header property Null safety

String? header
final

Header of the tooltip. By default, the series name will be displayed in the header.

late TooltipBehavior tooltipBehavior;

void initState() {
  tooltipBehavior = TooltipBehavior(
    enable: true,
    header: 'Default'
  );
  super.initState();
}

Widget build(BuildContext context) {
  return SfCartesianChart(
    tooltipBehavior: tooltipBehavior
  );
}

Implementation

final String? header;