drupal/includes/pager.inc

435 lines
14 KiB
PHP
Raw Blame History

This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

<?php
// $Id$
/**
* @file
* Functions to aid in presenting database results as a set of pages.
*/
/**
* Perform a paged database query.
*
* Use this function when doing select queries you wish to be able to page. The
* pager uses LIMIT-based queries to fetch only the records required to render a
* certain page. However, it has to learn the total number of records returned
* by the query to compute the number of pages (the number of records / records
* per page). This is done by inserting "COUNT(*)" in the original query. For
* example, the query "SELECT nid, type FROM node WHERE status = '1' ORDER BY
* sticky DESC, created DESC" would be rewritten to read "SELECT COUNT(*) FROM
* node WHERE status = '1' ORDER BY sticky DESC, created DESC". Rewriting the
* query is accomplished using a regular expression.
*
* Unfortunately, the rewrite rule does not always work as intended for queries
* that already have a "COUNT(*)" or a "GROUP BY" clause, and possibly for
* other complex queries. In those cases, you can optionally pass a query that
* will be used to count the records.
*
* For example, if you want to page the query "SELECT COUNT(*), TYPE FROM node
* GROUP BY TYPE", pager_query() would invoke the incorrect query "SELECT
* COUNT(*) FROM node GROUP BY TYPE". So instead, you should pass "SELECT
* COUNT(DISTINCT(TYPE)) FROM node" as the optional $count_query parameter.
*
* @param $query
* The SQL query that needs paging.
* @param $limit
* The number of query results to display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $count_query
* An SQL query used to count matching records.
* @param ...
* A variable number of arguments which are substituted into the query (and
* the count query) using printf() syntax. Instead of a variable number of
* query arguments, you may also pass a single array containing the query
* arguments.
* @return
* A database query result resource, or FALSE if the query was not executed
* correctly.
*
* @ingroup database
*/
function pager_query($query, $limit = 10, $element = 0, $count_query = NULL) {
global $pager_page_array, $pager_total, $pager_total_items;
$page = isset($_GET['page']) ? $_GET['page'] : '';
// Substitute in query arguments.
$args = func_get_args();
$args = array_slice($args, 4);
// Alternative syntax for '...'
if (isset($args[0]) && is_array($args[0])) {
$args = $args[0];
}
// Construct a count query if none was given.
if (!isset($count_query)) {
$count_query = preg_replace(array('/SELECT.*?FROM /As', '/ORDER BY .*/'), array('SELECT COUNT(*) FROM ', ''), $query);
}
// Convert comma-separated $page to an array, used by other functions.
$pager_page_array = explode(',', $page);
// We calculate the total of pages as ceil(items / limit).
$pager_total_items[$element] = db_result(db_query($count_query, $args));
$pager_total[$element] = ceil($pager_total_items[$element] / $limit);
$pager_page_array[$element] = max(0, min((int)$pager_page_array[$element], ((int)$pager_total[$element]) - 1));
return db_query_range($query, $args, $pager_page_array[$element] * $limit, $limit);
}
/**
* Compose a query string to append to pager requests.
*
* @return
* A query string that consists of all components of the current page request
* except for those pertaining to paging.
*/
function pager_get_querystring() {
static $string = NULL;
if (!isset($string)) {
$string = drupal_query_string_encode($_REQUEST, array_merge(array('q', 'page'), array_keys($_COOKIE)));
}
return $string;
}
/**
* Format a query pager.
*
* Menu callbacks that display paged query results should call theme('pager') to
* retrieve a pager control so that users can view other results.
* Format a list of nearby pages with additional query results.
*
* @param $tags
* An array of labels for the controls in the pager.
* @param $limit
* The number of query results to display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $parameters
* An associative array of query string parameters to append to the pager links.
* @param $quantity
* The number of pages in the list.
* @return
* An HTML string that generates the query pager.
*
* @ingroup themeable
*/
function theme_pager($tags = array(), $limit = 10, $element = 0, $parameters = array(), $quantity = 9) {
global $pager_page_array, $pager_total;
// Calculate various markers within this pager piece:
// Middle is used to "center" pages around the current page.
$pager_middle = ceil($quantity / 2);
// current is the page we are currently paged to
$pager_current = $pager_page_array[$element] + 1;
// first is the first page listed by this pager piece (re quantity)
$pager_first = $pager_current - $pager_middle + 1;
// last is the last page listed by this pager piece (re quantity)
$pager_last = $pager_current + $quantity - $pager_middle;
// max is the maximum page number
$pager_max = $pager_total[$element];
// 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.
$li_first = theme('pager_first', (isset($tags[0]) ? $tags[0] : t('« first')), $limit, $element, $parameters);
$li_previous = theme('pager_previous', (isset($tags[1]) ? $tags[1] : t(' previous')), $limit, $element, 1, $parameters);
$li_next = theme('pager_next', (isset($tags[3]) ? $tags[3] : t('next ')), $limit, $element, 1, $parameters);
$li_last = theme('pager_last', (isset($tags[4]) ? $tags[4] : t('last »')), $limit, $element, $parameters);
if ($pager_total[$element] > 1) {
if ($li_first) {
$items[] = array(
'class' => 'pager-first',
'data' => $li_first,
);
}
if ($li_previous) {
$items[] = array(
'class' => 'pager-previous',
'data' => $li_previous,
);
}
// When there is more than one page, create the pager list.
if ($i != $pager_max) {
if ($i > 1) {
$items[] = array(
'class' => 'pager-ellipsis',
'data' => '…',
);
}
// Now generate the actual pager piece.
for (; $i <= $pager_last && $i <= $pager_max; $i++) {
if ($i < $pager_current) {
$items[] = array(
'class' => 'pager-item',
'data' => theme('pager_previous', $i, $limit, $element, ($pager_current - $i), $parameters),
);
}
if ($i == $pager_current) {
$items[] = array(
'class' => 'pager-current',
'data' => $i,
);
}
if ($i > $pager_current) {
$items[] = array(
'class' => 'pager-item',
'data' => theme('pager_next', $i, $limit, $element, ($i - $pager_current), $parameters),
);
}
}
if ($i < $pager_max) {
$items[] = array(
'class' => 'pager-ellipsis',
'data' => '…',
);
}
}
// End generation.
if ($li_next) {
$items[] = array(
'class' => 'pager-next',
'data' => $li_next,
);
}
if ($li_last) {
$items[] = array(
'class' => 'pager-last',
'data' => $li_last,
);
}
return theme('item_list', $items, NULL, 'ul', array('class' => 'pager'));
}
}
/**
* @name Pager pieces
* @{
* Use these pieces to construct your own custom pagers in your theme. Note that
* you should NOT modify this file to customize your pager.
*/
/**
* Format a "first page" link.
*
* @param $text
* The name (or image) of the link.
* @param $limit
* The number of query results to display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $parameters
* An associative array of query string parameters to append to the pager links.
* @return
* An HTML string that generates this piece of the query pager.
*
* @ingroup themeable
*/
function theme_pager_first($text, $limit, $element = 0, $parameters = array()) {
global $pager_page_array;
$output = '';
// If we are anywhere but the first page
if ($pager_page_array[$element] > 0) {
$output = theme('pager_link', $text, pager_load_array(0, $element, $pager_page_array), $element, $parameters);
}
return $output;
}
/**
* Format a "previous page" link.
*
* @param $text
* The name (or image) of the link.
* @param $limit
* The number of query results to display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $interval
* The number of pages to move backward when the link is clicked.
* @param $parameters
* An associative array of query string parameters to append to the pager links.
* @return
* An HTML string that generates this piece of the query pager.
*
* @ingroup themeable
*/
function theme_pager_previous($text, $limit, $element = 0, $interval = 1, $parameters = array()) {
global $pager_page_array;
$output = '';
// If we are anywhere but the first page
if ($pager_page_array[$element] > 0) {
$page_new = pager_load_array($pager_page_array[$element] - $interval, $element, $pager_page_array);
// If the previous page is the first page, mark the link as such.
if ($page_new[$element] == 0) {
$output = theme('pager_first', $text, $limit, $element, $parameters);
}
// The previous page is not the first page.
else {
$output = theme('pager_link', $text, $page_new, $element, $parameters);
}
}
return $output;
}
/**
* Format a "next page" link.
*
* @param $text
* The name (or image) of the link.
* @param $limit
* The number of query results to display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $interval
* The number of pages to move forward when the link is clicked.
* @param $parameters
* An associative array of query string parameters to append to the pager links.
* @return
* An HTML string that generates this piece of the query pager.
*
* @ingroup themeable
*/
function theme_pager_next($text, $limit, $element = 0, $interval = 1, $parameters = array()) {
global $pager_page_array, $pager_total;
$output = '';
// If we are anywhere but the last page
if ($pager_page_array[$element] < ($pager_total[$element] - 1)) {
$page_new = pager_load_array($pager_page_array[$element] + $interval, $element, $pager_page_array);
// If the next page is the last page, mark the link as such.
if ($page_new[$element] == ($pager_total[$element] - 1)) {
$output = theme('pager_last', $text, $limit, $element, $parameters);
}
// The next page is not the last page.
else {
$output = theme('pager_link', $text, $page_new, $element, $parameters);
}
}
return $output;
}
/**
* Format a "last page" link.
*
* @param $text
* The name (or image) of the link.
* @param $limit
* The number of query results to display per page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $parameters
* An associative array of query string parameters to append to the pager links.
* @return
* An HTML string that generates this piece of the query pager.
*
* @ingroup themeable
*/
function theme_pager_last($text, $limit, $element = 0, $parameters = array()) {
global $pager_page_array, $pager_total;
$output = '';
// If we are anywhere but the last page
if ($pager_page_array[$element] < ($pager_total[$element] - 1)) {
$output = theme('pager_link', $text, pager_load_array($pager_total[$element] - 1, $element, $pager_page_array), $element, $parameters);
}
return $output;
}
/**
* Format a link to a specific query result page.
*
* @param $page_new
* The first result to display on the linked page.
* @param $element
* An optional integer to distinguish between multiple pagers on one page.
* @param $parameters
* An associative array of query string parameters to append to the pager link.
* @param $attributes
* An associative array of HTML attributes to apply to a pager anchor tag.
* @return
* An HTML string that generates the link.
*
* @ingroup themeable
*/
function theme_pager_link($text, $page_new, $element, $parameters = array(), $attributes = array()) {
$page = isset($_GET['page']) ? $_GET['page'] : '';
if ($new_page = implode(',', pager_load_array($page_new[$element], $element, explode(',', $page)))) {
$parameters['page'] = $new_page;
}
$query = array();
if (count($parameters)) {
$query[] = drupal_query_string_encode($parameters, array());
}
$querystring = pager_get_querystring();
if ($querystring != '') {
$query[] = $querystring;
}
// Set each pager link title
if (!isset($attributes['title'])) {
static $titles = NULL;
if (!isset($titles)) {
$titles = array(
t('« first') => t('Go to first page'),
t(' previous') => t('Go to previous page'),
t('next ') => t('Go to next page'),
t('last »') => t('Go to last page'),
);
}
if (isset($titles[$text])) {
$attributes['title'] = $titles[$text];
}
elseif (is_numeric($text)) {
$attributes['title'] = t('Go to page @number', array('@number' => $text));
}
}
return l($text, $_GET['q'], array('attributes' => $attributes, 'query' => count($query) ? implode('&', $query) : NULL));
}
/**
* @} End of "Pager pieces".
*/
/**
* Helper function
*
* Copies $old_array to $new_array and sets $new_array[$element] = $value
* Fills in $new_array[0 .. $element - 1] = 0
*/
function pager_load_array($value, $element, $old_array) {
$new_array = $old_array;
// Look for empty elements.
for ($i = 0; $i < $element; $i++) {
if (!$new_array[$i]) {
// Load found empty element with 0.
$new_array[$i] = 0;
}
}
// Update the changed element.
$new_array[$element] = (int)$value;
return $new_array;
}