Hi,
Updated to 2.6.8 today and found that a bug has occured.
For fields using callbackColumn() and fieldType() at the same time does not seem to work (at least for FIELD_TYPE_DROPDOWN).
$crud->fieldType('compared_to_inv_no_diff', GroceryCrud::FIELD_TYPE_DROPDOWN, [
	1 => "No diff",
	0 => "With diff",
]);
$crud->callbackColumn('compared_to_inv_no_diff', function ($fieldValue, $primaryKeyValue) {
	return $this->__callbackBooleanNull($fieldValue, $primaryKeyValue);
});
protected function __callbackBooleanNull($fieldValue, $primaryKeyValue) {
	if ($fieldValue === null) {
		return "<i class=\"fa fa-question\"></i>";
	} else if ($fieldValue == 0) {
		return "<i class=\"fa fa-exclamation-triangle text-danger\"></i>";
	} else if ($fieldValue == 1) {
		return "<i class=\"fa fa-check text-success\"></i>";
	}
}
Any ideas?
Regards
Jonathan
EDIT: Should add that I'm using GCE with Laravel and MySQL. The field in the database is a nullable boolean field (TINYINT).

 
                                