How do I use the SelectableDayPredicate to limit my DatePicker to only weekdays?

Question

I have implemented a DatePicker to my Flutter application. I am trying to limit the picker to only allow the users to choose weekdays. However, I am not sure how to do this. I believe it has got to do with the SelectableDayPredicate. Below is a snippet of my code:

Future<Null> _selectDate(BuildContext context) async {
  final DateTime picked = await showDatePicker(
    context: context,
    initialDate: _date,
    firstDate: new DateTime(DateTime.now().year),
    lastDate: new DateTime(DateTime.now().year+1),
    // to do: I am pretty sure the SelectableDayPredicate should go somewhere here.
  );

  if (picked != null && picked != _date) {
    setState(() {
      _date = picked;
    });
  }
}

The _selectDate function is called when the user taps on the listTile.

Cyperaceous

Answer 1

Here is an example where I omit Fridays and Saturdays from the picker, you can follow the logic here to achieve what you want:

selectableDayPredicate: (DateTime val) =>
            val.weekday == 5 || val.weekday == 6 ? false : true,

Countryside

When I click on the date that on weekend that added into controller selectedDates first time after that disable date how I can achieve that first time click not able to selected? – Shipwreck

This selectableDayPredicate is not available in the DateRangePicker. What can be the possible solution for it, so that I can enable or disable past or future dates? Please help me. – Dowski

Answer 2

Thanks!

However, for date picker you must provide an initialValue which probably should be 'today', but if 'today' is a weekend, then you will get exception!

So iv'e set the initial to 1'st day of month on this case

    initialDate: _dateTime.weekday == 5 || _dateTime.weekday == 6 ? DateTime(DateTime.now().year, DateTime.now().month, 1) :  _dateTime ,
    selectableDayPredicate: (DateTime val) =>
    val.weekday == 5 || val.weekday == 6 ? false : true,

Polycythemia

Answer 3

I got the reference from different answers and handled the date selection of weekdays only, using the following code:

extension DateTimeExtension on DateTime {
  DateTime next(int day) {
    return this.add(
        Duration(days: (day - this.weekday) % DateTime.daysPerWeek,),
    );
  }
}

After this, set the 'initialDate' and 'selectableDayPredicate' as per below:

initialDate: ((DateTime.now().weekday == DateTime.saturday) || (DateTime.now().weekday == DateTime.sunday)) ? DateTime.now().next(DateTime.monday) : DateTime.now(),

selectableDayPredicate: (DateTime val) => val.weekday == DateTime.saturday || val.weekday == DateTime.sunday ? false : true,

My Reference:

1. As per @Moti_Bartov
2. As per @davideliseo

Tapster