Format numbers in Spark DataGrid

DataGridFormatNumbers.mxml

    <fx:Script><![CDATA[
        import spark.formatters.NumberFormatter;
        var numberFormatter:NumberFormatter = new NumberFormatter();
        private function numberFormat(item:Object, column:GridColumn):String {
            return numberFormatter.format(item [column.dataField]);
        }
        ]]>
    </fx:Script>

    <s:GridColumn dataField="valueNum" headerText="Value" labelFunction="numberFormat">

You normally will have the labelFunction already in a base component.

Another approach - probably simpler - is to use the 'formatter' property of the dataGrid and point it to a spark.formatter