplayedData(),
            $this->session->get($this->getSessionKey(), array()),
            $data
        ));

        $form->validate();
    }
}

GridInterface.php

<?php

/*
 * This file is part of the Assetic package.
 *
 * (c) Kris Wallsmith <kris.wallsmith@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Kris\GridBundle\Grid;;

use Symfony\Component\Validator\ValidatorInterface;

/**
 * An admin grid.
 *
 * Implementation of the Countable interface should return the total number
 * of items that are present when the looping through the iterator. If the
 * iterator is a MongoCursor, this means passing true to its count() method.
 */
interface GridInterface extends \IteratorAggregate, \Countable
{
    /**
     * Creates a new filter form for the current grid.
     *
     * @param string $key The form key
     *
     * @return Symfony\Component\Form\Form The default filter form
     */
    function createForm($key);

    /**
     * Loads the current grid with data.
     *
     * This method should use the data bound to the grid using the form to
     * craft a database query. Those data are then accessible via the iterator
     * interface.
     */
    function load();
}

LICENSE

Copyright (c) Kris Wallsmith

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is furnished
to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.