| 1 | <?php |
| 2 | // $Id: pager.inc,v 1.69 2009/08/11 16:43:11 webchick Exp $ |
| 3 | |
| 4 | /** |
| 5 | * @file |
| 6 | * Functions to aid in presenting database results as a set of pages. |
| 7 | */ |
| 8 | |
| 9 | |
| 10 | /** |
| 11 | * Query extender for pager queries. |
| 12 | * |
| 13 | * This is the "default" pager mechanism. It creates a paged query with a fixed |
| 14 | * number of entries per page. |
| 15 | */ |
| 16 | class PagerDefault extends SelectQueryExtender { |
| 17 | |
| 18 | /** |
| 19 | * The highest element we've autogenerated so far. |
| 20 | * |
| 21 | * @var int |
| 22 | */ |
| 23 | static protected $maxElement = 0; |
| 24 | |
| 25 | /** |
| 26 | * The number of elements per page to allow. |
| 27 | * |
| 28 | * @var int |
| 29 | */ |
| 30 | protected $limit = 10; |
| 31 | |
| 32 | /** |
| 33 | * The unique ID of this pager on this page. |
| 34 | * |
| 35 | * @var int |
| 36 | */ |
| 37 | protected $element = NULL; |
| 38 | |
| 39 | /** |
| 40 | * The count query that will be used for this pager. |
| 41 | * |
| 42 | * @var SelectQueryInterface |
| 43 | */ |
| 44 | protected $customCountQuery = FALSE; |
| 45 | |
| 46 | /** |
| 47 | * Override the execute method. |
| 48 | * |
| 49 | * Before we run the query, we need to add pager-based range() instructions |
| 50 | * to it. |
| 51 | */ |
| 52 | public function execute() { |
| 53 | global $pager_page_array, $pager_total, $pager_total_items, $pager_limits; |
| 54 | |
| 55 | // A NULL limit is the "kill switch" for pager queries. |
| 56 | if (empty($this->limit)) { |
| 57 | return; |
| 58 | } |
| 59 | $this->ensureElement(); |
| 60 | |
| 61 | $page = isset($_GET['page']) ? $_GET['page'] : ''; |
| 62 | |
| 63 | // Convert comma-separated $page to an array, used by other functions. |
| 64 | $pager_page_array = explode(',', $page); |
| 65 | |
| 66 | if (!isset($pager_page_array[$this->element])) { |
| 67 | $pager_page_array[$this->element] = 0; |
| 68 | } |
| 69 | |
| 70 | // We calculate the total of pages as ceil(items / limit). |
| 71 | $pager_total_items[$this->element] = $this->getCountQuery()->execute()->fetchField(); |
| 72 | $pager_total[$this->element] = ceil($pager_total_items[$this->element] / $this->limit); |
| 73 | $pager_page_array[$this->element] = max(0, min((int)$pager_page_array[$this->element], ((int)$pager_total[$this->element]) - 1)); |
| 74 | $pager_limits[$this->element] = $this->limit; |
| 75 | $this->range($pager_page_array[$this->element] * $this->limit, $this->limit); |
| 76 | |
| 77 | // Now that we've added our pager-based range instructions, run the query normally. |
| 78 | return $this->query->execute(); |
| 79 | } |
| 80 | |
| 81 | /** |
| 82 | * Ensure that there is an element associated with this query. |
| 83 | * |
| 84 | * After running this query, access $this->element to get the element for this |
| 85 | * query. |
| 86 | */ |
| 87 | protected function ensureElement() { |
| 88 | if (!empty($this->element)) { |
| 89 | return; |
| 90 | } |
| 91 | |
| 92 | $this->element = self::$maxElement++; |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * Specify the count query object to use for this pager. |
| 97 | * |
| 98 | * You will rarely need to specify a count query directly. If not specified, |
| 99 | * one is generated off of the pager query itself. |
| 100 | * |
| 101 | * @param SelectQueryInterface $query |
| 102 | * The count query object. It must return a single row with a single column, |
| 103 | * which is the total number of records. |
| 104 | */ |
| 105 | public function setCountQuery(SelectQueryInterface $query) { |
| 106 | $this->customCountQuery = $query; |
| 107 | } |
| 108 | |
| 109 | /** |
| 110 | * Retrieve the count query for this pager. |
| 111 | * |
| 112 | * The count query may be specified manually or, by default, taken from the |
| 113 | * query we are extending. |
| 114 | * |
| 115 | * @return |
| 116 | * A count SelectQueryInterface object. |
| 117 | */ |
| 118 | protected function getCountQuery() { |
| 119 | if ($this->customCountQuery) { |
| 120 | return $this->customCountQuery; |
| 121 | } |
| 122 | else { |
| 123 | return $this->query->countQuery(); |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * Specify the maximum number of elements per page for this query. |
| 129 | * |
| 130 | * The default if not specified is 10 items per page. |
| 131 | * |
| 132 | * @param $limit |
| 133 | * An integer specifying the number of elements per page. If passed a false |
| 134 | * value (FALSE, 0, NULL), the pager is disabled. |
| 135 | */ |
| 136 | public function limit($limit = 10) { |
| 137 | $this->limit = $limit; |
| 138 | return $this; |
| 139 | } |
| 140 | |
| 141 | /** |
| 142 | * Specify the element ID for this pager query. |
| 143 | * |
| 144 | * The element is used to differentiate different pager queries on the same |
| 145 | * page so that they may be operated independently. If you do not specify an |
| 146 | * element, every pager query on the page will get a unique element. If for |
| 147 | * whatever reason you want to explicitly define an element for a given query, |
| 148 | * you may do so here. |
| 149 | * |
| 150 | * @param $element |
| 151 | */ |
| 152 | public function element($element) { |
| 153 | $this->element = $element; |
| 154 | return $this; |
| 155 | } |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Perform a paged database query. |
| 160 | * |
| 161 | * Use this function when doing select queries you wish to be able to page. The |
| 162 | * pager uses LIMIT-based queries to fetch only the records required to render a |
| 163 | * certain page. However, it has to learn the total number of records returned |
| 164 | * by the query to compute the number of pages (the number of records / records |
| 165 | * per page). This is done by inserting "COUNT(*)" in the original query. For |
| 166 | * example, the query "SELECT nid, type FROM node WHERE status = '1' ORDER BY |
| 167 | * sticky DESC, created DESC" would be rewritten to read "SELECT COUNT(*) FROM |
| 168 | * node WHERE status = '1' ORDER BY sticky DESC, created DESC". Rewriting the |
| 169 | * query is accomplished using a regular expression. |
| 170 | * |
| 171 | * Unfortunately, the rewrite rule does not always work as intended for queries |
| 172 | * that already have a "COUNT(*)" or a "GROUP BY" clause, and possibly for |
| 173 | * other complex queries. In those cases, you can optionally pass a query that |
| 174 | * will be used to count the records. |
| 175 | * |
| 176 | * For example, if you want to page the query "SELECT COUNT(*), TYPE FROM node |
| 177 | * GROUP BY TYPE", pager_query() would invoke the incorrect query "SELECT |
| 178 | * COUNT(*) FROM node GROUP BY TYPE". So instead, you should pass "SELECT |
| 179 | * COUNT(DISTINCT(TYPE)) FROM node" as the optional $count_query parameter. |
| 180 | * |
| 181 | * @param $query |
| 182 | * The SQL query that needs paging. |
| 183 | * @param $limit |
| 184 | * The number of query results to display per page. |
| 185 | * @param $element |
| 186 | * An optional integer to distinguish between multiple pagers on one page. |
| 187 | * @param $count_query |
| 188 | * An SQL query used to count matching records. |
| 189 | * @param ... |
| 190 | * A variable number of arguments which are substituted into the query (and |
| 191 | * the count query) using printf() syntax. Instead of a variable number of |
| 192 | * query arguments, you may also pass a single array containing the query |
| 193 | * arguments. |
| 194 | * @return |
| 195 | * A database query result resource, or FALSE if the query was not executed |
| 196 | * correctly. |
| 197 | * |
| 198 | * @ingroup database |
| 199 | */ |
| 200 | function pager_query($query, $limit = 10, $element = 0, $count_query = NULL) { |
| 201 | global $pager_page_array, $pager_total, $pager_total_items, $pager_limits; |
| 202 | $page = isset($_GET['page']) ? $_GET['page'] : ''; |
| 203 | |
| 204 | // Substitute in query arguments. |
| 205 | $args = func_get_args(); |
| 206 | $args = array_slice($args, 4); |
| 207 | // Alternative syntax for '...' |
| 208 | if (isset($args[0]) && is_array($args[0])) { |
| 209 | $args = $args[0]; |
| 210 | } |
| 211 | |
| 212 | // Construct a count query if none was given. |
| 213 | if (!isset($count_query)) { |
| 214 | $count_query = preg_replace(array('/SELECT.*?FROM /As', '/ORDER BY .*/'), array('SELECT COUNT(*) FROM ', ''), $query); |
| 215 | } |
| 216 | |
| 217 | // Convert comma-separated $page to an array, used by other functions. |
| 218 | $pager_page_array = explode(',', $page); |
| 219 | |
| 220 | // We calculate the total of pages as ceil(items / limit). |
| 221 | $pager_total_items[$element] = db_query($count_query, $args)->fetchField(); |
| 222 | $pager_total[$element] = ceil($pager_total_items[$element] / $limit); |
| 223 | $pager_page_array[$element] = max(0, min((int)$pager_page_array[$element], ((int)$pager_total[$element]) - 1)); |
| 224 | $pager_limits[$element] = $limit; |
| 225 | return db_query_range($query, $args, $pager_page_array[$element] * $limit, $limit); |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * Compose a query string to append to pager requests. |
| 230 | * |
| 231 | * @return |
| 232 | * A query string that consists of all components of the current page request |
| 233 | * except for those pertaining to paging. |
| 234 | */ |
| 235 | function pager_get_querystring() { |
| 236 | static $string = NULL; |
| 237 | if (!isset($string)) { |
| 238 | $string = drupal_query_string_encode($_REQUEST, array_merge(array('q', 'page'), array_keys($_COOKIE))); |
| 239 | } |
| 240 | return $string; |
| 241 | } |
| 242 | |
| 243 | /** |
| 244 | * Format a query pager. |
| 245 | * |
| 246 | * Menu callbacks that display paged query results should call theme('pager') to |
| 247 | * retrieve a pager control so that users can view other results. |
| 248 | * Format a list of nearby pages with additional query results. |
| 249 | * |
| 250 | * @param $tags |
| 251 | * An array of labels for the controls in the pager. |
| 252 | * @param $element |
| 253 | * An optional integer to distinguish between multiple pagers on one page. |
| 254 | * @param $parameters |
| 255 | * An associative array of query string parameters to append to the pager links. |
| 256 | * @param $quantity |
| 257 | * The number of pages in the list. |
| 258 | * @return |
| 259 | * An HTML string that generates the query pager. |
| 260 | * |
| 261 | * @ingroup themeable |
| 262 | */ |
| 263 | function theme_pager($tags = array(), $element = 0, $parameters = array(), $quantity = 9) { |
| 264 | global $pager_page_array, $pager_total; |
| 265 | |
| 266 | // Calculate various markers within this pager piece: |
| 267 | // Middle is used to "center" pages around the current page. |
| 268 | $pager_middle = ceil($quantity / 2); |
| 269 | // current is the page we are currently paged to |
| 270 | $pager_current = $pager_page_array[$element] + 1; |
| 271 | // first is the first page listed by this pager piece (re quantity) |
| 272 | $pager_first = $pager_current - $pager_middle + 1; |
| 273 | // last is the last page listed by this pager piece (re quantity) |
| 274 | $pager_last = $pager_current + $quantity - $pager_middle; |
| 275 | // max is the maximum page number |
| 276 | $pager_max = $pager_total[$element]; |
| 277 | // End of marker calculations. |
| 278 | |
| 279 | // Prepare for generation loop. |
| 280 | $i = $pager_first; |
| 281 | if ($pager_last > $pager_max) { |
| 282 | // Adjust "center" if at end of query. |
| 283 | $i = $i + ($pager_max - $pager_last); |
| 284 | $pager_last = $pager_max; |
| 285 | } |
| 286 | if ($i <= 0) { |
| 287 | // Adjust "center" if at start of query. |
| 288 | $pager_last = $pager_last + (1 - $i); |
| 289 | $i = 1; |
| 290 | } |
| 291 | // End of generation loop preparation. |
| 292 | |
| 293 | $li_first = theme('pager_first', (isset($tags[0]) ? $tags[0] : t('« first')), $element, $parameters); |
| 294 | $li_previous = theme('pager_previous', (isset($tags[1]) ? $tags[1] : t('‹ previous')), $element, 1, $parameters); |
| 295 | $li_next = theme('pager_next', (isset($tags[3]) ? $tags[3] : t('next ›')), $element, 1, $parameters); |
| 296 | $li_last = theme('pager_last', (isset($tags[4]) ? $tags[4] : t('last »')), $element, $parameters); |
| 297 | |
| 298 | if ($pager_total[$element] > 1) { |
| 299 | if ($li_first) { |
| 300 | $items[] = array( |
| 301 | 'class' => 'pager-first', |
| 302 | 'data' => $li_first, |
| 303 | ); |
| 304 | } |
| 305 | if ($li_previous) { |
| 306 | $items[] = array( |
| 307 | 'class' => 'pager-previous', |
| 308 | 'data' => $li_previous, |
| 309 | ); |
| 310 | } |
| 311 | |
| 312 | // When there is more than one page, create the pager list. |
| 313 | if ($i != $pager_max) { |
| 314 | if ($i > 1) { |
| 315 | $items[] = array( |
| 316 | 'class' => 'pager-ellipsis', |
| 317 | 'data' => '…', |
| 318 | ); |
| 319 | } |
| 320 | // Now generate the actual pager piece. |
| 321 | for (; $i <= $pager_last && $i <= $pager_max; $i++) { |
| 322 | if ($i < $pager_current) { |
| 323 | $items[] = array( |
| 324 | 'class' => 'pager-item', |
| 325 | 'data' => theme('pager_previous', $i, $element, ($pager_current - $i), $parameters), |
| 326 | ); |
| 327 | } |
| 328 | if ($i == $pager_current) { |
| 329 | $items[] = array( |
| 330 | 'class' => 'pager-current', |
| 331 | 'data' => $i, |
| 332 | ); |
| 333 | } |
| 334 | if ($i > $pager_current) { |
| 335 | $items[] = array( |
| 336 | 'class' => 'pager-item', |
| 337 | 'data' => theme('pager_next', $i, $element, ($i - $pager_current), $parameters), |
| 338 | ); |
| 339 | } |
| 340 | } |
| 341 | if ($i < $pager_max) { |
| 342 | $items[] = array( |
| 343 | 'class' => 'pager-ellipsis', |
| 344 | 'data' => '…', |
| 345 | ); |
| 346 | } |
| 347 | } |
| 348 | // End generation. |
| 349 | if ($li_next) { |
| 350 | $items[] = array( |
| 351 | 'class' => 'pager-next', |
| 352 | 'data' => $li_next, |
| 353 | ); |
| 354 | } |
| 355 | if ($li_last) { |
| 356 | $items[] = array( |
| 357 | 'class' => 'pager-last', |
| 358 | 'data' => $li_last, |
| 359 | ); |
| 360 | } |
| 361 | return theme('item_list', $items, NULL, 'ul', array('class' => 'pager')); |
| 362 | } |
| 363 | } |
| 364 | |
| 365 | |
| 366 | /** |
| 367 | * @name Pager pieces |
| 368 | * @{ |
| 369 | * Use these pieces to construct your own custom pagers in your theme. Note that |
| 370 | * you should NOT modify this file to customize your pager. |
| 371 | */ |
| 372 | |
| 373 | /** |
| 374 | * Format a "first page" link. |
| 375 | * |
| 376 | * @param $text |
| 377 | * The name (or image) of the link. |
| 378 | * @param $element |
| 379 | * An optional integer to distinguish between multiple pagers on one page. |
| 380 | * @param $parameters |
| 381 | * An associative array of query string parameters to append to the pager links. |
| 382 | * @return |
| 383 | * An HTML string that generates this piece of the query pager. |
| 384 | * |
| 385 | * @ingroup themeable |
| 386 | */ |
| 387 | function theme_pager_first($text, $element = 0, $parameters = array()) { |
| 388 | global $pager_page_array; |
| 389 | $output = ''; |
| 390 | |
| 391 | // If we are anywhere but the first page |
| 392 | if ($pager_page_array[$element] > 0) { |
| 393 | $output = theme('pager_link', $text, pager_load_array(0, $element, $pager_page_array), $element, $parameters); |
| 394 | } |
| 395 | |
| 396 | return $output; |
| 397 | } |
| 398 | |
| 399 | /** |
| 400 | * Format a "previous page" link. |
| 401 | * |
| 402 | * @param $text |
| 403 | * The name (or image) of the link. |
| 404 | * @param $element |
| 405 | * An optional integer to distinguish between multiple pagers on one page. |
| 406 | * @param $interval |
| 407 | * The number of pages to move backward when the link is clicked. |
| 408 | * @param $parameters |
| 409 | * An associative array of query string parameters to append to the pager links. |
| 410 | * @return |
| 411 | * An HTML string that generates this piece of the query pager. |
| 412 | * |
| 413 | * @ingroup themeable |
| 414 | */ |
| 415 | function theme_pager_previous($text, $element = 0, $interval = 1, $parameters = array()) { |
| 416 | global $pager_page_array; |
| 417 | $output = ''; |
| 418 | |
| 419 | // If we are anywhere but the first page |
| 420 | if ($pager_page_array[$element] > 0) { |
| 421 | $page_new = pager_load_array($pager_page_array[$element] - $interval, $element, $pager_page_array); |
| 422 | |
| 423 | // If the previous page is the first page, mark the link as such. |
| 424 | if ($page_new[$element] == 0) { |
| 425 | $output = theme('pager_first', $text, $element, $parameters); |
| 426 | } |
| 427 | // The previous page is not the first page. |
| 428 | else { |
| 429 | $output = theme('pager_link', $text, $page_new, $element, $parameters); |
| 430 | } |
| 431 | } |
| 432 | |
| 433 | return $output; |
| 434 | } |
| 435 | |
| 436 | /** |
| 437 | * Format a "next page" link. |
| 438 | * |
| 439 | * @param $text |
| 440 | * The name (or image) of the link. |
| 441 | * @param $element |
| 442 | * An optional integer to distinguish between multiple pagers on one page. |
| 443 | * @param $interval |
| 444 | * The number of pages to move forward when the link is clicked. |
| 445 | * @param $parameters |
| 446 | * An associative array of query string parameters to append to the pager links. |
| 447 | * @return |
| 448 | * An HTML string that generates this piece of the query pager. |
| 449 | * |
| 450 | * @ingroup themeable |
| 451 | */ |
| 452 | function theme_pager_next($text, $element = 0, $interval = 1, $parameters = array()) { |
| 453 | global $pager_page_array, $pager_total; |
| 454 | $output = ''; |
| 455 | |
| 456 | // If we are anywhere but the last page |
| 457 | if ($pager_page_array[$element] < ($pager_total[$element] - 1)) { |
| 458 | $page_new = pager_load_array($pager_page_array[$element] + $interval, $element, $pager_page_array); |
| 459 | // If the next page is the last page, mark the link as such. |
| 460 | if ($page_new[$element] == ($pager_total[$element] - 1)) { |
| 461 | $output = theme('pager_last', $text, $element, $parameters); |
| 462 | } |
| 463 | // The next page is not the last page. |
| 464 | else { |
| 465 | $output = theme('pager_link', $text, $page_new, $element, $parameters); |
| 466 | } |
| 467 | } |
| 468 | |
| 469 | return $output; |
| 470 | } |
| 471 | |
| 472 | /** |
| 473 | * Format a "last page" link. |
| 474 | * |
| 475 | * @param $text |
| 476 | * The name (or image) of the link. |
| 477 | * @param $element |
| 478 | * An optional integer to distinguish between multiple pagers on one page. |
| 479 | * @param $parameters |
| 480 | * An associative array of query string parameters to append to the pager links. |
| 481 | * @return |
| 482 | * An HTML string that generates this piece of the query pager. |
| 483 | * |
| 484 | * @ingroup themeable |
| 485 | */ |
| 486 | function theme_pager_last($text, $element = 0, $parameters = array()) { |
| 487 | global $pager_page_array, $pager_total; |
| 488 | $output = ''; |
| 489 | |
| 490 | // If we are anywhere but the last page |
| 491 | if ($pager_page_array[$element] < ($pager_total[$element] - 1)) { |
| 492 | $output = theme('pager_link', $text, pager_load_array($pager_total[$element] - 1, $element, $pager_page_array), $element, $parameters); |
| 493 | } |
| 494 | |
| 495 | return $output; |
| 496 | } |
| 497 | |
| 498 | |
| 499 | /** |
| 500 | * Format a link to a specific query result page. |
| 501 | * |
| 502 | * @param $page_new |
| 503 | * The first result to display on the linked page. |
| 504 | * @param $element |
| 505 | * An optional integer to distinguish between multiple pagers on one page. |
| 506 | * @param $parameters |
| 507 | * An associative array of query string parameters to append to the pager link. |
| 508 | * @param $attributes |
| 509 | * An associative array of HTML attributes to apply to a pager anchor tag. |
| 510 | * @return |
| 511 | * An HTML string that generates the link. |
| 512 | * |
| 513 | * @ingroup themeable |
| 514 | */ |
| 515 | function theme_pager_link($text, $page_new, $element, $parameters = array(), $attributes = array()) { |
| 516 | $page = isset($_GET['page']) ? $_GET['page'] : ''; |
| 517 | if ($new_page = implode(',', pager_load_array($page_new[$element], $element, explode(',', $page)))) { |
| 518 | $parameters['page'] = $new_page; |
| 519 | } |
| 520 | |
| 521 | $query = array(); |
| 522 | if (count($parameters)) { |
| 523 | $query[] = drupal_query_string_encode($parameters, array()); |
| 524 | } |
| 525 | $querystring = pager_get_querystring(); |
| 526 | if ($querystring != '') { |
| 527 | $query[] = $querystring; |
| 528 | } |
| 529 | |
| 530 | // Set each pager link title |
| 531 | if (!isset($attributes['title'])) { |
| 532 | static $titles = NULL; |
| 533 | if (!isset($titles)) { |
| 534 | $titles = array( |
| 535 | t('« first') => t('Go to first page'), |
| 536 | t('‹ previous') => t('Go to previous page'), |
| 537 | t('next ›') => t('Go to next page'), |
| 538 | t('last »') => t('Go to last page'), |
| 539 | ); |
| 540 | } |
| 541 | if (isset($titles[$text])) { |
| 542 | $attributes['title'] = $titles[$text]; |
| 543 | } |
| 544 | elseif (is_numeric($text)) { |
| 545 | $attributes['title'] = t('Go to page @number', array('@number' => $text)); |
| 546 | } |
| 547 | } |
| 548 | |
| 549 | return l($text, $_GET['q'], array('attributes' => $attributes, 'query' => count($query) ? implode('&', $query) : NULL)); |
| 550 | } |
| 551 | |
| 552 | /** |
| 553 | * @} End of "Pager pieces". |
| 554 | */ |
| 555 | |
| 556 | /** |
| 557 | * Helper function |
| 558 | * |
| 559 | * Copies $old_array to $new_array and sets $new_array[$element] = $value |
| 560 | * Fills in $new_array[0 .. $element - 1] = 0 |
| 561 | */ |
| 562 | function pager_load_array($value, $element, $old_array) { |
| 563 | $new_array = $old_array; |
| 564 | // Look for empty elements. |
| 565 | for ($i = 0; $i < $element; $i++) { |
| 566 | if (!$new_array[$i]) { |
| 567 | // Load found empty element with 0. |
| 568 | $new_array[$i] = 0; |
| 569 | } |
| 570 | } |
| 571 | // Update the changed element. |
| 572 | $new_array[$element] = (int)$value; |
| 573 | return $new_array; |
| 574 | } |
| 575 |