Override JHtml core function select.radiolist

Question

I want to override the output of the select radiolist. I can hack the core, but I'm not really fond of doing that in relation to updates.

So i checked out a system plugin to override the JHTMLselect class. But I am stuck on how to implement it.

I found this topic: How to override core classes?

But it seems that it's not working properly anymore. Also I can't upload the plugin, I get an error. I have the exact code as the plugin above.

This is my code for the override:

<?php
/**
 * @package     Joomla.Plugin
 * @subpackage  System.Overrides
 *
 * @copyright   Copyright (C) 2012 Don Gilbert. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_BASE') or die;

/**
 * System plugin to override core classes terms.
 *
 * @package     Joomla.Plugin
 * @subpackage  System.Overrides
 * @since       2.5
 */
class PlgSystemOverrides extends JPlugin
{
    /* We do our thing in the __construct method
     * so that our overridden classes will be
     * available everywhere
     */
    public function __construct(&$subject, $config)
    {
        parent::__construct($subject, $config);

        include_once 'config.php';
    }
}

That is my main php file. this is my config file

<?php
/**
 * @package     Joomla.Plugin
 * @subpackage  System.Overrides
 *
 * @copyright   Copyright (C) 2012 Don Gilbert. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */
define('OVERRIDES', dirname(__FILE__).'/overrides');

// Use JLoader to register all the classes you want to override
JLoader::register('JHtmlSelect', OVERRIDES.'/select.php', true);

My select.php file is basiscally the whole select.php file in /libraries/cms/html/select.php with a slight change in the radiolist

Answer 1

I got this working ok with just a little change from what you have above. If you can't install the plugin then maybe your filenames or folders aren't correct. Joomla is very fussy about those!

I put everything into a folder named plg_system_overrides and here are the files:

overrides.xml

<?xml version="1.0" encoding="utf-8"?>
<extension version="3.2" type="plugin" group="system" method="upgrade">
    <name>plg_system_overrides</name>
    <description>Plugin to override html radio select</description>
    <files>
        <filename plugin="overrides">overrides.php</filename>
        <filename>config.php</filename>
        <folder>overrides</folder>
    </files>
</extension>

overrides.php - here I think it's best to use onAfterInitialise, as described in those other answers

<?php
defined('JPATH_BASE') or die;
class PlgSystemOverrides extends JPlugin
{
    public function onAfterInitialise()
    {
        include_once 'config.php';
    }
}

My config.php is just the same as yours, and I copied the joomla libraryselect.php into an overrides folder and made a small change to the html output in the genericlist function which worked ok.

I zipped up the plg_system_overrides folder into plg_system_overrides.zip and installed this. It's worth checking that all the files you expect to see are in the Joomla plugins/system folder after you install your plugin.

Don't forget to enable your plugin via the admin / plugins page!

I tested it by inserting into a random site component layout file

<?php echo JHtml::_('select.genericlist', array('a', 'b', 'c'), 'testselect'); ?>

and I could see the change when I used the browser devtools to inspect the html.

Answer 2

You can override specific methods using JHtml::register().

defined('_JEXEC') or die;

use Joomla\CMS\HTML\HTMLHelper;
use Joomla\CMS\Plugin\CMSPlugin;

class PlgSystemOverrides extends CMSPlugin
{
    public function onAfterInitialise()
    {
        if (!HTMLHelper::isRegistered('select.radiolist'))
        {
            HTMLHelper::register('select.radiolist', array(__CLASS__, 'radiolist'));
        }
    }

    public static function radiolist()
    {
        // Your custom function here.
    }
}