Flutter: A value of type 'DateTime?' can't be assigned to a variable of type 'Da-CodePudding

I have this code to display DatePicker and after which TimePicker will come up and I will retrive all the seleted values and it was working perfectly fine until I migrated to null safety by creating a flutter project and coping all my code to the new project and also and doing a few "pub get, Upgrade"

Below is my code:

  //Select Date and Time Widget
  Future _selectDayAndTimeL(BuildContext context) async {
    DateTime _selectedDay = await showDatePicker(
        context: context,
        initialDate: DateTime.now(),
        firstDate: DateTime(2021),
        lastDate: DateTime(2030),
        builder: (BuildContext context, Widget child) => child);

    TimeOfDay _selectedTime = await showTimePicker(
      context: context,
      initialTime: TimeOfDay.now(),
    );

    if (_selectedDay != null && _selectedTime != null) {
      //a little check
    }
    setState(() {
      selectedDateAndTime = DateTime(
        _selectedDay.year,
        _selectedDay.month,
        _selectedDay.day,
        _selectedTime.hour,
        _selectedTime.minute,
      );
      // _selectedDate = _selectedDay;
    });
    // print('...');
  }

Now I got this error:

A value of type 'DateTime?' can't be assigned to a variable of type 'DateTime'.

A value of type 'TimeOfDay?' can't be assigned to a variable of type 'TimeOfDay'.

Check the image to see... I have gone through the questions I saw on almost same issue but it did not solve my problem

How do i solve this error

CodePudding user response：

showDatePicker returns Future DateTime?:

Future<DateTime?> showDatePicker(...)

So, you need to change the following:

DateTime _selectedDay = await showDatePicker(...)

to:

DateTime? _selectedDay = await showDatePicker(...)

showTimePicker returns Future TimeOfDay?:

Future<TimeOfDay?> showTimePicker(...)

So, change the following:

TimeOfDay _selectedTime = await showTimePicker(...);

to:

TimeOfDay? _selectedTime = await showTimePicker(...);

CodePudding user response：

Either null safe variable like TimeOfDay?, or you can get the value at risk with (await showTimePicker(...))!

Check more for null safety of dart