Help with notifiers

[llynix]

I've got a simple module that I'd like to release.. but it makes a tiny change in a core file (includes/modules/pages/logoff/header_php.php)

$_SESSION['popup'] = 1;  //Added to keep popup from going off when you logoff.

// This should be last line of the script:
$zco_notifier->notify('NOTIFY_HEADER_END_LOGOFF');
?>

Now I'm fairly sure I can use that notify thing to launch my one line of code but the instructions listed here:
http://www.zen-cart.com/wiki/index.p..._API_Tutorials

Were a little more complicated then what I'm trying to achieve. Can anyone simplify them? Or perhaps point me at a simple module that uses them?

I looked at my own cart in includes/classes/observers and found the directory empty.. so apparently none of the mods I'm using utilize this feature.

Thank you,
Anthony

[DrByte]

What does the module do?

[llynix]

It is a model dialog (aka popup) that is designed to go off only once by setting a session variable. Upon logging off the session is destroyed, causing my popup to go off once again. So I reset the session variable after the session destroy to keep it from appearing.

[llynix]

Well I'm not sure if I got it 100% right but it seems to be working.

I created a new observer class in /includes/classes/observers

<?php
class popup extends base {
  function popup() {
    $this->attach($this, array('NOTIFY_HEADER_END_LOGOFF'));
  }
  function update(&$callingClass, $notifier, $paramsArray) {
    $_SESSION['popup'] = 1;
  }
}
?>

That part I think I understand. Although I'm unsure what the $callingClass could be used for.

Next I created an autoloader to load my class in /includes/auto_loaders/config.popup.php

<?php
$autoLoadConfig[10][] = array('autoType'=>'class',
                              'loadFile'=>'observers/class.popup.php');
$autoLoadConfig[90][] = array('autoType'=>'classInstantiate',
                              'className'=>'popup',
                              'objectName'=>'popup');
?>

I guess what throws me here is the 10 and 90. I suppose these tell zen cart when to load the particular code. I suppose the first line loads the class and then the second line runs the popup() code which hooks it into the notifier.

I guess for my purposes this really doesn't matter? That is to say none of my code conflicts with anything else really so when it loads up doesn't matter, just a matter of loading it.

[lat9]

Another approach you could take, again without modifying core files, is to create a file named header_php_popup.php in the /includes/modules/pages/logoff directory, and include the code there. It will be run after the header_php.php file finishes processing and will provide you the same functionality without the complexity of using a notifier.