protected function encodeColumnFunctions(array $parameters)
{
$columnFunctions = [];
foreach ($parameters['columns'] as $i => $column) {
unset($parameters['columns'][$i]['exportable']);
unset($parameters['columns'][$i]['printable']);
unset($parameters['columns'][$i]['footer']);
if (isset($column['render'])) {
$columnFunctions[$i] = $column['render'];
$parameters['columns'][$i]['render'] = "#column_function.{$i}#";
}
}
return [$columnFunctions, $parameters];
}