[nycphp-talk] Problem with Pagination
Phillip Powell
phillip.powell at adnet-sys.com
Thu Jun 3 15:58:55 EDT 2004
Joe Crawford Jr. wrote:
>Phillip,
>
>after taking a look at your code i have come to this conclusion and may be
>incorrect
>
>your code :
>
>$html .= ($offset + (int)$displayItemLimit > @sizeof($this->result))
>
>shouldnt that be
>
>$html .= (($offset + (int)$displayItemLimit) > @sizeof($this->result))
>i have added the parenthesis around
>$offset + (int)$displayItemLimit
>so that the addition get's completed before the > operator is evaluated.
>
>let me know if that fixes the problem
>
>
I'm sorry I'm a bit confused as to where you pulled that information
from. Here is the snippet now that correctly produces the "next" link:
// NEXT LINK
$pageItemCount = (int)(@sizeof($this->result) - ($page *
$displayItemLimit));
if ($page <= $numPages && (int)$pageItemCount > 0) {
$pageNext = $page + 1;
$html .= "<b>|</b> <a
href=\"index.php?$qs&page=$pageNext\">Next ";
$html .= ($pageItemCount < $displayItemLimit) ? $pageItemCount
: $displayItemLimit;
$html .= " ${section}s in \"$album\"</a>";
}
They need to make pagination easy.
Phil
>Joe Crawford Jr.
>
>
>----- Original Message -----
>From: "Phillip Powell" <phillip.powell at adnet-sys.com>
>To: "NYPHP Talk" <talk at lists.nyphp.org>
>Sent: Thursday, June 03, 2004 1:45 PM
>Subject: [nycphp-talk] Problem with Pagination
>
>
>
>
>>I wrote a class method that will handle pagination regarding
>>medium-sized resultsets (estimating maximum number of rows at 500).
>>Everything works beautifully, except one annoying problem that involves
>>someone with a math degree or really really good with numbers:
>>
>>The "next link" displays the wrong number of "next" items every time! I
>>can't honestly, for the life of me, figure out the algorithm to get it
>>right. The pagination functionality works perfectly, except that one
>>
>>
>part.
>
>
>>Here is the "Reader's Digest" version of my class:
>>
>>[PHP]
>>|class PaginationView extends View {
>>
>> var $result; // YOUR RESULTSET
>>
>> function PaginationView($result) { // CONSTRUCTOR
>> $this->result = $result;
>> }
>>
>> function &displayPage() { // STATIC HTML
>>STRING METHOD
>> global $section, $action, $album, $headerMenuArray, $willPaginate,
>>
>>
>$displayItemLimit;
>
>
>> foreach ($_REQUEST as $key => $val) if (!isset(${$key})) ${$key} =
>>
>>
>$val;
>
>
>> $qs =
>>
>>
>"section=$section&action=$action&sort=$sort&chooseAlbum=1&album=" .
>urlencode($album) . '&willKeepPageSession=1'; //
>
>
>>FOR EASE OF WRITE
>>
>> if ((int)$page === 0) $page = 1;
>> $page = (int)$page; // CONVERT TO INTEGER
>>
>> if (@sizeof($this->result) > $displayItemLimit &&
>>
>>
>$willPaginate) {
>
>
>> $html .= "<div align=\"center\">\n";
>>
>> // PREVIOUS LINK
>> if ((int)$page !== 1) {
>> $pagePrev = $page - 1;
>> $html .= " <a href=\"index.php?$qs&page=$pagePrev\">Previous
>>
>>
>$displayItemLimit ${section}s in \"$album\"</a> <b>|</b> ";
>
>
>> }
>>
>> $numPages = (int)(@sizeof($this->result) /
>>
>>
>$displayItemLimit);
>
>
>> // ALL PAGES (PAGE NUMBER) LINK(S) EXCEPT FOR LAST PAGE
>> for ($i = 1; $i <= $numPages; $i++) {
>> if ((int)$i === (int)$page) $html .= "$i <b>|</b> ";
>>
>>
>else $html .= "<a
>href=\"index.php?$qs&page=$i\">$i</a> <b>|</b> ";
>
>
>> }
>>
>> // LAST PAGE NUMBER LINK
>> if (@sizeof($this->result) % $displayItemLimit != 0) {
>> if ((int)$i === (int)$page) $html .= "$i "; else $html .=
>>
>>
>"<a href=\"index.php?$qs&page=$i\">$i</a> ";
>
>
>> }
>>
>> // NEXT LINK
>> $offset = (int)(@sizeof($this->result) - ($displayItemLimit *
>>
>>
>($page - 1)));
>
>
>> if ($offset > 0) {
>> $pageNext = $page + 1;
>> $html .= " <b>|</b> <a
>>
>>
>href=\"index.php?$qs&page=$pageNext\">Next ";
>
>
>> $html .= ($offset + (int)$displayItemLimit >
>>
>>
>@sizeof($this->result)) ? (int)($displayItemLimit - $offset) :
>$displayItemLimit;
>
>
>> $html .= " ${section}s in \"$album\"</a>";
>> }
>>
>> $html .= "\n</div>\n";
>> }
>> return $html;
>> }
>>
>>}
>>
>>|
>>
>>--
>>[/PHP]
>>Here is a sample output that results with a $displayItemLimit of
>>20 items and I'm on page "1" and there are 45 items altogether:
>>
>>
>>
>>
>>
>> quote:
>> ----------------------------------------------------------------------
>>
>>
>--
>
>
>> 1 | 2 | 3 | Next -25 images in "Album 1"
>> ----------------------------------------------------------------------
>>
>>
>--
>
>
>>
>>
>>
>>The problem is the $offset variable I know in the // NEXT LINK code
>>block, but I'm stuck, I can't figure it out, furthermore, both of these
>>utterly fail in PHP 4.3.2 on my system:
>>
>>
>>
>>
>>
>> |PHP:|
>> ----------------------------------------------------------------------
>>
>>
>--
>
>
>> |
>> $pagePrev = $page--;
>> |
>> ----------------------------------------------------------------------
>>
>>
>--
>
>
>> |PHP:|
>> ----------------------------------------------------------------------
>>
>>
>--
>
>
>> |
>> $pageNext = $page++;
>> |
>> ----------------------------------------------------------------------
>>
>>
>--
>
>
>>
>>Both result in $pagePrev and $pageNext having null values even though
>>$page exists and is cast into an integer
>>
>>-----------------------
>>
>>At this point I'm not sure what else to do since I'm close to implementing
>>
>>
>my Pagination class instantiation on my other display classes, but not until
>I get this one problem fixed or someone just guide me in the right direction
>as to the exactly working algorithm for at least the "next" links to display
>correctly.
>
>
>>
>>
>>*Update*
>>
>>I am basing my algorithm on the tutorial at
>>http://www.phpfreaks.com/tutorials/43/4.php
>>
>>Thanx
>>Phil
>>--------------------------------------------------------------------------
>>
>>
>-------
>
>
>>Phil Powell
>>Multimedia Programmer
>>BPX Technologies, Inc.
>>#: (703) 709-7218 x107
>>Fax: (703) 709-7219
>>
>>
>>
>>_______________________________________________
>>talk mailing list
>>talk at lists.nyphp.org
>>http://lists.nyphp.org/mailman/listinfo/talk
>>
>>
>>
>>
>
>_______________________________________________
>talk mailing list
>talk at lists.nyphp.org
>http://lists.nyphp.org/mailman/listinfo/talk
>
>
>
--
---------------------------------------------------------------------------------
Phil Powell
Multimedia Programmer
BPX Technologies, Inc.
#: (703) 709-7218 x107
Fax: (703) 709-7219
More information about the talk
mailing list