jQuery Grid Plugin - jqGrid - Topic: How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work Simple:Press Version 5.7.5.3 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15568 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15568 Well, since we can't persuade you to help, I looked at the code again with a fresh mind today, and I figured it out on my own.  ðŸ™‚

The documentation says:

total: the total pages in the query

records: the total records from the query

But this is misleading and incorrect. What is should say is:

total: the total number of pages in the entire data set

records: the total number of records in the entire data set

The phrase "in the query" is very misleading, because with "True Scrolling", you actually query the database for only a small number of rows at a time! So of course the total of the query is not the entire data set.

Rudiger: If you use this corrected code (notice the records element value), it works correctly:

$s = "<?xml version='1.0' encoding='utf-8'?>\n";

$s .= "<rows>\n";

$s .= "   <page>" . $page . "</page>\n";

$s .= "   <total>" . $totalpages . "</total>\n";

$s .= "   <records>" . $totalrows . "</records>\n";

foreach ($rows as $row)

{

$s .= "   <row id="" . $row['id'] . "">\n";

$s .= "      <cell>" . $row['id'] . "</cell>\n";

$s .= "      <cell>" . $row['word'] . "</cell>\n";

$s .= "   </row>\n";

}

$s .= "</rows>\n";

]]> Wed, 10 Mar 2010 01:42:01 +0200 rudiger on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15567 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15567 This looks like a bug.

The behavior for the examples is way different in IE8 (version 8.0.7600.16385) and in Firefox (version 3.6)...

IE8 won't display more than 50,000 (in the 500,000 row example).

]]> Wed, 10 Mar 2010 01:25:55 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15565 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15565 As I stated in my initial post, it sure would be nice if you would actually allow people to read the PHP you are using on your demo page.

Without being able to read the PHP we are left strictly guessing from seemingly incorrect documentation!

]]> Wed, 10 Mar 2010 01:02:39 +0200 rudiger on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15560 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15560

tony said:

Hello,

How many goldstars?Wink

The error is in your php script just replace

$s .= "<rows>n";
$s .= "   <page>" . $page . "</page>n";
$s .= "   <total>" . $totalpages . "</total>n";
$s .= "   <records>" . count ($rows) . "</records>n";

with

$s .= "<rows>n";
$s .= "   <page>" . $page . "</page>n";
$s .= "   <total>" . count ($rows) . "</total>n";
$s .= "   <records>" .$totalpages  . "</records>n";

I'm having the same problem... I tried both XML and JSON responses, and the true scrolling does not work...

I tried this "fix", and although it scrolls, the bottom row of the grid becomes the totalPages (500,000), instead of the count (10,000,000)...

The examples on the site work with the original PHP? Please tell us the way the site examples are working?

]]> Tue, 09 Mar 2010 22:50:54 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15501 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15501 I find now that this is actually not working correctly at all! Apparently there is a bug in jqGrid!

Only the first 400 rows are loaded, and after that jqGrid just stops invoking the PHP file!

I have documented it here with a live example:

/blog/?page_id=393/help/true-scrolling-bug/

Any comments would be appreciated!

]]> Mon, 08 Mar 2010 21:40:37 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15016 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p15016 Ok thanks I'll debug it!

]]> Sat, 20 Feb 2010 17:10:08 +0200 tony on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14981 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14981 Hello,

Look afgain in your php script, maybe you return only 100 from here

No limitations at all

Tony

]]> Sat, 20 Feb 2010 10:07:44 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14907 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14907 One last question:

If I change the index.js rowNum: argument to 1000, the grid only loads the first 1000 rows. Is there something else I need to change to make it support loading 1000 rows at a time, or is it limited to auto-loading only 100?

]]> Wed, 17 Feb 2010 19:31:24 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14904 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14904 Aha!!!! It works!!!!! Thank you so much for spotting that!

I have fixed my sloppy Javascript as well, thanks to you.  : )

gold starImage Enlarger

]]> Wed, 17 Feb 2010 17:33:41 +0200 tony on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14863 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14863 Hello,

How many goldstars?Wink

The error is in your php script just replace

$s .= "<rows>\n";
$s .= "   <page>" . $page . "</page>\n";
$s .= "   <total>" . $totalpages . "</total>\n";
$s .= "   <records>" . count ($rows) . "</records>\n";

with

$s .= "<rows>\n";
$s .= "   <page>" . $page . "</page>\n";
$s .= "   <total>" . count ($rows) . "</total>\n";
$s .= "   <records>" .$totalpages  . "</records>\n";

By the way you have a error in th js

        colModel:
        [
             {name:'id', index:'id', width:50, key:true},
             {name:'word', index:'word', width:300}, <-------- This will not work in IE
        ],

Regards

Tony

]]> Wed, 17 Feb 2010 11:40:40 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14845 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14845 Wow... This forum really screws up pasted code!

So if you want to see the actual code, here is an archive of it - I included a mySQL dump of the actual database being queried as well:

grid_test.zip

The first person to tell me what is wrong with the code gets a gold star.  ðŸ™‚

]]> Tue, 16 Feb 2010 22:23:19 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14841 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14841 LOL... I truly wish I could "look deeper in the demo", but the demo isn't very deep to begin with! You don't allow us to view the PHP file in the demo. And again, the demo doesn't tell exactly which options are required to make it work. Obviously it's not as straight forward as you seem to indicate! 

I just did a small test, and it's still not working. See if you can tell me why:

Here's my index.html:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DT.....t;&gt;
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=iso-8859-1">
<link rel="stylesheet" type="text/css" media="screen" href="css/ui-smoothness/jquery-ui-1.7.2.custom.css" />  <link rel="stylesheet" type="text/css" media="screen" href="css/ui.jqgrid.css" />  <script type="text/javascript" language="javascript" src="javascript/jquery-1.4.1.min.js"></script>  <script type="text/javascript" language="javascript" src="javascript/jquery-ui-1.7.2.custom.min.js"></script>  <script type="text/javascript" language="javascript" src="javascript/i18n/grid.locale-en.js"></script>  <script type="text/javascript" language="javascript" src="javascript/jquery.jqGrid.min.js"></script>  <script type="text/javascript" language="javascript" src="javascript/index.js"></script> </head> <body>  <table id="my_grid"></table>  <div id="my_grid_pager"></div> </body> </html> 

 Next, here's my index.js file:

jQuery(document).ready(function() {  my_grid = jQuery("#my_grid").jqGrid({  url: 'php/get_grid_data.php',  datatype: 'xml',  mtype: 'POST',  colNames: ['ID', 'Word'],  colModel:  [     {name:'id', index:'id', width:50, key:true},     {name:'word', index:'word', width:300},   ],  scroll: 1,  pager: '#my_grid_pager',  gridview: true,  viewrecords: true,  rowNum: 100,  sortname: 'id',  sortorder: 'asc',  emptyrecords: 'Nothing to display',  caption: 'My Grid',  });  jQuery("#my_grid").navGrid('#my_grid_pager',{edit:false, add:false, del:false, refresh:false}); }); 

Here's my get_grid_data.php file:

<?php

// obtain passed-in parameters
$page = $_POST['page']; $limit = $_POST['rows'];$sortindex = $_POST['sidx']; $sortorder = $_POST['sord']; 

if ($page == 0) $page = 1;
if ($limit == 0) $limit = 1; if ($sortindex == '') $sortindex = 'date'; if ($sortorder == '') $sortorder = 'DESC'; 

$result = db_count_grid_rows ($totalrows);
 
if ($totalrows > 0) {   $totalpages = ceil ($totalrows / $limit);  }  else  {   $totalpages = 0;  }  

if ($page > $totalpages) $page = $totalpages; 
$start = ($limit * $page) - $limit; 
if ($start < 0) $start = 0; 
 $result = db_get_grid_data ($sortindex, $sortorder, $start, $limit, $rows); 

header ("Last-Modified: " . gmdate( "D, d M Y H:i:s" ) . "GMT" );  header ("Cache-Control: no-cache, must-revalidate" );  header ("Pragma: no-cache" ); header ("Content-type: text/xml"); 
$s = "<?xml version='1.0' encoding='utf-8'?>\n"; $s .= "<rows>\n"; $s .= "   <page>" . $page . "</page>\n"; $s .= "   <total>" . $totalpages . "</total>\n"; $s .= "   <records>" . count ($rows) . "</records>\n"; foreach ($rows as $row) {  $s .= "   <row id=\"" . $row['id'] . "\">\n";  $s .= "      <cell>" . $row['id'] . "</cell>\n";  $s .= "      <cell>" . $row['word'] . "</cell>\n";  $s .= "   </row>\n"; } $s .= "</rows>\n";  echo $s;  
// ------------------------------------------------------------------------------------------------ 
function db_count_grid_rows (&$count)  {
global $db_host;  global $db_user;  global $db_pass;  global $db_name; 

$result = true; // default: no error  
$db = mysql_connect ($db_host, $db_user, $db_pass);  if (!$db)   {  $result = mysql_error ();   } 
else
{
if (mysql_select_db ($db_name))   {  $query = "SELECT COUNT(*) AS count FROM my_table";  $db_result = mysql_query ($query);  $row = mysql_fetch_array ($db_result);   $count = $row['count'];  }  else
{ 
$count = 0;  $err = mysql_error();  $result = "mysql_select_db ($db_name) failed: $err";  }  mysql_close ($db);   }  return $result; }  
function db_get_grid_data ($sortindex, $sortorder, $start, $numrows, &$rows)  {
global $db_host;  global $db_user;  global $db_pass;  global $db_name;  
$result = true; // default: rows found  
$db = mysql_connect ($db_host, $db_user, $db_pass);   if (!$db)   {  $result = mysql_error ($db);   }
else
{
if (mysql_select_db ($db_name, $db)) 
{
$sortindex = mysql_real_escape_string ($sortindex);  $sortorder = mysql_real_escape_string ($sortorder);  $start = mysql_real_escape_string ($start);  $numrows = mysql_real_escape_string ($numrows); 
$query = "SELECT * FROM my_table ORDER BY $sortindex $sortorder LIMIT $start , $numrows"; 

$db_result = mysql_query ($query, $db);  if ($db_result !== false)  {  $num = mysql_num_rows ($db_result);  if ($num !== false)  {  while ($row = mysql_fetch_array ($db_result))  {  $rows[] = $row;  }  }  else  {  $err = mysql_error();  if ($err != "")   {   $result = "$err (QUERY = $query)";  }  }  }  else  {  $err = mysql_error ($db);  $result = "mysql_query ($query) failed: $err";  }   }  else  {  $err = mysql_error();  $result = "mysql_select_db ($db_name) failed: $err";  }  mysql_close ($db);   }  return $result; } ?>

When I load the HTML page, the PHP file gets called just once, to load 100 rows starting at row 1. It never gets called again.

So what's wrong or missing here?

]]> Tue, 16 Feb 2010 21:49:36 +0200 tony on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14683 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14683 Hello,

This is right. There should be no change in the server response. Everthing is done client side, the same way as you prepare the paging mechanizm.

Also it seems that your sever response is not correct. There is not somthing special. Just look deeper in the demo.

Best Regards

Tony

]]> Wed, 10 Feb 2010 14:55:30 +0200 monoclast on How does true scrolling work? http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14641 Discussion http://www.trirand.com/blog/?page_id=393/discussion/how-does-true-scrolling-work#p14641 The demonstration page for New in Version 3.6 > True Scrolling Rows doesn't show the bigset.php PHP file, and doesn't indicate which jqGrid options are key to getting real-time scrolling to work correctly.

Also, when I look at the documentation for scrolling options, it isn't clear what is required, which is frustrating, to say the least.

I've added the scroll:1 option to my grid, but apparently that's not enough. I don't see any difference in the parameters jqGrid is passing to my grid url: option PHP script. So obviously I am missing something crucial.

Can someone please list exactly what is required here, and/or update the demo page, and/or update the documentation to show clearly what is required to get real-time "true scrolling" working?

]]> Mon, 08 Feb 2010 22:28:29 +0200