Guriddo » Topic: reload grid periodically

reload grid periodically

Guriddo
reload grid periodically

This topic has 7 replies, 3 voices, and was last updated 16 years, 5 months ago by tony.

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June 19, 2008 at 8:56 am #71701

admin
Keymaster

Hello!

I’m trying to figure out how to refresh the grid data periodically? I am using the “xmlstring” option to load my data. In my application I make an ajax call every 15 seconds, and I would like to feed the updated xml information to the grid. Perhaps a call to populate() or addXmlData() would do the trick? I think these are private methods however.

I saw the reloadGrid event listed on the API methods page
(http://trirand.com/jqgrid/docs/apimethods.htm) but I’m not sure if this is applicable to my needs.

Thanks for any information you may have.

Kind regards,

Patrick
Creator

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Viewing 7 replies - 1 through 7 (of 7 total)

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April 14, 2008 at 10:50 am #82083

tony
Keymaster

If you use xmlstring one possible solution is:
Load the grid initially with the xml string data
Then after every 15 sec you can do
…..
$(“#mgrid”).setGridParam({datastr:the_new_string_here}).trigger(“reloadGrid”);
…

April 14, 2008 at 10:59 am #82084

tony
Keymaster

Sorry – there is a missing part here – the working example should be:

$(“#mgrid”).setGridParam({datastr:the_new_string_here, datatype: ‘xmlstring’}).trigger(“reloadGrid”);

This is since after reading the xmlstring the datatype is set to clientSide which should be replaced.

Regards
Tony

April 15, 2008 at 2:38 am #82085

PatrickJCollins
Participant

Hi Tony,

Thank you very much for your reply, it works perfectly… except I notice that the memory utilization climbs steadily when I use this technique. If the user leaves the page open for a couple of hours the browser will eventually consume all system resources. I’m not sure if the problem lurks in jqGrid or jQuery itself.

Has anyone else experienced a similar problem and perhaps found a solution?

Kind regards,

Patrick John Collins

April 15, 2008 at 3:43 am #82087

tony
Keymaster

Not sure that this will help, but if you make a external request with jQuery via ajax and then pass this request to the jqGrid you should terminate the request – i.e if the variable is my_request you shoild make my_request = null. Also this is common technique – if you look in jqGrid code every request after success is terminated.

Regards
Tony

April 15, 2008 at 9:45 am #82096

PatrickJCollins
Participant

Hi Tony

Thank you once again for your response. After some more testing, I must humbly admit that the memory utilization was not in fact increasing. The problem is that there is a bug in Drip, the memory monitor that I was using! When I used the Windows task manager I saw that memory usage was flat.

More on the bug in Drip here :
http://www.dynamicdrive.com/forums/archive/index.php/t-18392.html

Regards,

Patrick Collins

April 16, 2008 at 3:13 am #82103

PatrickJCollins
Participant

Hi Tony,

Continuing on from my original question, do you know if it is possible to preserve the current sort order when reloading the grid?

In other words, once the grid is loaded the user may click on a column header to change the sort order, then a few seconds later when the application refreshes the underlying data, the sort order is lost.

Many thanks!

Patrick Collins

April 16, 2008 at 4:28 am #82104

tony
Keymaster

Hi Patrick,

IMHO You have two possible solutions.
You have a special case here. What is happen?
You have xml string that is loaded into the grid. After that the datatype is set to clientSide automatically from the grid. Between the interval the user click to sort some column. The data is sorted in appropriate way (do not forget to set sorttype in colModel when the data is clientSide). The new sort parameters are saved in the options. There is another request (after some time) that is not sended from the grid. The expected data should be sorted in the new way, but this is not true since this is a request from other place.
So the solutions.

1. You should become the xml string already sorted – you can pass two parameters to the “external” request sortname and sortorder. These can be obtained with getGridParam method. If this is not possible

2. You should make second reloading of the grid to sort the data in appropriate way. This can be easy done with the flowing trick.
Use loadComplete event. In case of xmlstring or jsonstring this callback is executed after the data is loaded. The code should be something like:

$("#mygrid").jqGrid( { ... loadComplete: function () {
if ( the sort order or name is changed ) { $("#mygrid").trigger("reloadGrid"); } }, ... });

Regards
Tony
Author

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