public function writeToCell($rowIndex,
                                $columnIndex,
                                $text,
                                PHPRtfLite_Font $font = null,
                                PHPRtfLite_ParFormat $parFormat = null,
                                $convertTagsToRtf = true)
    {
        $cell = $this->getCell($rowIndex, $columnIndex);
        if ($font === null) {
            $font = $cell->getFont();
        }
        return $cell->writeText($text, $font, $parFormat, $convertTagsToRtf);
    }