public function renderDataCell($model, $key, $index)
    {
        if (is_callable($this->value)) {
            $value = call_user_func($this->value, $model, $key, $index);
        } else {
            $value = $this->value;
        }
        if ($this->format !== null) {
            $value = Yii::$app->getFormatter()->format($value, $this->format);
        }
        return Html::tag('td', $value, $this->contentOptions);
    }