ajax update a div

[eluser]gordon Stewart[/eluser]
Hello, I'm converting an existing site to use Codeigniter.

its going slowly - but getting faster & faster as I get used to CI.

I've just got a few (or 1) problem...

Existing script :-

I'm using Ajax, to auto-load a particular div entry in my HTML..

it basically opens up a php script, Looks through a file, & randomly rotates text from a plain-text file. & displays it on the screen.

QUESTION :- How do we do this in Codeigniter ?

are there any tutorials, that show us how to use divs & auto-reload.

Is it a HELPER or a MODEL ? & how do we auto-load a helper/model ? (Its pretty easy to auto-refresh a CONTROLLER (just refresh the URL..)


Is this possible ?

EDIT: I mean the div area auto-reloads.

Every 40 seconds - The text in that part of the screen changes, as the php script reloads (but the rest of the screen remains static / Does not reload)

[eluser]Mr. Pickle[/eluser]
As far as I can think of you just make the div and let the Ajax script call a certain action within a controller. The fact that it is reloaded every x seconds is just front-end Ajax configuration. Just fix an url like /response/randomtext that answers to Ajax.

[eluser]gordon Stewart[/eluser]
[quote author="Mr. Pickle" date="1273866014"]As far as I can think of you just make the div and let the Ajax script call a certain action within a controller. The fact that it is reloaded every x seconds is just front-end Ajax configuration. Just fix an url like /response/randomtext that answers to Ajax.[/quote]


Thanks - Yes, I'm still a beginner with Ajax (this is/was my first Ajax script.

I've found 1-2 sites that say Ajax needs to be installed in the server - Is that right ?
(I'm just a user, not an admin of the site)


I've found this :- http://www.ibm.com/developerworks/web/li...deigniter/

Lots of code (good) - but also confusing (for 2:45 a.m.).

I'll spend the weekend comparing my existing Ajax with whats on the page & just switch 'onkeyup' with the timeout function.

Should be a good learning curve.....

( I could not find any examples - so far, That just auto-load a php script) - They all use/activate Javascript functions )

off bed soon, i'll come back tomorow & try a few things...

[eluser]Mr. Pickle[/eluser]
Yes you have to include for example jquery in your head section.
You can load this directly from a CDN like:
http://ajax.googleapis.com/ajax/libs/jqu...ery.min.js

And for Ajax, have a look at this crystal clear screencast:
Screencast CodeIngniter Ajax Form

It takes you through the complete process of including jQuery and having a section refreshed without refreshing the page. Your case is slightly different but you should be able to figure it out

Also take a look at the other screencasts if your interested, they are interesting for beginners!

[eluser]gordon Stewart[/eluser]
Hmmmm


Ok, I've fixed other areas & focussing on Ajax now..

Can anyone advise where they put the Ajax php script (that produces the report / output I want displayed)..

Do you put it as a helper / controller / where ?


MY JAVASCRIPT / AJAX (extract)
---------------------------

function Show_Message()
{
// alert ("1 - Your browser does support XMLHTTP!");

xmlhttp=GetXmlHttpObject();
if (xmlhttp==null)
{
alert ("Your browser does not support XMLHTTP!");
return;
}
// alert ("Your browser does support XMLHTTP!");


var url="http://"+document.domain+"/extra/headermessage.php";

xmlhttp.onreadystatechange=stateChanged;
xmlhttp.open("GET",url,true);
xmlhttp.send(null);
setTimeout("Show_Message()",20000);
}

---------------------------

I tried to create an 'extra' directory, But still doesn't work.. - i included it as a helper / controller etc..

RESULT :- The script IS being valled - as I see the words where i want them..

HOWEVER, it is displaying my header template TWICE, (I think it can't find the JS file, so re-displays the header file & then the 2nd time, does find the JS file..)

My directory structure (right now) :-


/home/sites/DOMAIN DIRECTORY/application/controllers
/home/sites/DOMAIN DIRECTORY/js

(when i go http://www.domain.com/js/javafile.js - I can see the javascript file )

Is this correct ?

Once I fix the right directory structure & CI finds myAjax the 1st time, the dupe headers will go away.

Thanks...

[eluser]Mr. Pickle[/eluser]
Where is your code that calls the js file?

Also you should not output directly from your controller. Use a view instead.

For example, the ajax script calls:
[full_domain]/ajaxresponse/message/

So 'ajaxresponse' is your controller and 'message' is the function within that controller.
You can have it supported with post vars or whatever, or even use a model within the controller if necessary. The output to the Ajax script should be handled by a view loaded from the message function.

(of course this is a simplified example)

[eluser]gordon Stewart[/eluser]
The 'header' file is in a view..

it just has this :- header.tpl

[removed][removed]


the /js/ directory is at same level as

/home/sites/server_name/application
/home/sites/server_name/js


Is that right ? (I can see the JS file by going to http://domain.com/js/javafile.js etc )

Ps, I've been advised / told to use CI with Smarty - by website admins - tpl file...


EDIT :- Once i get it "going" - I'll move all output to the views...

(i've spent 99% of my time on this, on debugging CI / Googling, & 1% actual programming)...

[eluser]Mr. Pickle[/eluser]
header.tpl? Do you use Smarty template or different templating system?
By default all CI views are .php extension

[eluser]gordon Stewart[/eluser]
Using CI with Smarty - Smarty templates

Yes, I know CI uses PHP templates...

---

In the controller / welcome.php script, i have :-


#$smarty->assign ("data", $data);
#$this->smarty->assign('data', $data);
$this->smarty_parser->parse("ci:news.tpl", $data);
#$this->load->view('news.tpl', $data);
#$this->smarty_parser->parse("news.tpl", $data);


if the BOTTOM one is un-commented, It displays the template HTML - but no data....
If any of the others are un-commented (& the others commented out) - It displays the template source-code (sometimes with data being sent to remplate)....

(I've got another thread running here)... - Re getting data sent to template...