Добавление select с данными из другой таблицы в modExtra

Extras.window.CreateCategory = function (config) {
    config = config || {};
    if (!config.id) {
        config.id = 'extras-category-window-create';
    }
    Ext.applyIf(config, {
        title: _('extras_category_create'),
        width: 550,
        autoHeight: true,
        url: Extras.config.connector_url,
        action: 'mgr/category/create',
        fields: this.getFields(config),
        keys: [{
            key: Ext.EventObject.ENTER, shift: true, fn: function () {
                this.submit()
            }, scope: this
        }]
    });
    Extras.window.CreateCategory.superclass.constructor.call(this, config);
};
Ext.extend(Extras.window.CreateCategory, MODx.Window, {

    getFields: function (config) {
        return [{
            xtype: 'textfield',
            fieldLabel: _('extras_category_name'),
            name: 'name',
            id: config.id + '-name',
            anchor: '99%',
            allowBlank: false,
        }, {
            xtype: 'textfield',
            fieldLabel: _('extras_category_repository'),
            name: 'repository_id',
            id: config.id + '-repository_id',
            anchor: '99%',
            allowBlank: true,
        }, {
            xtype: 'xcheckbox',
            boxLabel: _('extras_category_active'),
            name: 'active',
            id: config.id + '-active',
            checked: true,
        }];
    },

    loadDropZones: function () {
    }

});
Ext.reg('extras-category-window-create', Extras.window.CreateCategory);


Extras.window.UpdateCategory = function (config) {
    config = config || {};
    if (!config.id) {
        config.id = 'extras-category-window-update';
    }
    Ext.applyIf(config, {
        title: _('extras_category_update'),
        width: 550,
        autoHeight: true,
        url: Extras.config.connector_url,
        action: 'mgr/category/update',
        fields: this.getFields(config),
        keys: [{
            key: Ext.EventObject.ENTER, shift: true, fn: function () {
                this.submit()
            }, scope: this
        }]
    });
    Extras.window.UpdateCategory.superclass.constructor.call(this, config);
};
Ext.extend(Extras.window.UpdateCategory, MODx.Window, {

    getFields: function (config) {
        return [{
            xtype: 'hidden',
            name: 'id',
            id: config.id + '-id',
        }, {
            xtype: 'textfield',
            fieldLabel: _('extras_category_name'),
            name: 'name',
            id: config.id + '-name',
            anchor: '99%',
            allowBlank: false,
        }, {
            xtype: 'textfield',
            fieldLabel: _('extras_category_repository'),
            name: 'repository_id',
            id: config.id + '-repository_id',
            anchor: '99%',
            allowBlank: true,
        }, {
            xtype: 'xcheckbox',
            boxLabel: _('extras_category_active'),
            name: 'active',
            id: config.id + '-active',
        }];
    },

    loadDropZones: function () {
    }

});
Ext.reg('extras-category-window-update', Extras.window.UpdateCategory);

{
            xtype: 'textfield',
            fieldLabel: _('extras_category_repository'),
            name: 'repository_id',
            id: config.id + '-repository_id',
            anchor: '99%',
            allowBlank: true,
        },

<?php

class ExtrasCategoriesGetListProcessor extends modObjectGetListProcessor
{
    public $objectType = 'ExtrasCategories';
    public $classKey = 'ExtrasCategories';
    public $defaultSortField = 'id';
    public $defaultSortDirection = 'DESC';
    //public $permission = 'list';


    /**
     * We do a special check of permissions
     * because our objects is not an instances of modAccessibleObject
     *
     * @return boolean|string
     */
    public function beforeQuery()
    {
        if (!$this->checkPermissions()) {
            return $this->modx->lexicon('access_denied');
        }

        return true;
    }


    /**
     * @param xPDOQuery $c
     *
     * @return xPDOQuery
     */
    public function prepareQueryBeforeCount(xPDOQuery $c)
    {
        $query = trim($this->getProperty('query'));
        if ($query) {
            $c->where([
                'name:LIKE' => "%{$query}%",
                'OR:repository_id:LIKE' => "%{$query}%",
            ]);
        }

        return $c;
    }


    /**
     * @param xPDOObject $object
     *
     * @return array
     */
    public function prepareRow(xPDOObject $object)
    {
		if ($this->getProperty('combo')) {
			$data = array(
				'id' => $object->get('id'),
				'name' => $object->get('name'),
			);
		} else {
			$array = $object->toArray();
			if (!$array['resource']) {
				$array['resource'] = null;
			}

			$array['actions'] = [];

			// Edit
			$array['actions'][] = [
				'cls' => '',
				'icon' => 'icon icon-edit',
				'title' => $this->modx->lexicon('extras_category_update'),
				//'multiple' => $this->modx->lexicon('extras_categories_update'),
				'action' => 'updateCategory',
				'button' => true,
				'menu' => true,
			];

			if (!$array['active']) {
				$array['actions'][] = [
					'cls' => '',
					'icon' => 'icon icon-power-off action-green',
					'title' => $this->modx->lexicon('extras_category_enable'),
					'multiple' => $this->modx->lexicon('extras_categories_enable'),
					'action' => 'enableCategory',
					'button' => true,
					'menu' => true,
				];
			} else {
				$array['actions'][] = [
					'cls' => '',
					'icon' => 'icon icon-power-off action-gray',
					'title' => $this->modx->lexicon('extras_category_disable'),
					'multiple' => $this->modx->lexicon('extras_categories_disable'),
					'action' => 'disableCategory',
					'button' => true,
					'menu' => true,
				];
			}

			// Remove
			$array['actions'][] = [
				'cls' => '',
				'icon' => 'icon icon-trash-o action-red',
				'title' => $this->modx->lexicon('extras_category_remove'),
				'multiple' => $this->modx->lexicon('extras_categories_remove'),
				'action' => 'removeCategory',
				'button' => true,
				'menu' => true,
			];
		}

        return $array;
    }

}

return 'ExtrasCategoriesGetListProcessor';