Categories, Custom Fields and Workflow Integration

<?php

/**
 * @package     Tallpine.Administrator
 * @subpackage  com_tallpine
 *
 * @copyright   (C) 2026 Tallpine Hiking Club
 * @license     GNU General Public License version 2 or later
 */

\defined('_JEXEC') or die;

use Joomla\CMS\Association\AssociationExtensionInterface;
use Joomla\CMS\Categories\CategoryFactoryInterface;
use Joomla\CMS\Component\Router\RouterFactoryInterface;
use Joomla\CMS\Dispatcher\ComponentDispatcherFactoryInterface;
use Joomla\CMS\Extension\ComponentInterface;
use Joomla\CMS\Extension\Service\Provider\CategoryFactory;
use Joomla\CMS\Extension\Service\Provider\ComponentDispatcherFactory;
use Joomla\CMS\Extension\Service\Provider\MVCFactory;
use Joomla\CMS\Extension\Service\Provider\RouterFactory;
use Joomla\CMS\HTML\Registry;
use Joomla\CMS\MVC\Factory\MVCFactoryInterface;
use Joomla\Database\DatabaseInterface;
use Joomla\DI\Container;
use Joomla\DI\ServiceProviderInterface;
use Tallpine\Component\Tallpine\Administrator\Extension\TallpineComponent;
use Tallpine\Component\Tallpine\Administrator\Helper\AssociationsHelper;

return new class () implements ServiceProviderInterface {
    public function register(Container $container): void
    {
        $container->set(
            AssociationExtensionInterface::class,
            static fn (Container $container) => new AssociationsHelper($container->get(DatabaseInterface::class))
        );

        $container->registerServiceProvider(new CategoryFactory('\\Tallpine\\Component\\Tallpine'));
        $container->registerServiceProvider(new MVCFactory('\\Tallpine\\Component\\Tallpine'));
        $container->registerServiceProvider(new ComponentDispatcherFactory('\\Tallpine\\Component\\Tallpine'));
        $container->registerServiceProvider(new RouterFactory('\\Tallpine\\Component\\Tallpine'));

        $container->set(
            ComponentInterface::class,
            function (Container $container) {
                $component = new TallpineComponent($container->get(ComponentDispatcherFactoryInterface::class));

                $component->setRegistry($container->get(Registry::class));
                $component->setMVCFactory($container->get(MVCFactoryInterface::class));
                $component->setCategoryFactory($container->get(CategoryFactoryInterface::class));
                $component->setAssociationExtension($container->get(AssociationExtensionInterface::class));
                $component->setRouterFactory($container->get(RouterFactoryInterface::class));

                return $component;
            }
        );
    }
};

<?php

namespace Tallpine\Component\Tallpine\Administrator\Extension;

\defined('_JEXEC') or die;

use Joomla\CMS\Association\AssociationServiceInterface;
use Joomla\CMS\Association\AssociationServiceTrait;
use Joomla\CMS\Categories\CategoryServiceInterface;
use Joomla\CMS\Categories\CategoryServiceTrait;
use Joomla\CMS\Component\Router\RouterServiceInterface;
use Joomla\CMS\Component\Router\RouterServiceTrait;
use Joomla\CMS\Extension\BootableExtensionInterface;
use Joomla\CMS\Extension\MVCComponent;
use Joomla\CMS\Factory;
use Joomla\CMS\Fields\FieldsFormServiceInterface;
use Joomla\CMS\Fields\FieldsServiceTrait;
use Joomla\CMS\HTML\HTMLRegistryAwareTrait;
use Joomla\CMS\Language\Text;
use Joomla\CMS\Tag\TagServiceInterface;
use Joomla\CMS\Tag\TagServiceTrait;
use Joomla\CMS\Workflow\WorkflowServiceInterface;
use Joomla\CMS\Workflow\WorkflowServiceTrait;
use Psr\Container\ContainerInterface;

class TallpineComponent extends MVCComponent implements
    BootableExtensionInterface,
    CategoryServiceInterface,
    FieldsFormServiceInterface,
    AssociationServiceInterface,
    WorkflowServiceInterface,
    RouterServiceInterface,
    TagServiceInterface
{
    use AssociationServiceTrait;
    use HTMLRegistryAwareTrait;
    use RouterServiceTrait;
    use WorkflowServiceTrait;
    use CategoryServiceTrait, TagServiceTrait, FieldsServiceTrait {
        CategoryServiceTrait::getTableNameForSection insteadof TagServiceTrait;
        CategoryServiceTrait::getStateColumnForSection insteadof TagServiceTrait;
        CategoryServiceTrait::prepareForm insteadof FieldsServiceTrait;
    }

    /**
     * Functionality the workflow plugins may take over for this component.
     * Only the published state is workflow-managed; there is no "featured" column.
     */
    protected $supportedFunctionality = [
        'core.state' => true,
    ];

    public function boot(ContainerInterface $container): void
    {
        // Nothing to register yet; HTML helpers would be added here.
    }

    /* ---- Fields ---- */

    public function validateSection($section, $item = null)
    {
        if (Factory::getApplication()->isClient('site')) {
            // The category list view and the front-end edit form use the trail context.
            if ($section === 'category' || $section === 'form') {
                $section = 'trail';
            }
        }

        return $section === 'trail' ? $section : null;
    }

    public function getContexts(): array
    {
        Factory::getApplication()->getLanguage()->load('com_tallpine', JPATH_ADMINISTRATOR);

        return [
            'com_tallpine.trail'      => Text::_('COM_TALLPINE_TRAILS'),
            'com_tallpine.categories' => Text::_('JCATEGORY'),
        ];
    }

    /* ---- Categories and tags: counting items per category and per tag ---- */

    protected function getTableNameForSection(?string $section = null)
    {
        // Without the table prefix: the counting helper adds it.
        return $section === 'category' ? 'categories' : 'tallpine_trails';
    }

    protected function getStateColumnForSection(?string $section = null)
    {
        return 'published';
    }

    /* ---- Workflows ---- */

    public function getWorkflowContexts(): array
    {
        Factory::getApplication()->getLanguage()->load('com_tallpine', JPATH_ADMINISTRATOR);

        return [
            'com_tallpine.trail' => Text::_('COM_TALLPINE_TRAILS'),
        ];
    }

    public function getCategoryWorkflowContext(?string $section = null): string
    {
        return array_key_first($this->getWorkflowContexts());
    }

    public function getWorkflowTableBySection(?string $section = null): string
    {
        return '#__tallpine_trails';
    }

    public function filterTransitions(array $transitions, int $pk): array
    {
        // Keep the transitions that start at the current stage or at "any stage" (-1).
        return array_values(
            array_filter(
                $transitions,
                static fn ($transition) => \in_array((int) ($transition['from_stage_id'] ?? 0), [-1, $pk], true)
            )
        );
    }
}

<!-- com_tallpine.xml (excerpt) -->
<administration>
    <menu img="class:map">COM_TALLPINE</menu>
    <submenu>
        <menu link="option=com_tallpine&amp;view=trails" img="class:map">COM_TALLPINE_TRAILS</menu>
        <menu link="option=com_categories&amp;view=categories&amp;extension=com_tallpine"
              view="categories" img="class:category">COM_TALLPINE_CATEGORIES</menu>
        <menu link="option=com_fields&amp;view=fields&amp;context=com_tallpine.trail"
              img="class:messages-add">COM_TALLPINE_FIELDS</menu>
        <menu link="option=com_fields&amp;view=groups&amp;context=com_tallpine.trail"
              img="class:messages-add">COM_TALLPINE_FIELD_GROUPS</menu>
    </submenu>
    <files folder="admin">
        <filename>access.xml</filename>
        <filename>config.xml</filename>
        <filename>tallpine.xml</filename>
        <folder>forms</folder>
        <folder>services</folder>
        <folder>sql</folder>
        <folder>src</folder>
        <folder>tmpl</folder>
    </files>
</administration>

<?xml version="1.0" encoding="UTF-8"?>
<!-- administrator/components/com_tallpine/forms/trail.xml (excerpt) -->
<form>
    <fieldset name="details" label="COM_TALLPINE_FIELDSET_DETAILS">
        <field name="id" type="number" label="JGLOBAL_FIELD_ID_LABEL" default="0" readonly="true" class="readonly" />

        <field name="title" type="text" label="JGLOBAL_TITLE" required="true" maxlength="255" />

        <field name="alias" type="text" label="JFIELD_ALIAS_LABEL" hint="JFIELD_ALIAS_PLACEHOLDER" />

        <field
            name="catid"
            type="categoryedit"
            label="JCATEGORY"
            extension="com_tallpine"
            addfieldprefix="Joomla\Component\Categories\Administrator\Field"
            required="true"
            default=""
        />

        <field name="published" type="list" label="JSTATUS" default="1" class="form-select-color-state" validate="options">
            <option value="1">JPUBLISHED</option>
            <option value="0">JUNPUBLISHED</option>
            <option value="2">JARCHIVED</option>
            <option value="-2">JTRASHED</option>
        </field>

        <field name="access" type="accesslevel" label="JFIELD_ACCESS_LABEL" validate="options" />

        <field name="language" type="contentlanguage" label="JFIELD_LANGUAGE_LABEL">
            <option value="*">JALL</option>
        </field>

        <field name="tags" type="tag" label="JTAG" class="advancedSelect" multiple="true" />

        <field name="version_note" type="text" label="JGLOBAL_FIELD_VERSION_NOTE_LABEL" maxlength="255" />
    </fieldset>
</form>

<?xml version="1.0" encoding="UTF-8"?>
<access component="com_tallpine">
    <section name="component">
        <action name="core.admin" title="JACTION_ADMIN" />
        <action name="core.manage" title="JACTION_MANAGE" />
        <action name="core.create" title="JACTION_CREATE" />
        <action name="core.edit" title="JACTION_EDIT" />
        <action name="core.edit.state" title="JACTION_EDITSTATE" />
        <action name="core.delete" title="JACTION_DELETE" />
    </section>
    <section name="category">
        <action name="core.create" title="JACTION_CREATE" />
        <action name="core.delete" title="JACTION_DELETE" />
        <action name="core.edit" title="JACTION_EDIT" />
        <action name="core.edit.state" title="JACTION_EDITSTATE" />
    </section>
</access>

<?php

namespace Tallpine\Component\Tallpine\Site\Service;

\defined('_JEXEC') or die;

use Joomla\CMS\Categories\Categories;

/**
 * Category tree of com_tallpine for the site.
 */
class Category extends Categories
{
    public function __construct($options = [])
    {
        $options['table']       = '#__tallpine_trails';
        $options['extension']   = 'com_tallpine';
        $options['accessfield'] = 'access';
        $options['statefield']  = 'published';
        $options['check_dates'] = false;

        parent::__construct($options);
    }
}

<?php

use Joomla\CMS\Factory;

// In a site model or view of com_tallpine.
$component  = Factory::getApplication()->bootComponent('com_tallpine');
$categories = $component->getCategory(['countItems' => 1, 'published' => 1]);

$root     = $categories->get('root');          // CategoryNode of the top of the partition
$alpine   = $categories->get($categoryId);     // one category, or null when not visible
$children = $alpine ? $alpine->getChildren() : [];

foreach ($children as $child) {
    // $child->title, $child->numitems, $child->getPath() ...
}

<?php

\defined('_JEXEC') or die;

use Joomla\CMS\Application\CMSApplicationInterface;
use Joomla\CMS\Installer\InstallerAdapter;
use Joomla\CMS\Installer\InstallerScriptInterface;
use Joomla\CMS\Installer\InstallerScriptTrait;
use Joomla\DI\Container;
use Joomla\DI\ServiceProviderInterface;

return new class () implements ServiceProviderInterface {
    public function register(Container $container): void
    {
        $container->set(
            InstallerScriptInterface::class,
            new class ($container->get(CMSApplicationInterface::class)) implements InstallerScriptInterface {
                use InstallerScriptTrait;

                protected string $extension = 'com_tallpine';

                public function __construct(CMSApplicationInterface $application)
                {
                    $this->setApplication($application);
                }

                public function postflight(string $type, InstallerAdapter $adapter): bool
                {
                    if ($type === 'install') {
                        $this->createDefaultCategory();
                    }

                    return parent::postflight($type, $adapter);
                }

                private function createDefaultCategory(): void
                {
                    $model = $this->getApplication()->bootComponent('com_categories')
                        ->getMVCFactory()
                        ->createModel('Category', 'Administrator', ['ignore_request' => true]);

                    $model->save([
                        'id'          => 0,
                        'parent_id'   => 1,
                        'extension'   => 'com_tallpine',
                        'title'       => 'Uncategorised',
                        'alias'       => 'uncategorised',
                        'published'   => 1,
                        'access'      => 1,
                        'language'    => '*',
                        'description' => '',
                    ]);
                }
            }
        );
    }
};

<?php

namespace Tallpine\Plugin\Content\TallpineConditions\Extension;

\defined('_JEXEC') or die;

use Joomla\CMS\Event\Model\BeforeDeleteEvent;
use Joomla\CMS\Language\Text;
use Joomla\CMS\Plugin\CMSPlugin;
use Joomla\Database\DatabaseAwareTrait;
use Joomla\Database\ParameterType;
use Joomla\Event\SubscriberInterface;

final class TallpineConditions extends CMSPlugin implements SubscriberInterface
{
    use DatabaseAwareTrait;

    public static function getSubscribedEvents(): array
    {
        return ['onContentBeforeDelete' => 'onContentBeforeDelete'];
    }

    public function onContentBeforeDelete(BeforeDeleteEvent $event): void
    {
        $category = $event->getItem();

        if ($event->getContext() !== 'com_categories.category' || $category->extension !== 'com_tallpine') {
            return;
        }

        $db      = $this->getDatabase();
        $id      = (int) $category->id;
        $query   = $db->createQuery()
            ->select('COUNT(*)')
            ->from($db->quoteName('#__tallpine_trails'))
            ->where($db->quoteName('catid') . ' = :catid')
            ->bind(':catid', $id, ParameterType::INTEGER);

        if ((int) $db->setQuery($query)->loadResult() > 0) {
            $this->getApplication()->enqueueMessage(Text::_('PLG_CONTENT_TALLPINECONDITIONS_CATEGORY_NOT_EMPTY'), 'error');
            $event->addResult(false);
        }
    }
}

<!-- administrator/components/com_tallpine/config.xml (excerpt) -->
<config>
    <fieldset name="integration" label="JGLOBAL_INTEGRATION_LABEL">
        <field
            name="custom_fields_enable"
            type="radio"
            label="JGLOBAL_CUSTOM_FIELDS_ENABLE_LABEL"
            layout="joomla.form.field.radio.switcher"
            default="1"
            >
            <option value="0">JNO</option>
            <option value="1">JYES</option>
        </field>
        <field
            name="save_history"
            type="radio"
            label="JGLOBAL_SAVE_HISTORY_OPTIONS_LABEL"
            layout="joomla.form.field.radio.switcher"
            default="0"
            >
            <option value="0">JNO</option>
            <option value="1">JYES</option>
        </field>
        <field
            name="history_limit"
            type="number"
            label="JGLOBAL_HISTORY_LIMIT_OPTIONS_LABEL"
            default="10"
            filter="integer"
            showon="save_history:1"
        />
        <field
            name="workflow_enabled"
            type="radio"
            label="JWORKFLOW_ENABLED_LABEL"
            layout="joomla.form.field.radio.switcher"
            default="0"
            >
            <option value="0">JNO</option>
            <option value="1">JYES</option>
        </field>
    </fieldset>
</config>

<?php
// tmpl/trail/default.php (excerpt)

\defined('_JEXEC') or die;

use Joomla\CMS\Language\Text;
use Joomla\Component\Fields\Administrator\Helper\FieldsHelper;

$fields = FieldsHelper::getFields('com_tallpine.trail', $this->item, true);
?>
<dl class="trail-facts">
    <?php foreach ($fields as $field) : ?>
        <?php if ($field->value === '' || $field->value === null) : ?>
            <?php continue; ?>
        <?php endif; ?>
        <dt><?php echo $this->escape($field->label); ?></dt>
        <dd><?php echo $field->value; ?></dd>
    <?php endforeach; ?>
</dl>

<?php

namespace Tallpine\Component\Tallpine\Administrator\Table;

\defined('_JEXEC') or die;

use Joomla\CMS\Table\Table;
use Joomla\CMS\Tag\TaggableTableInterface;
use Joomla\CMS\Tag\TaggableTableTrait;
use Joomla\CMS\Versioning\VersionableTableInterface;
use Joomla\Database\DatabaseInterface;
use Joomla\Event\DispatcherInterface;

class TrailTable extends Table implements TaggableTableInterface, VersionableTableInterface
{
    use TaggableTableTrait;

    public function __construct(DatabaseInterface $db, ?DispatcherInterface $dispatcher = null)
    {
        // The alias ties the table to its row in #__content_types.
        $this->typeAlias = 'com_tallpine.trail';

        parent::__construct('#__tallpine_trails', 'id', $db, $dispatcher);
    }

    public function getTypeAlias(): string
    {
        return $this->typeAlias;
    }

    // check(), bind() and store() as in the MVC page.
}

-- administrator/components/com_tallpine/sql/install.mysql.utf8.sql (excerpt)
INSERT INTO `#__content_types`
  (`type_title`, `type_alias`, `table`, `rules`, `field_mappings`, `router`, `content_history_options`)
SELECT
  'Tallpine Trail',
  'com_tallpine.trail',
  '{"special":{"dbtable":"#__tallpine_trails","key":"id","type":"TrailTable","prefix":"Tallpine\\\\Component\\\\Tallpine\\\\Administrator\\\\Table\\\\","config":"array()"},"common":{"dbtable":"#__ucm_content","key":"ucm_id","type":"Corecontent","prefix":"Joomla\\\\CMS\\\\Table\\\\","config":"array()"}}',
  '',
  '{"common":{"core_content_item_id":"id","core_title":"title","core_state":"published","core_alias":"alias","core_created_time":"created","core_created_user_id":"created_by","core_ordering":"ordering","core_access":"access","core_language":"language","core_catid":"catid"},"special":{}}',
  '',
  '{"formFile":"administrator\\/components\\/com_tallpine\\/forms\\/trail.xml","hideFields":["asset_id","checked_out","checked_out_time"],"ignoreChanges":["checked_out","checked_out_time","ordering"],"convertToInt":["ordering"],"displayLookup":[{"sourceColumn":"catid","targetTable":"#__categories","targetColumn":"id","displayColumn":"title"},{"sourceColumn":"created_by","targetTable":"#__users","targetColumn":"id","displayColumn":"name"},{"sourceColumn":"access","targetTable":"#__viewlevels","targetColumn":"id","displayColumn":"title"}]}'
WHERE NOT EXISTS (SELECT 1 FROM `#__content_types` WHERE `type_alias` = 'com_tallpine.trail');

-- administrator/components/com_tallpine/sql/uninstall.mysql.utf8.sql (excerpt)
DELETE FROM `#__content_types` WHERE `type_alias` = 'com_tallpine.trail';

<?php
// administrator/components/com_tallpine/src/Controller/TrailController.php (excerpt)

namespace Tallpine\Component\Tallpine\Administrator\Controller;

\defined('_JEXEC') or die;

use Joomla\CMS\MVC\Controller\FormController;
use Joomla\CMS\Versioning\VersionableControllerTrait;

class TrailController extends FormController
{
    use VersionableControllerTrait;

    protected $view_list = 'trails';
}

<?php
// administrator/components/com_tallpine/src/View/Trail/HtmlView.php (excerpt of addToolbar)

use Joomla\CMS\Component\ComponentHelper;

if (!empty($this->item->id)) {
    $toolbar->cancel('trail.cancel');

    if (
        ComponentHelper::isEnabled('com_contenthistory')
        && $this->state->get('params')->get('save_history', 0)
        && $canDo->get('core.edit')
    ) {
        $toolbar->versions('com_tallpine.trail', $this->item->id);
    }
}

<?php

namespace Tallpine\Component\Tallpine\Administrator\Model;

\defined('_JEXEC') or die;

use Joomla\CMS\Factory;
use Joomla\CMS\Form\Form;
use Joomla\CMS\Form\FormFactoryInterface;
use Joomla\CMS\Helper\TagsHelper;
use Joomla\CMS\Language\Associations;
use Joomla\CMS\Language\LanguageHelper;
use Joomla\CMS\MVC\Factory\MVCFactoryInterface;
use Joomla\CMS\MVC\Model\AdminModel;
use Joomla\CMS\MVC\Model\WorkflowBehaviorTrait;
use Joomla\CMS\MVC\Model\WorkflowModelInterface;
use Joomla\CMS\Versioning\VersionableModelInterface;
use Joomla\CMS\Versioning\VersionableModelTrait;

class TrailModel extends AdminModel implements WorkflowModelInterface, VersionableModelInterface
{
    use WorkflowBehaviorTrait;
    use VersionableModelTrait;

    /** Context of the rows in #__associations. */
    protected $associationsContext = 'com_tallpine.item';

    public function __construct($config = [], ?MVCFactoryInterface $factory = null, ?FormFactoryInterface $formFactory = null)
    {
        parent::__construct($config, $factory, $formFactory);

        // Extension and section of the workflow; reads workflow_enabled from the component options.
        $this->setUpWorkflow('com_tallpine.trail');
    }

    public function getForm($data = [], $loadData = true)
    {
        $form = $this->loadForm('com_tallpine.trail', 'trail', ['control' => 'jform', 'load_data' => $loadData]);

        return $form ?: false;
    }

    public function getItem($pk = null)
    {
        $item = parent::getItem($pk);

        if ($item && !empty($item->id)) {
            // Tags are shown in the edit form from the helper.
            $item->tags = new TagsHelper();
            $item->tags->getTagIds($item->id, 'com_tallpine.trail');

            if (Associations::isEnabled()) {
                $item->associations = [];

                foreach (Associations::getAssociations('com_tallpine', '#__tallpine_trails', 'com_tallpine.item', $item->id) as $tag => $association) {
                    $item->associations[$tag] = $association->id;
                }
            }
        }

        return $item;
    }

    protected function preprocessForm(Form $form, $data, $group = 'content')
    {
        if (Associations::isEnabled()) {
            $languages = LanguageHelper::getContentLanguages(false, false, null, 'ordering', 'asc');

            if (\count($languages) > 1) {
                $addForm  = new \SimpleXMLElement('<form />');
                $fields   = $addForm->addChild('fields');
                $fields->addAttribute('name', 'associations');
                $fieldset = $fields->addChild('fieldset');
                $fieldset->addAttribute('name', 'item_associations');

                foreach ($languages as $language) {
                    $field = $fieldset->addChild('field');
                    $field->addAttribute('name', $language->lang_code);
                    $field->addAttribute('type', 'modal_trail');
                    $field->addAttribute('language', $language->lang_code);
                    $field->addAttribute('label', $language->title);
                    $field->addAttribute('translate_label', 'false');
                    $field->addAttribute('select', 'true');
                    $field->addAttribute('new', 'true');
                    $field->addAttribute('edit', 'true');
                    $field->addAttribute('clear', 'true');
                }

                $form->load($addForm, false);
            }
        }

        // Adds the "transition" field (hidden when workflows are off) and imports the workflow plugins.
        $this->workflowPreprocessForm($form, $data);

        parent::preprocessForm($form, $data, $group);
    }

    public function save($data)
    {
        $this->workflowBeforeSave();

        if (parent::save($data)) {
            // A new item always gets its first stage, even when workflows are off,
            // so that switching them on later finds every item in a stage.
            $this->workflowAfterSave($data);

            return true;
        }

        return false;
    }

    public function publish(&$pks, $value = 1)
    {
        $this->workflowBeforeStageChange();

        return parent::publish($pks, $value);
    }

    public function delete(&$pks)
    {
        $result = parent::delete($pks);

        if ($result) {
            $this->workflow->deleteAssociation($pks);
        }

        return $result;
    }

    protected function loadFormData()
    {
        $data = Factory::getApplication()->getUserState('com_tallpine.edit.trail.data', []);

        return $data ?: $this->getItem();
    }
}

-- Optional: a default workflow and stage for com_tallpine.trail (MySQL).
INSERT INTO `#__workflows`
  (`published`, `title`, `description`, `extension`, `default`, `ordering`, `created`, `created_by`, `modified`, `modified_by`)
VALUES
  (1, 'COM_WORKFLOW_BASIC_WORKFLOW', '', 'com_tallpine.trail', 1, 1, CURRENT_TIMESTAMP(), 0, CURRENT_TIMESTAMP(), 0);

INSERT INTO `#__workflow_stages`
  (`ordering`, `workflow_id`, `published`, `title`, `description`, `default`)
SELECT 1, `id`, 1, 'COM_WORKFLOW_BASIC_STAGE', '', 1
FROM `#__workflows`
WHERE `extension` = 'com_tallpine.trail' AND `default` = 1;

<!-- administrator/components/com_tallpine/forms/category.xml -->
<?xml version="1.0" encoding="UTF-8"?>
<form>
    <fields name="params">
        <fieldset name="workflow" label="COM_TALLPINE_WORKFLOW">
            <field
                name="workflow_id"
                type="sql"
                label="COM_TALLPINE_WORKFLOWS"
                class="form-select"
                sql_select="id, title"
                sql_from="#__workflows"
                sql_where="published = 1 AND extension = 'com_tallpine.trail'"
                sql_order="ordering"
                key_field="id"
                value_field="title"
                required="true"
                default="use_default"
                translate="true"
            />
        </fieldset>
    </fields>
</form>