protected function initDropdown($chain)
    {
        $settings = array_merge([
            'fields'      => ['name' => 'name', 'value' => 'id'/*, 'text' => 'description'*/],
            'apiSettings' => array_merge(['url' => $this->getCallbackURL().'&q={query}'], $this->apiConfig),
        ], $this->settings);

        $chain->dropdown($settings);
    }