NYCPHP Meetup

[Joe Crawford Jr.]

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

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>&nbsp;<b>|</b>&nbsp;";
>
>          }
>
>              $numPages = (int)(@sizeof($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&nbsp;<b>|</b>&nbsp;";
else $html .= "<a
href=\"index.php?$qs&page=$i\">$i</a>&nbsp;<b>|</b>&nbsp;";
>
>          }
>
>         // LAST PAGE NUMBER LINK
>          if (@sizeof($this->result) % $displayItemLimit != 0) {
>           if ((int)$i === (int)$page) $html .= "$i&nbsp; "; else $html .=
"<a href=\"index.php?$qs&page=$i\">$i</a>&nbsp; ";
>
>          }
>
>         // NEXT LINK
>          $offset = (int)(@sizeof($this->result) - ($displayItemLimit *
($page - 1)));
>
>          if ($offset > 0) {
>           $pageNext = $page + 1;
>           $html .= "&nbsp;<b>|</b>&nbsp;<a
href=\"index.php?$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
>
>