Flutter How to set the maximum date range duration in DateTimeRange - flutter

Question

I have the following code with a DateTimeRange and I would like to allow the user to select a range without exceed 15 days. For example a range before today will be 02/02 to 02/16 or lower or after today 02/14 to 03/01 or lower. How can I do that if it's possible ?
class DateRangeView extends StatefulWidget {
late bool isClearClicked;
DateRangeView({Key? key, required this.isClearClicked}) : super(key: key);
#override
DateRangeView createState() => DateRangeViewState();
}
class DateRangeViewState extends State<DateRangeView> {
DateTimeRange? dateRange;
DateTimeRange? initialDateRange;
DateTimeRange? newDateRange;
String getFrom() {
if (dateRange == null) {
return DateTime.now().toRangeDate();
} else {
return dateRange!.start.toRangeDate();
}
}
String getUntil() {
if (dateRange == null) {
return DateTime.now().toRangeDate();
} else {
return dateRange!.end.toRangeDate();
}
}
#override
Widget build(BuildContext context) {
return HeaderWidget(
title: Translation.current.period.toUpperCase(),
child: Row(
children: [
Expanded(
child: ButtonWidget(
text: widget.isClearClicked
? DateTime.now().toRangeDate()
: getFrom(),
onClicked: () => pickDateRange(context),
),
),
Text(Translation.current.untilDateKeyword.toUpperCase(),
style:
TextStyle(fontSize: ThemeSize.text(xl), color: ThemeColor.gray500),
),
Expanded(
child: ButtonWidget(
text: widget.isClearClicked
? DateTime.now().toRangeDate()
: getUntil(),
onClicked: () => pickDateRange(context),
),
),
Icon( Icons.calendar_month_rounded, color: ThemeColor.gray600,),
],
),
);
}
Future pickDateRange(BuildContext context) async {
initialDateRange = DateTimeRange(
start: DateTime.now(),
end: DateTime.now(),
);
newDateRange = await showDateRangePicker(
initialEntryMode: DatePickerEntryMode.calendarOnly,
context: context,
firstDate: DateTime(2022),
lastDate: DateTime(2030),
initialDateRange: dateRange ?? initialDateRange,
builder: (context, Widget? child) => Theme(
data:ThemeData.light().copyWith(
//Header background color
primaryColor: ThemeColor.primaryVariant,
scaffoldBackgroundColor: Colors.grey[50],
dividerColor: Colors.grey,
textTheme: TextTheme(
bodyText2:
TextStyle(color: ThemeColor.gray700, fontSize: ThemeSize.text(xxl)),
),
colorScheme: ColorScheme.fromSwatch().copyWith(
primary: ThemeColor.primaryVariant,
onSurface: Colors.black,
),
),
child: child!,
),
);
if (newDateRange == null) return;
setDateRange();
}
setDateRange() {
setState(() {
dateRange = newDateRange;
widget.isClearClicked = false;
});
Future.delayed(
const Duration(milliseconds: 100), () {
dateRange = initialDateRange;
},
);
}
}

Answer 1

You can use syncfusion_flutter_datepicker library. It has a selectionChanged callback that you can manipulate to limit selectable dates on the go. This is my answer to a similar question
class Home extends StatefulWidget {
const Home({super.key});
#override
State<Home> createState() => _HomeState();
}
class _HomeState extends State<Home> {
final DateTime _minDate = DateTime.now();
DateTime _maxDate = DateTime.now().add(const Duration(days: 365));
final Duration _duration = const Duration(days: 14);
DateTime _start = DateTime.now();
#override
Widget build(BuildContext context) {
return Scaffold(
body: SafeArea(
child: SfDateRangePicker(
minDate: _minDate,
maxDate: _maxDate,
selectionMode: DateRangePickerSelectionMode.range,
onSelectionChanged: (DateRangePickerSelectionChangedArgs args) {
if (args.value is PickerDateRange) {
_start = (args.value as PickerDateRange).startDate!;
setState(() {
// limit the maxDate to 14 days from selected date
_maxDate = _start.add(_duration);
});
}
},
)),
);
}
}

Answer 2

You can change this two params to :
firstDate: DateTime.now(),
lastDate: DateTime.now().add(Duration(days: 15)),