SortableGridView.php
public function renderTableRow($model, $key, $index)
    {
        $cells = [];
        /* @var $column Column */
        foreach ($this->columns as $column) {
            $cells[] = $column->renderDataCell($model, $key, $index);
        }

        if ($this->rowOptions instanceof Closure) {
            $options = call_user_func($this->rowOptions, $model, $key, $index, $this);
        } else {
            $options = $this->rowOptions;
        }

        // $options['id'] = "items[]_{$model->primaryKey}";
        $options['data-key'] = is_array($key) ? json_encode($key) : (string) $key;

        return Html::tag('tr', implode('', $cells), $options);
    }
public function renderTableRow($model, $key, $index)
    {
        $cells = [];
        /* @var $column Column */
        foreach ($this->columns as $column) {
            $cells[] = $column->renderDataCell($model, $key, $index);
        }

        if ($this->rowOptions instanceof Closure) {
            $options = call_user_func($this->rowOptions, $model, $key, $index, $this);
        } else {
            $options = $this->rowOptions;
        }

        // $options['id'] = "items[]_{$model->primaryKey}";
        $options['data-key'] = is_array($key) ? json_encode($key) : (string) $key;

        return Html::tag('tr', implode('', $cells), $options);
    }
{@inheritDoc}
@see \yii\grid\GridView::renderTableRow()