public function visualBoolean($value)
    {
        if ($value === true) {
            //return '<i>O</i>';
            return \MUtil_Html::create()->i(['class' => 'fa fa-check', 'style' => 'color: green;']);
        }
        return \MUtil_Html::create()->i(['class' => 'fa fa-times', 'style' => 'color: red;']);
    }