WeightField Field Type

WeightField extends Joomla's ListField to render a <select> populated with every enabled weight class from #__j2commerce_weights. Weight classes define the unit of measurement (kilogram, gram, pound, ounce, etc.) used on product weights. The stored value is the integer primary key j2commerce_weight_id.

Class Reference

Property	Value
Class	WeightField
Namespace	J2Commerce\Component\J2commerce\Administrator\Field
File	administrator/components/com_j2commerce/src/Field/WeightField.php
Extends	Joomla\CMS\Form\Field\ListField
Field type token	Weight
Since	6.0.7

Database Query

SELECT j2commerce_weight_id AS value, weight_title AS text
FROM #__j2commerce_weights
WHERE enabled = 1
ORDER BY weight_title ASC

The stored value is j2commerce_weight_id (integer).

XML Usage

Basic Usage

<field
    name="weight_class_id"
    type="Weight"
    label="COM_MYPLUGIN_FIELD_WEIGHT_LABEL"
    description="COM_MYPLUGIN_FIELD_WEIGHT_DESC"
/>

With Placeholder

<field
    name="weight_class_id"
    type="Weight"
    label="COM_MYPLUGIN_FIELD_WEIGHT_LABEL">
    <option value="0">COM_MYPLUGIN_SELECT_WEIGHT</option>
</field>

Supported XML Attributes

Attribute	Type	Description
name	string	Form field name
label	string	Language key for the field label
description	string	Language key for the tooltip
default	integer	Default selected weight class ID
required	boolean	Whether a value is required
multiple	boolean	Allow multi-select
class	string	Additional CSS classes on the <select> element

Usage in Plugin Forms

Shipping plugins commonly expose a weight class selector so administrators can specify which unit their rates are defined in:

<?xml version="1.0" encoding="utf-8"?>
<form addfieldprefix="J2Commerce\Component\J2commerce\Administrator\Field">

    <fieldset name="basic">

        <field
            name="weight_class_id"
            type="Weight"
            label="COM_MYPLUGIN_FIELD_WEIGHT_LABEL"
            description="COM_MYPLUGIN_FIELD_WEIGHT_DESC"
            default="0">
            <option value="0">COM_MYPLUGIN_SELECT_WEIGHT</option>
        </field>

    </fieldset>

</form>

In a Plugin Manifest <config> Block

<config>
    <fields name="params" addfieldprefix="J2Commerce\Component\J2commerce\Administrator\Field">
        <fieldset name="basic">
            <field
                name="weight_class_id"
                type="Weight"
                label="COM_MYPLUGIN_WEIGHT_CLASS_LABEL"
                description="COM_MYPLUGIN_WEIGHT_CLASS_DESC"
            />
        </fieldset>
    </fields>
</config>

Reading the Value in PHP

$params        = $this->params;
$weightClassId = (int) $params->get('weight_class_id', 0);

// Retrieve the unit abbreviation if needed
$db    = Factory::getContainer()->get(DatabaseInterface::class);
$query = $db->getQuery(true)
    ->select($db->quoteName('weight_unit'))
    ->from($db->quoteName('#__j2commerce_weights'))
    ->where($db->quoteName('j2commerce_weight_id') . ' = :id')
    ->bind(':id', $weightClassId, ParameterType::INTEGER);

$db->setQuery($query);
$unit = $db->loadResult(); // e.g., "kg"

Source Code

// File: administrator/components/com_j2commerce/src/Field/WeightField.php

declare(strict_types=1);

namespace J2Commerce\Component\J2commerce\Administrator\Field;

use Joomla\CMS\Factory;
use Joomla\CMS\Form\Field\ListField;
use Joomla\CMS\HTML\HTMLHelper;
use Joomla\CMS\Language\Text;
use Joomla\Database\DatabaseInterface;

class WeightField extends ListField
{
    protected $type = 'Weight';

    public function getOptions(): array
    {
        $options = parent::getOptions();

        $db    = Factory::getContainer()->get(DatabaseInterface::class);
        $query = $db->getQuery(true)
            ->select([
                $db->quoteName('j2commerce_weight_id', 'value'),
                $db->quoteName('weight_title', 'text')
            ])
            ->from($db->quoteName('#__j2commerce_weights'))
            ->where($db->quoteName('enabled') . ' = 1')
            ->order($db->quoteName('weight_title') . ' ASC');

        $db->setQuery($query);

        foreach ($db->loadObjectList() as $weight) {
            $options[] = HTMLHelper::_('select.option', $weight->value, $weight->text);
        }

        return $options;
    }
}

Notes

• Weight classes are managed under J2Commerce -> Configuration -> Weights.
• Only classes with enabled = 1 appear. The weight_title column stores the human-readable name (e.g., "Kilogram", "Pound").
• The weight_unit abbreviation (e.g., kg, lb) is available in #__j2commerce_weights but not exposed by this field's option label. Query it separately when you need the abbreviation in calculations.
• Pair with LengthField on product shipping forms.

Related

• LengthField — Length class dropdown