Admin Page Grid issue

Question

I've created my Admin Page Grid but there is a strange issue when I try to prepare the collection. This is the code:

  protected function _prepareCollection()
  {
      $collection = Mage::getModel('catalog/product')->getCollection()
        ->addAttributeToSelect('*')
        ->addFieldToFilter('visibility', Mage_Catalog_Model_Product_Visibility::VISIBILITY_BOTH)
        ->addAttributeToSort('entity_id', 'desc');
      $collection->getSelect()->limit(5,1);
      $this->setCollection($collection);
      return parent::_prepareCollection();
  }

and this the result:

I've try to limit the result to 5 items but it is ignored. The system gets 740 items. The query generated seems to be right:

SELECT `e`.*, `at_visibility`.`value` AS `visibility` FROM `catalog_product_entity` AS `e` INNER JOIN `catalog_product_entity_int` AS `at_visibility` ON (`at_visibility`.`entity_id` = `e`.`entity_id`) AND (`at_visibility`.`attribute_id` = '102') AND (`at_visibility`.`store_id` = 0) WHERE (at_visibility.value = '4') ORDER BY `e`.`entity_id` desc LIMIT 5 OFFSET 1

I've covered the if the method return $this instead of parent::_prepareCollection(), I obtain the right items but in the Pager area I continue to see "Total 740 records found".

Where am I wrong?

Answer 1

You can modify a function called _preparePage in your grid class.

e.g.

protected function _preparePage()
{
    $this->getCollection()->setPageSize(5);
    $this->getCollection()->setCurPage(1);
}

Note: Its not a complete solution, just an example to show the usage.

Also you have to edit the app/design/adminhtml/default/default/template/widget/grid.phtml file to include the new page size in the grid pagination toolbar. (See this)

Answer 2

I'm not sure, but I think it's impossible to apply limit method to collection. I assume that magento add it's own limitation "view N items per page"