// Run the alter display functions
foreach ($rows as $index => & $row) {
foreach ($row as $selectedField => $value) {
- if (array_key_exists($selectedField, $alterFunctions)) {
+ if (array_key_exists($selectedField, $alterFunctions) && isset($value)) {
$rows[$index][$selectedField] = $this->{$alterFunctions[$selectedField]}($value, $row, $selectedField, $alterMap[$selectedField], $alterSpecs[$selectedField]);
}
}