Сброс / установка параметров пагинации (pagination) при переходе или обновлении страницы - Разработка расширений для Joomla 3.x

    protected function getListQuery()
    {
        $query = $this->getDbo()->getQuery( true );
        $query->select(array('a.name', 'a.id'));
		$query->from('#__myworks AS a');

		// Join over the categories.
		$query->select('c.title AS category_title')
			->join('LEFT', '#__categories AS c ON c.id = a.catid');

		if(isset($_GET["catid"]))
		{
			if($_GET["catid"] != "all")
			{
				$query->where('catid = '.$_GET["catid"]);	
			}
		}
        return $query;
    }

jimport('joomla.application.component.view');

class MyworksViewMyworks extends JViewLegacy
{
    protected $mycategory;
    protected $pagination;
    protected $items;

    public function display($tpl = null)
    {
        $this->mycategory = $this->get('Mycategories');	
        $this->items = $this->get( 'Items' );
        $this->pagination = $this->get( 'Pagination' );

        $this->setLayout('default_ajax');

        parent::display($tpl);
    }
}

<?php foreach($this->mycategory as $i => $mycategory) : ?>
<a href="<? echo JRoute::_('index.php'.'?catid='.$category->id);?>"><?=$mycategory->title;?></a>
<?php endforeach; ?>   

<? if($this->pagination->total > 0): ?>
  <div class="block-gallery-items-img-load"><?php echo $this->loadTemplate('ajax'); ?></div>
<? endif ?>

<?php foreach($this->items as $i => $items) : ?>
<div><?=$items->title;?></div>
<?php endforeach; ?> 

<div id="next_button_items" rel="<?php echo JRoute::_('&limit='.$this->pagination->limit+20); ?>">[ загрузить ещё 20 ]</div>

$(document).on('click', '#next_button_items', function () {
	$.get($(this).attr('rel') + '&format=raw', function (responce) {
		$('.block-gallery-items-img-load').html(responce);
	});
	return false;
});

$this->setState('list.start', 'значение');
$this->setState('list.limit', 'значение');

// Join over the categories.

if(isset($_GET["catid"]))

$query->where('catid = '.$_GET["catid"]);

$query->where('catid = '.(int)$_GET["catid"]);

public function populateState($ordering = null, $direction = null)
{
     $app = JFactory::getApplication();
     parent::populateState($ordering, $direction);
     $cur_cat = (int) $_GET["catid"];
     $old_cat = $app->getUserState($this->context. '.category');
     if ($old_cat != $cur_cat) {
         $app->setUserState($this->context . '.category', $cur_cat);
         $this->setState('list.start', 0);
         $this->setState('list.limit', 20);
     }
}

$app->setUserState('global.list.limit', 20);
$app->setUserState($this->context . '.limitstart', 0); 

if( !isset($_GET["limit"]) )
}
	$cur_id = JSite::getMenu()->getActive()->id;
	$old_id = $app->getUserState($this->context.'.id');
	if ($old_id != $cur_id) {
		$app->setUserState($this->context.'.id', $cur_id);
		$this->setState('list.start', 0);
		$this->setState('list.limit', 20);
		$app->setUserState('global.list.limit', 20);
		$app->setUserState($this->context . '.limitstart', 0); 
	}
}

if( isset($_GET["limit"])==0 )

if( !isset($_GET["limit"]) )

if (!isset($cur_cat)) 
{
   $cur_cat = 'all';  
}	

$input = JFactory::getApplication->input;
$cur_cat = $input->getInt('catid' , 0);

if(!isset($_GET["format"]))
{
	$cur_path = $_SERVER['REQUEST_URI'];
	$old_path = $app->getUserState($this->context.'.path');
	if ($old_path != $cur_path) {
		$app->setUserState($this->context.'.path', $cur_path);
		$this->setState('list.start', 0);
		$this->setState('list.limit', 20);
		//$app->setUserState('global.list.limit', 20);
		//$app->setUserState($this->context . '.limitstart', 0); 
	}
}