I have date field with date range picker:

$col = array();
$col[“title”] = “Date”;
$col[“name”] = “invdate”;
$col[“width”] = “25”;
$col[“formatter”] = “date”; // makes field required???
$col[“formatoptions”] = array(“srcformat”=>’Y-m-d’,”newformat”=>’Y-m-d’);
$col[“editable”] = true; // this column is editable
$col[“sortable”] = true;
$col[“searchoptions”][“opts”] = array(“initialText”=>”Paieškos periodas”);
$col[“editrules”] = array(“required”=>false, “edithidden”=>true);
$cols[] = $col;

When adding new row I got error message when Date field has no value:
Couldn’t execute query. Column ‘invdate’ cannot be null – INSERT INTO invheader (`client_id`,`seller`,`buyer`,`invoice_number`,`invdate`,`due_date`,`amount`,`tax`,`total`,`sell_purch`,`status`,`note`) VALUES (‘1′,”,”,”,NULL,NULL,”,”,”,’ ‘,’ ‘,”)

$col[“formatter”] = “date”;

line makes field required, because if I comment this line, no error message with empty Date field. But no date picker on the field. If I edit row value and delete date from this field, no error message.

How to fix it?