Example of implementation of periodic alarms with Flutter alarm plugin.

periodic_alarms.dart

// Let's say we want to set a periodic alarm for each Monday, Wednesday and Friday at 9:41.
// Run this function on app launch when Alarm.init is done.
// It will make sure your periodic alarms are set for the following week.
Future<void> periodicAlarms() async {
  const nbDays = 7; // Number of following days to potentially set alarm
  const time = TimeOfDay(hour: 9, minute: 41); // Time of the periodic alarm
  const days = [
    DateTime.monday,
    DateTime.wednesday,
    DateTime.friday,
  ]; // Days of the week to set the alarm

  final now = DateTime.now();

  // Loop through the next days
  for (var i = 0; i < nbDays; i++) {
    final dateTime = DateTime(
      now.year,
      now.month,
      now.day,
      time.hour,
      time.minute,
    ).add(Duration(days: i));

    if (days.contains(dateTime.weekday)) {
      final alarmSettings = AlarmSettings(
        id: dateTime.day,
        dateTime: dateTime,
        assetAudioPath: 'assets/your_audio.mp3',
        notificationTitle: 'Alarm ringing !',
        notificationBody: 'Periodic alarm ringing, day ${dateTime.day}.',
      );
      await Alarm.set(
        alarmSettings: alarmSettings,
      ); // If the alarm was already set, it will just override it
    }
  }
}