Commit f37ba88b authored by Dries's avatar Dries

- Patch #667112 by pwolanin, David_Rothstein: there is no way to initialize a...

- Patch #667112 by pwolanin, David_Rothstein: there is no way to initialize a pager without running an SQL query.
parent 856a1a53
......@@ -58,7 +58,6 @@ public function __construct(SelectQueryInterface $query, DatabaseConnection $con
* to it.
*/
public function execute() {
global $pager_page_array, $pager_total, $pager_total_items, $pager_limits;
// Add convenience tag to mark that this is an extended query. We have to
// do this in the constructor to ensure that it is set before preExecute()
......@@ -73,21 +72,9 @@ public function execute() {
}
$this->ensureElement();
$page = isset($_GET['page']) ? $_GET['page'] : '';
// Convert comma-separated $page to an array, used by other functions.
$pager_page_array = explode(',', $page);
if (!isset($pager_page_array[$this->element])) {
$pager_page_array[$this->element] = 0;
}
// We calculate the total of pages as ceil(items / limit).
$pager_total_items[$this->element] = $this->getCountQuery()->execute()->fetchField();
$pager_total[$this->element] = ceil($pager_total_items[$this->element] / $this->limit);
$pager_page_array[$this->element] = max(0, min((int) $pager_page_array[$this->element], ((int) $pager_total[$this->element]) - 1));
$pager_limits[$this->element] = $this->limit;
$this->range($pager_page_array[$this->element] * $this->limit, $this->limit);
$total_items = $this->getCountQuery()->execute()->fetchField();
$current_page = pager_default_initialize($total_items, $this->limit, $this->element);
$this->range($current_page * $this->limit, $this->limit);
// Now that we've added our pager-based range instructions, run the query normally.
return $this->query->execute();
......@@ -170,6 +157,124 @@ public function element($element) {
}
}
/**
* Returns the current page being requested for display within a pager.
*
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
*
* @return
* The number of the current requested page, within the pager represented by
* $element. This is determined from the URL query parameter $_GET['page'], or
* 0 by default. Note that this number may differ from the actual page being
* displayed. For example, if a search for "example text" brings up three
* pages of results, but a users visits search/node/example+text?page=10, this
* function will return 10, even though the default pager implementation
* adjusts for this and still displays the third page of search results at
* that URL.
*
* @see pager_default_initialize()
*/
function pager_find_page($element = 0) {
$page = isset($_GET['page']) ? $_GET['page'] : '';
$page_array = explode(',', $page);
if (!isset($page_array[$element])) {
$page_array[$element] = 0;
}
return (int) $page_array[$element];
}
/**
* Initializes a pager for theme('pager').
*
* This function sets up the necessary global variables so that future calls
* to theme('pager') will render a pager that correctly corresponds to the
* items being displayed.
*
* If the items being displayed result from a database query peformed 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 'PagerDefault' extender before
* executing it. For example:
* @code
* $query = db_select('some_table')->extend('PagerDefault');
* @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 page callback
* 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 = variable_get('mymodule_num_per_page', 10);
* $page = pager_default_initialize($total, $num_per_page);
*
* // Next, retrieve and display the items for the current page.
* $offset = $num_per_page * $page;
* $result = mymodule_select("SELECT * FROM data " . $where . " LIMIT %d, %d", $offset, $num_per_page)->fetchAll();
* $output = theme('mymodule_results', array('result' => $result));
*
* // Finally, display the pager controls, and return.
* $output .= theme('pager');
* return $output;
* @endcode
*
* A second example involves a page callback 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 = variable_get('mymodule_num_per_page', 10);
* $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);
*
* // Display the search results.
* $output = theme('search_results', array('results' => $result->data, 'type' => 'remote'));
*
* // Finally, display the pager controls, and return.
* $output .= theme('pager');
* return $output;
* @endcode
*
* @param $total
* The total number of items to be paged.
* @param $limit
* The number of items the calling code will display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
*
* @return
* The number of the current page, within the pager represented by $element.
* This is determined from the URL query parameter $_GET['page'], or 0 by
* default. However, if a page that does not correspond to the actual range
* of the result set was requested, this function will return the closest
* page actually within the result set.
*/
function pager_default_initialize($total, $limit, $element = 0) {
global $pager_page_array, $pager_total, $pager_total_items, $pager_limits;
$page = pager_find_page($element);
// We calculate the total of pages as ceil(items / limit).
$pager_total_items[$element] = $total;
$pager_total[$element] = ceil($pager_total_items[$element] / $limit);
$pager_page_array[$element] = max(0, min($page, ((int) $pager_total[$element]) - 1));
$pager_limits[$element] = $limit;
return $pager_page_array[$element];
}
/**
* Compose a URL query parameter array for pager links.
*
......
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