kartik\grid\ColumnTrait::getPageSummaryCellContent PHP Méthode

    protected function getPageSummaryCellContent()
    {
        if ($this->pageSummary === true || $this->pageSummary instanceof \Closure) {
            $summary = $this->calculateSummary();
            return $this->pageSummary === true ? $summary : call_user_func($this->pageSummary, $summary, $this->_rows, $this);
        }
        if ($this->pageSummary !== false) {
            return $this->pageSummary;
        }
        return null;
    }