Flutter笔记21:showDatePicker和showTimePicker方法

class DatePickerDemo extends StatefulWidget {
  DatePickerDemo({Key key}) : super(key: key);

  @override
  _DatePickerDemoState createState() => _DatePickerDemoState();
}

class _DatePickerDemoState extends State<DatePickerDemo> {
  DateTime _date = DateTime.now();
  TimeOfDay _time = TimeOfDay.now();

  Future<void> _selectDate(BuildContext context) async {
    final DateTime picked = await showDatePicker(
      context: context,
      initialDate: _date,
      //起始时间
      firstDate: DateTime(2020, 1),
      //结束时间
      lastDate: DateTime(2021, 1),
    );
    if (picked != null && picked != _date) {
      setState(() {
        _date = picked;
      });
    }
  }

  Future<void> _selectTime(BuildContext context) async {
    final TimeOfDay picked = await showTimePicker(
      context: context,
      initialTime: _time,
    );
    if (picked != null && picked != _time) {
      setState(() {
        _time = picked;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        children: [
          Text('日期选择'),
          RaisedButton(
            child: Text('选择结果：${_date.toString()}'),
            onPressed: () {
              _selectDate(context);
            },
          ),
          Text('时间选择'),
          RaisedButton(
            child: Text('选择结果：${_time.toString()}'),
            onPressed: () {},
          ),
        ],
      ),
    );
  }
}