Date Picker

const FDatePicker(
  label: Text('Appointment Date'),
  description: Text('Select a date for your appointment'),
);

const FDatePicker.calendar(
  label: Text('Appointment Date'),
  description: Text('Select a date for your appointment'),
);

FDatePicker.input(
  label: Text('Appointment Date'),
  description: Text('Select a date for your appointment'),
);

class ValidatorDatePickerPage extends StatefulWidget {
  @override
  State<ValidatorDatePickerPage> createState() => _ValidationDatePickerPageState();
}
 
class _ValidationDatePickerPageState extends State<ValidatorDatePickerPage> with SingleTickerProviderStateMixin {
  late final FDatePickerController _controller;
 
  @override
  void initState() {
    super.initState();
    _controller = FDatePickerController(vsync: this, validator: _validate);
  }
 
  String? _validate(DateTime? date) => date?.weekday == 6 || date?.weekday == 7 ? 'Date cannot be a weekend.' : null;
 
  @override
  Widget build(BuildContext context) => FDatePicker(
        controller: _controller,
        label: const Text('Appointment Date'),
      );
 
  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }
}

class FormDatePickerPage extends StatefulWidget {
  @override
  State<FormDatePickerPage> createState() => _FormDatePickerPageState();
}
 
class _FormDatePickerPageState extends State<FormDatePickerPage> with TickerProviderStateMixin {
  final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
  late final FDatePickerController _startDateController;
  late final FDatePickerController _endDateController;
 
  @override
  void initState() {
    super.initState();
    _startDateController = FDatePickerController(
      vsync: this,
      validator: _validateStartDate,
    );
    _endDateController = FDatePickerController(
      vsync: this,
      validator: _validateEndDate,
    );
  }
 
  String? _validateStartDate(DateTime? date) {
    if (date == null) {
      return 'Please select a start date';
    }
    if (date.isBefore(DateTime.now())) {
      return 'Start date must be in the future';
    }
    return null;
  }
 
  String? _validateEndDate(DateTime? date) {
    if (date == null) {
      return 'Please select an end date';
    }
    if (_startDateController.value != null && date.isBefore(_startDateController.value!)) {
      return 'End date must be after start date';
    }
    return null;
  }
 
  @override
  Widget build(BuildContext context) => Padding(
    padding: const EdgeInsets.all(30.0),
    child: Form(
      key: _formKey,
      child: Column(
        children: [
          FDatePicker(
            controller: _startDateController,
            label: const Text('Start Date'),
            description: const Text('Select a start date'),
            autovalidateMode: AutovalidateMode.disabled,
          ),
          const SizedBox(height: 20),
          FDatePicker(
            controller: _endDateController,
            label: const Text('End Date'),
            description: const Text('Select an end date'),
            autovalidateMode: AutovalidateMode.disabled,
          ),
          const SizedBox(height: 25),
          FButton(
            label: const Text('Submit'),
            onPress: () {
              if (_formKey.currentState!.validate()) {
                // Form is valid, process the dates
              }
            },
          ),
        ],
      ),
    ),
  );
 
  @override
  void dispose() {
    _startDateController.dispose();
    _endDateController.dispose();
    super.dispose();
  }
}