pager.inc
Same filename in other branches
Functions to aid in presenting database results as a set of pages.
File
-
core/
includes/ pager.inc
View source
<?php
/**
* @file
* Functions to aid in presenting database results as a set of pages.
*/
use Drupal\Core\Template\Attribute;
use Drupal\Core\Url;
use Drupal\Component\Utility\Html;
/**
* Returns the current page being requested for display within a pager.
*
* @param int $element
* (optional) An integer to distinguish between multiple pagers on one page.
*
* @return int
* The number of the current requested page, within the pager represented by
* $element. This is determined from the URL query parameter
* \Drupal::request()->query->get('page'), or 0 by default. Note that this
* number may differ from the actual page being displayed. For example, if a
* search for "example text" brings up three pages of results, but a user
* visits search/node/example+text?page=10, this function will return 10,
* even though the default pager implementation adjusts for this and still
* displays the third page of search results at that URL.
*
* @deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use
* \Drupal\Core\Pager\PagerParametersInterface->findPage() instead.
*
* @see https://www.drupal.org/node/2779457
* @see \Drupal\Core\Pager\PagerParametersInterface::findPage()
*/
function pager_find_page($element = 0) {
@trigger_error(__FUNCTION__ . ' is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use \\Drupal\\Core\\Pager\\PagerParametersInterface->findPage() instead. See https://www.drupal.org/node/2779457', E_USER_DEPRECATED);
/* @var $pager_parameters \Drupal\Core\Pager\PagerParametersInterface */
$pager_parameters = \Drupal::service('pager.parameters');
return $pager_parameters->findPage($element);
}
/**
* Initializes a pager.
*
* This function sets up the necessary global variables so that the render
* system will correctly process #type 'pager' render arrays to output pagers
* that correspond to the items being displayed.
*
* If the items being displayed result from a database query performed using
* Drupal's database API, and if you have control over the construction of the
* database query, you do not need to call this function directly; instead, you
* can simply extend the query object with the 'PagerSelectExtender' extender
* before executing it. For example:
* @code
* $query = \Drupal::database()->select('some_table')
* ->extend('Drupal\Core\Database\Query\PagerSelectExtender');
* @endcode
*
* However, if you are using a different method for generating the items to be
* paged through, then you should call this function in preparation.
*
* The following example shows how this function can be used in a controller
* that invokes an external datastore with an SQL-like syntax:
* @code
* // First find the total number of items and initialize the pager.
* $where = "status = 1";
* $total = mymodule_select("SELECT COUNT(*) FROM data " . $where)->result();
* $num_per_page = \Drupal::config('mymodule.settings')->get('num_per_page');
* $page = pager_default_initialize($total, $num_per_page);
*
* // Next, retrieve the items for the current page and put them into a
* // render array.
* $offset = $num_per_page * $page;
* $result = mymodule_select("SELECT * FROM data " . $where . " LIMIT %d, %d", $offset, $num_per_page)->fetchAll();
* $render = [];
* $render[] = [
* '#theme' => 'mymodule_results',
* '#result' => $result,
* ];
*
* // Finally, add the pager to the render array, and return.
* $render[] = ['#type' => 'pager'];
* return $render;
* @endcode
*
* A second example involves a controller that invokes an external search
* service where the total number of matching results is provided as part of
* the returned set (so that we do not need a separate query in order to obtain
* this information). Here, we call pager_find_page() to calculate the desired
* offset before the search is invoked:
* @code
* // Perform the query, using the requested offset from pager_find_page().
* // This comes from a URL parameter, so here we are assuming that the URL
* // parameter corresponds to an actual page of results that will exist
* // within the set.
* $page = pager_find_page();
* $num_per_page = \Drupal::config('mymodule.settings')->get('num_per_page');
* $offset = $num_per_page * $page;
* $result = mymodule_remote_search($keywords, $offset, $num_per_page);
*
* // Now that we have the total number of results, initialize the pager.
* pager_default_initialize($result->total, $num_per_page);
*
* // Create a render array with the search results.
* $render = [];
* $render[] = [
* '#theme' => 'search_results',
* '#results' => $result->data,
* '#type' => 'remote',
* ];
*
* // Finally, add the pager to the render array, and return.
* $render[] = ['#type' => 'pager'];
* return $render;
* @endcode
*
* @param int $total
* The total number of items to be paged.
* @param int $limit
* The number of items the calling code will display per page.
* @param int $element
* (optional) An integer to distinguish between multiple pagers on one page.
*
* @return int
* The number of the current page, within the pager represented by $element.
* This is determined from the URL query parameter
* \Drupal::request()->query->get('page), or 0 by default. However, if a page
* that does not correspond to the actual range of the result set was
* requested, this function will return the closest page actually within the
* result set.
*
* @deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use
* \Drupal\Core\Pager\PagerManagerInterface->defaultInitialize() instead.
*
* @see https://www.drupal.org/node/2779457
* @see \Drupal\Core\Pager\PagerManagerInterface::createPager()
*/
function pager_default_initialize($total, $limit, $element = 0) {
@trigger_error(__FUNCTION__ . ' is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use \\Drupal\\Core\\Pager\\PagerManagerInterface->createPager() instead. See https://www.drupal.org/node/2779457', E_USER_DEPRECATED);
/* @var $pager_manager \Drupal\Core\Pager\PagerManagerInterface */
$pager_manager = \Drupal::service('pager.manager');
$pager = $pager_manager->createPager($total, $limit, $element);
return $pager->getCurrentPage();
}
/**
* Compose a URL query parameter array for pager links.
*
* @return array
* A URL query parameter array that consists of all components of the current
* page request except for those pertaining to paging.
*
* @deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use
* \Drupal\Core\Pager\PagerParametersInterface->getQueryParameters() instead.
*
* @see https://www.drupal.org/node/2779457
* @see \Drupal\Core\Pager\PagerParametersInterface::getQueryParameters()
*/
function pager_get_query_parameters() {
@trigger_error(__FUNCTION__ . ' is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use \\Drupal\\Core\\Pager\\PagerParametersInterface->getQueryParameters() instead. See https://www.drupal.org/node/2779457', E_USER_DEPRECATED);
/* @var $pager_params \Drupal\Core\Pager\PagerParametersInterface */
$pager_params = \Drupal::service('pager.parameters');
return $pager_params->getQueryParameters();
}
/**
* Prepares variables for pager templates.
*
* Default template: pager.html.twig.
*
* Menu callbacks that display paged query results should use #type => pager
* to retrieve a pager control so that users can view other results. Format a
* list of nearby pages with additional query results.
*
* @param array $variables
* An associative array containing:
* - pager: A render element containing:
* - #tags: An array of labels for the controls in the pager.
* - #element: An optional integer to distinguish between multiple pagers on
* one page.
* - #parameters: An associative array of query string parameters to append
* to the pager links.
* - #route_parameters: An associative array of the route parameters.
* - #quantity: The number of pages in the list.
*/
function template_preprocess_pager(&$variables) {
$element = $variables['pager']['#element'];
$parameters = $variables['pager']['#parameters'];
$quantity = empty($variables['pager']['#quantity']) ? 0 : $variables['pager']['#quantity'];
$route_name = $variables['pager']['#route_name'];
$route_parameters = isset($variables['pager']['#route_parameters']) ? $variables['pager']['#route_parameters'] : [];
/* @var $pager_manager \Drupal\Core\Pager\PagerManagerInterface */
$pager_manager = \Drupal::service('pager.manager');
$pager = $pager_manager->getPager($element);
// Nothing to do if there is no pager.
if (!isset($pager)) {
return;
}
$pager_max = $pager->getTotalPages();
// Nothing to do if there is only one page.
if ($pager_max <= 1) {
return;
}
$tags = $variables['pager']['#tags'];
// Calculate various markers within this pager piece:
// Middle is used to "center" pages around the current page.
$pager_middle = ceil($quantity / 2);
$current_page = $pager->getCurrentPage();
// The current pager is the page we are currently paged to.
$pager_current = $current_page + 1;
// The first pager is the first page listed by this pager piece (re quantity).
$pager_first = $pager_current - $pager_middle + 1;
// The last is the last page listed by this pager piece (re quantity).
$pager_last = $pager_current + $quantity - $pager_middle;
// End of marker calculations.
// Prepare for generation loop.
$i = $pager_first;
if ($pager_last > $pager_max) {
// Adjust "center" if at end of query.
$i = $i + ($pager_max - $pager_last);
$pager_last = $pager_max;
}
if ($i <= 0) {
// Adjust "center" if at start of query.
$pager_last = $pager_last + (1 - $i);
$i = 1;
}
// End of generation loop preparation.
// Create the "first" and "previous" links if we are not on the first page.
if ($current_page > 0) {
$items['first'] = [];
$items['first']['attributes'] = new Attribute();
$options = [
'query' => $pager_manager->getUpdatedParameters($parameters, $element, 0),
];
$items['first']['href'] = Url::fromRoute($route_name, $route_parameters, $options)->toString();
if (isset($tags[0])) {
$items['first']['text'] = $tags[0];
}
$items['previous'] = [];
$items['previous']['attributes'] = new Attribute();
$options = [
'query' => $pager_manager->getUpdatedParameters($parameters, $element, $current_page - 1),
];
$items['previous']['href'] = Url::fromRoute($route_name, $route_parameters, $options)->toString();
if (isset($tags[1])) {
$items['previous']['text'] = $tags[1];
}
}
if ($i != $pager_max) {
// Add an ellipsis if there are further previous pages.
if ($i > 1) {
$variables['ellipses']['previous'] = TRUE;
}
// Now generate the actual pager piece.
for (; $i <= $pager_last && $i <= $pager_max; $i++) {
$options = [
'query' => $pager_manager->getUpdatedParameters($parameters, $element, $i - 1),
];
$items['pages'][$i]['href'] = Url::fromRoute($route_name, $route_parameters, $options)->toString();
$items['pages'][$i]['attributes'] = new Attribute();
if ($i == $pager_current) {
$variables['current'] = $i;
}
}
// Add an ellipsis if there are further next pages.
if ($i < $pager_max + 1) {
$variables['ellipses']['next'] = TRUE;
}
}
// Create the "next" and "last" links if we are not on the last page.
if ($current_page < $pager_max - 1) {
$items['next'] = [];
$items['next']['attributes'] = new Attribute();
$options = [
'query' => $pager_manager->getUpdatedParameters($parameters, $element, $current_page + 1),
];
$items['next']['href'] = Url::fromRoute($route_name, $route_parameters, $options)->toString();
if (isset($tags[3])) {
$items['next']['text'] = $tags[3];
}
$items['last'] = [];
$items['last']['attributes'] = new Attribute();
$options = [
'query' => $pager_manager->getUpdatedParameters($parameters, $element, $pager_max - 1),
];
$items['last']['href'] = Url::fromRoute($route_name, $route_parameters, $options)->toString();
if (isset($tags[4])) {
$items['last']['text'] = $tags[4];
}
}
$variables['items'] = $items;
$variables['heading_id'] = Html::getUniqueId('pagination-heading');
// The rendered link needs to play well with any other query parameter used
// on the page, like exposed filters, so for the cacheability all query
// parameters matter.
$variables['#cache']['contexts'][] = 'url.query_args';
}
/**
* Gets the URL query parameter array of a pager link.
*
* Adds to or adjusts the 'page' URL query parameter so that if you follow the
* link, you'll get page $index for pager $element on the page.
*
* The 'page' URL query parameter is a comma-delimited string, where each value
* is the target content page for the corresponding pager $element. For
* instance, if we have 5 pagers on a single page, and we want to have a link
* to a page that should display the 6th content page for the 3rd pager, and
* the 1st content page for all the other pagers, then the URL query will look
* like this: ?page=0,0,5,0,0 (page numbering starts at zero).
*
* @param array $query
* An associative array of URL query parameters to add to.
* @param int $element
* An integer to distinguish between multiple pagers on one page.
* @param int $index
* The index of the target page, for the given element, in the pager array.
*
* @return array
* The altered $query parameter array.
*
* @deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use
* \Drupal\Core\Pager\PagerManagerInterface::getUpdatedParameters() instead.
*
* @see https://www.drupal.org/node/2779457
* @see \Drupal\Core\Pager\PagerManagerInterface::getUpdatedParameters()
*/
function pager_query_add_page(array $query, $element, $index) {
@trigger_error(__FUNCTION__ . ' is deprecated in drupal:8.8.0 and is removed from drupal:9.0.0. Use \\Drupal\\Core\\Pager\\PagerManagerInterface->getUpdatedParameters() instead. See https://www.drupal.org/node/2779457', E_USER_DEPRECATED);
/* @var $pager_manager \Drupal\Core\Pager\PagerManagerInterface */
$pager_manager = \Drupal::service('pager.manager');
return $pager_manager->getUpdatedParameters($query, $element, $index);
}
Functions
Title | Deprecated | Summary |
---|---|---|
pager_default_initialize | in drupal:8.8.0 and is removed from drupal:9.0.0. Use \Drupal\Core\Pager\PagerManagerInterface->defaultInitialize() instead. |
Initializes a pager. |
pager_find_page | in drupal:8.8.0 and is removed from drupal:9.0.0. Use \Drupal\Core\Pager\PagerParametersInterface->findPage() instead. |
Returns the current page being requested for display within a pager. |
pager_get_query_parameters | in drupal:8.8.0 and is removed from drupal:9.0.0. Use \Drupal\Core\Pager\PagerParametersInterface->getQueryParameters() instead. |
Compose a URL query parameter array for pager links. |
pager_query_add_page | in drupal:8.8.0 and is removed from drupal:9.0.0. Use \Drupal\Core\Pager\PagerManagerInterface::getUpdatedParameters() instead. |
Gets the URL query parameter array of a pager link. |
template_preprocess_pager | Prepares variables for pager templates. |
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