onSelectionChanged property Null safety

DateRangePickerSelectionChangedCallback? onSelectionChanged

Called when the new dates or date ranges selected.

The dates or ranges that selected when the selection changes available in the DateRangePickerSelectionChangedArgs.

See also:

class MyAppState extends State<MyApp> {

 void _onSelectionChanged(DateRangePickerSelectionChangedArgs args) {
   if (args.value is PickerDateRange) {
     final DateTime rangeStartDate = args.value.startDate;
     final DateTime rangeEndDate = args.value.endDate;
   } else if (args.value is DateTime) {
     final DateTime selectedDate = args.value;
   } else if (args.value is List<DateTime>) {
     final List<DateTime> selectedDates = args.value;
   } else {
     final List<PickerDateRange> selectedRanges = args.value;

 Widget build(BuildContext context) {
   return MaterialApp(
       home: Scaffold(
     appBar: AppBar(
       title: Text('DatePicker demo'),
     body: SfDateRangePicker(
       onSelectionChanged: _onSelectionChanged,
       selectionMode: DateRangePickerSelectionMode.range,
       initialSelectedRange: PickerDateRange(
           DateTime.now().subtract(Duration(days: 4)),
           DateTime.now().add(Duration(days: 3))),


final DateRangePickerSelectionChangedCallback? onSelectionChanged;