Zend_Paginator can be told to cache the data it has already
passed on, preventing the adapter from fetching them each time they are used.
To tell paginator to automatically cache the adapter's data, just pass to
its setCache() method a Zend_Cache_Core
instance.
<?php
$paginator = Zend_Paginator::factory($someData);
$fO = array('lifetime' => 3600, 'automatic_serialization' => true);
$bO = array('cache_dir'=>'/tmp');
$cache = Zend_cache::factory('Core', 'File', $fO, $bO);
Zend_Paginator::setCache($cache);
As far as Zend_Paginator has got a
Zend_Cache_Core instance, data will be cached. Sometimes you
would like not to cache data even if you already passed a cache instance. You should
then use setCacheEnable() for that.
<?php
$paginator = Zend_Paginator::factory($someData);
// $cache is a Zend_Cache_Core instance
Zend_Paginator::setCache($cache);
// ... later on the script
$paginator->setCacheEnable(false);
// cache is now disabled
When a cache is set, data are automatically stored in it and pulled out from
it. It then can be useful to empty the cache manually. You can get this done by
calling clearPageItemCache($pageNumber).
If you don't pass any parameter, the whole cache will be empty. You can optionally
pass a parameter representing the page number to empty in the cache:
<?php
$paginator = Zend_Paginator::factory($someData);
Zend_Paginator::setCache($cache);
$items = $paginator->getCurrentItems();
// page 1 is now in cache
$page3Items = $paginator->getItemsByPage(3);
// page 3 is now in cache
// clear the cache of the results for page 3
$paginator->clearPageItemCache(3);
// clear all the cache data
$paginator->clearPageItemCache();
Changing the item count per page will empty the whole cache as it would have become invalid:
<?php
$paginator = Zend_Paginator::factory($someData);
Zend_Paginator::setCache($cache);
// fetch some items
$items = $paginator->getCurrentItems();
// all the cache data will be flushed:
$paginator->setItemCountPerPage(2);
It is also possible to see the data in cache and ask for them directly.
getPageItemCache() can be used for that:
<?php
$paginator = Zend_Paginator::factory($someData);
$paginator->setItemCountPerPage(3);
Zend_Paginator::setCache($cache);
// fetch some items
$items = $paginator->getCurrentItems();
$otherItems = $paginator->getItemsPerPage(4);
// see the cached items as a two-dimension array:
var_dump($paginator->getPageItemCache());