Créer un table_calendar avec sélection de mois et année dans Flutter

dependencies:
  flutter:
    sdk: flutter
  table_calendar: ^3.0.6
  intl: ^0.17.0

Ensuite, exécutez flutter pub get pour installer les dépendances.

import 'package:flutter/material.dart';
import 'package:table_calendar/table_calendar.dart';
import 'package:intl/date_symbol_data_local.dart';
import 'package:intl/intl.dart';

void main() {
  // Initialize les données de localisation de la date
  initializeDateFormatting().then((_) => runApp(MyApp()));
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Calendar Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: CalendarPage(),
    );
  }
}

class CalendarPage extends StatefulWidget {
  @override
  _CalendarPageState createState() => _CalendarPageState();
}

class _CalendarPageState extends State {
  CalendarFormat _calendarFormat = CalendarFormat.month;
  DateTime _focusedDay = DateTime.now();
  DateTime? _selectedDay;
  final DateTime _firstDay = DateTime.utc(2020, 1, 1);
  final DateTime _lastDay = DateTime.utc(2030, 12, 31);

  List _getMonthYearList() {
    List monthYearList = [];
    DateTime date = _firstDay;
    while (date.isBefore(_lastDay)) {
      monthYearList.add(DateFormat.yMMMM('fr_FR').format(date));
      date = DateTime(date.year, date.month + 1, 1);
    }
    monthYearList.add(DateFormat.yMMMM('fr_FR').format(_lastDay));
    return monthYearList;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Table Calendar Example'),
      ),
      body: Column(
        children: [
          _buildCalendarHeader(),
          Expanded(
            child: TableCalendar(
              locale: 'fr_FR',
              firstDay: _firstDay,
              lastDay: _lastDay,
              focusedDay: _focusedDay,
              calendarFormat: _calendarFormat,
              startingDayOfWeek: StartingDayOfWeek.monday,
              selectedDayPredicate: (day) {
                return isSameDay(_selectedDay, day);
              },
              onDaySelected: (selectedDay, focusedDay) {
                setState(() {
                  _selectedDay = selectedDay;
                  _focusedDay = focusedDay;
                });
              },
              onFormatChanged: (format) {
                setState(() {
                  _calendarFormat = format;
                });
              },
              onPageChanged: (focusedDay) {
                _focusedDay = focusedDay;
              },
              availableCalendarFormats: const {
                CalendarFormat.month: 'Month',
                CalendarFormat.week: 'Week',
              },
              calendarStyle: const CalendarStyle(
                todayDecoration: BoxDecoration(
                  color: Colors.orange,
                  shape: BoxShape.circle,
                ),
                selectedDecoration: BoxDecoration(
                  color: Colors.green,
                  shape: BoxShape.circle,
                ),
                weekendTextStyle: TextStyle(color: Colors.red),
                holidayTextStyle: TextStyle(color: Colors.purple),
              ),
              daysOfWeekStyle: const DaysOfWeekStyle(
                weekdayStyle: TextStyle(color: Colors.blue),
                weekendStyle: TextStyle(color: Colors.red),
              ),
              headerVisible: false,
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildCalendarHeader() {
    List monthYearList = _getMonthYearList();
    return Container(
      padding: const EdgeInsets.all(8.0),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: [
          IconButton(
            icon: const Icon(Icons.chevron_left, color: Colors.blue),
            onPressed: () {
              setState(() {
                _focusedDay = DateTime(_focusedDay.year, _focusedDay.month - 1);
              });
            },
          ),
          DropdownButton(
          value: DateFormat.yMMMM('fr_FR').format(_focusedDay),
          items: monthYearList.map((String monthYear) {
            return DropdownMenuItem(
              value: monthYear,
              child: Text(
                monthYear,
                style: const TextStyle(
                  color: Colors.blue, // Couleur du texte
                  fontSize: 16.0,    // Taille de la police
                ),
              ),
            );
          }).toList(),
          onChanged: (String? newMonthYear) {
            if (newMonthYear != null) {
              setState(() {
                DateTime parsedDate = DateFormat.yMMMM('fr_FR').parse(newMonthYear);
                _focusedDay = DateTime(parsedDate.year, parsedDate.month, _focusedDay.day);
              });
            }
          },
          style: const TextStyle(color: Colors.blue),  // Style du texte sélectionné
          icon: const Icon(Icons.arrow_drop_down, color: Colors.blue),  // Icône du bouton déroulant
          underline: const SizedBox(),  // Aucun trait de soulignement (SizedBox avec une taille nulle)
        ),


          IconButton(
            icon: const Icon(Icons.chevron_right, color: Colors.blue),
            onPressed: () {
              setState(() {
                _focusedDay = DateTime(_focusedDay.year, _focusedDay.month + 1);
              });
            },
          ),
        ],
      ),
    );
  }
}

• Utilisez la propriété style pour définir la couleur et la taille du texte dans le DropdownButton.
• Assurez-vous que la couleur du texte reste constante après la sélection.

• Utilisez dropdownColor pour définir la couleur d’arrière-plan des éléments de la liste déroulante.

• Utilisez la propriété icon pour personnaliser l’icône du bouton déroulant.

• Utilisez underline: SizedBox() pour supprimer le trait de soulignement sous le DropdownButton.