private function handleFeaturesSingle($fieldName, $features, $featureKey)
    {
        $fMap    = [
            'readonly' => ['readonly', 'class', 'input_readonly'],
            'disabled' => ['disabled']
        ];
        $aReturn = [];
        if (array_key_exists($featureKey, $features)) {
            if (array_key_exists($fieldName, $features[$featureKey])) {
                $aReturn[$featureKey][$fMap[$featureKey][0]] = $fMap[$featureKey][0];
                if (count($fMap[$featureKey]) > 1) {
                    $aReturn[$featureKey][$fMap[$featureKey][1]] = $fMap[$featureKey][2];
                }
            }
        }
        return $aReturn;
    }