Announcement Scheduler #

A Flutter package for scheduling announcements with support for one-time, recurring notifications and text-to-speech.

Features #

• 📅 Flexible Scheduling: Schedule announcements for specific times or recurring patterns
• 🔄 Recurring Patterns: Daily, weekdays, weekends, or custom day selections
• 🔊 Text-to-Speech: Built-in TTS support with configurable voice settings
• 📱 Single-Platform: Currently only Android support.
• ⚙️ Configurable: Extensive configuration options for notifications and TTS
• 🛡️ Validation: Built-in validation to prevent excessive notifications
• 🌍 Timezone Support: Timezone-aware scheduling with optional forced timezones

Installation #

Add this package to your pubspec.yaml:

dependencies:
  announcement_scheduler: ^1.0.2

Then run:

flutter pub get

Quick Start #

The recommended way to use this package is by creating a dedicated service to manage initialization and scheduling. This ensures proper handling of permissions and configuration.

1. Initialize in Main #

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  
  try {
    // Initialize the service
    final service = await AnnouncementService.create(
      // See AnnouncementConfig below for configuration options
      config: AnnouncementConfig(   
        notificationConfig: NotificationConfig(
          channelId: 'daily_reminders',
          channelName: 'Daily Reminders',
          channelDescription: 'Daily motivational announcements',
        ),
      ),
    );

    // Schedule announcements using your service methods
    await service.scheduleWeekly(
      content: 'Time for your workout!',
      announcementTime: TimeOfDay(hour: 7, minute: 0),
      daysOfWeek: [1, 3, 5], // Monday, Wednesday, Friday
    );
    
  } catch (e) {
    print('Failed to initialize: $e');
  }

  runApp(MyApp());
}

Configuration #

AnnouncementConfig #

Configure the scheduler's behavior:

final config = AnnouncementConfig(
  enableTTS: true,
  ttsRate: 0.5,          // Speech rate (0.0 to 1.0)
  ttsPitch: 1.0,         // Speech pitch (0.5 to 2.0) 
  ttsVolume: 1.0,        // Speech volume (0.0 to 1.0)
  ttsLanguage: 'en-US',  // TTS language
  forceTimezone: true,
  timezoneLocation: 'UTC',  // Important to update this to device/user timezone, otherwise notifications will default to show at UTC time
  notificationConfig: NotificationConfig(
    channelId: 'announcements',
    channelName: 'Announcements',
    channelDescription: 'Scheduled announcements',
    importance: Importance.high,
    enableLights: true,
    enableVibration: true,
  ),
  validationConfig: ValidationConfig(
    maxNotificationsPerDay: 10,
    maxScheduledNotifications: 50,
    enableEdgeCaseValidation: true,
  ),
);

Recurrence Patterns #

Support for various recurring patterns:

// Once off
await service.scheduleOnceOff(
  content: 'One-time reminder!',
  dateTime: DateTime.now().add(Duration(hours: 2)),
);

// Daily
await service.scheduleDaily(
  content: 'Daily reminder!',
  announcementTime: TimeOfDay(hour: 9, minute: 0),
);  

// Weekly (on specific days)
await service.scheduleWeekly(
  content: 'Weekly reminder!',
  announcementTime: TimeOfDay(hour: 10, minute: 0),
  daysOfWeek: [1, 3, 5], // Monday, Wednesday, Friday
);

### Timezone Configuration

The package supports flexible timezone configuration to ensure announcements
are delivered at the correct local time for your users:

#### Using System Timezone (Default)

By default, the package uses the device's system timezone:

```dart
final scheduler = await AnnouncementScheduler.initialize(
  config: AnnouncementConfig(
    // forceTimezone is false by default, uses system timezone
    notificationConfig: NotificationConfig(...),
  ),
);

Using a Specific Timezone

You can force a specific timezone for consistent scheduling regardless of device location:

final scheduler = await AnnouncementScheduler.initialize(
  config: AnnouncementConfig(
    forceTimezone: true,
    timezoneLocation: 'America/New_York',  // IANA timezone identifier
    notificationConfig: NotificationConfig(...),
  ),
);

Dynamic Timezone Based on User Location

For apps that serve users in different timezones, you can determine the timezone based on the user's selected location:

// Example: Get timezone from user's city selection
String getUserTimezone(String city) {
  final timezoneMap = {
    'New York': 'America/New_York',
    'Los Angeles': 'America/Los_Angeles',
    'London': 'Europe/London',
    'Tokyo': 'Asia/Tokyo',
    'Sydney': 'Australia/Sydney',
  };
  return timezoneMap[city] ?? 'America/New_York';  // Default fallback
}

// Initialize with user's timezone
final userCity = getUserSelectedCity();  // Your app's method
final scheduler = await AnnouncementScheduler.initialize(
  config: AnnouncementConfig(
    forceTimezone: true,
    timezoneLocation: getUserTimezone(userCity),
    notificationConfig: NotificationConfig(...),
  ),
);

Important Notes:

• Use standard IANA timezone identifiers (e.g., 'America/New_York', 'Europe/ London')
• Timezone configuration affects when announcements are delivered, not the content
• The package handles DST (Daylight Saving Time) transitions automatically
• For location-based apps, update the scheduler configuration when the user changes their location

Use Cases #

This package is perfect for:

• Weather Apps: Daily weather announcements
• Fitness Apps: Workout reminders and motivation
• Productivity Apps: Task reminders and time management
• Meditation Apps: Daily mindfulness prompts
• Educational Apps: Study reminders and learning cues
• Health Apps: Medication reminders and wellness tips
• Accessibility: Voice announcements for visually impaired users

Platform Setup #

Android #

Add permissions to android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
<uses-permission android:name="android.permission.SCHEDULE_EXACT_ALARM" />
<uses-permission android:name="android.permission.USE_EXACT_ALARM" />

Add receivers within the <application> tag:

<receiver android:exported="false" android:name="com.dexterous.
flutterlocalnotifications.ScheduledNotificationReceiver" />
<receiver android:exported="false" android:name="com.dexterous.flutterlocalnotifications.ScheduledNotificationBootReceiver">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"/>
        <action android:name="android.intent.action.MY_PACKAGE_REPLACED"/>
        <action android:name="android.intent.action.QUICKBOOT_POWERON" />
        <action android:name="com.htc.intent.action.QUICKBOOT_POWERON"/>
    </intent-filter>
</receiver>

iOS #

No additional setup required. Permissions are requested automatically.

Managing Announcements #

// Get all scheduled announcements
final announcements = await scheduler.getScheduledAnnouncements(); //

// Cancel a specific announcement (using the ID from the scheduled announcement)
if (announcements.isNotEmpty) {
  await scheduler.cancelAnnouncementById(announcements.first.id); // using the first ScheduledAnnouncement's ID, but could be any ID
}

// Cancel all announcements
await scheduler.cancelScheduledAnnouncements();

// Listen to status updates
scheduler.statusStream.listen((status) {
  print('Announcement status: ${status.displayName}');
});

// Dispose when done
await scheduler.dispose();

Error Handling #

The package provides specific exception types:

try {
  await scheduler.scheduleAnnouncement(
    content: 'Test announcement',
    announcementTime: TimeOfDay(hour: 8, minute: 0),
  );
} on ValidationException catch (e) {
  print('Validation error: ${e.message}');
} on NotificationPermissionDeniedException catch (e) {
  print('Permission denied: ${e.message}');
} on NotificationSchedulingException catch (e) {
  print('Scheduling failed: ${e.message}');
} on TTSInitializationException catch (e) {
  print('TTS error: ${e.message}');
}

Contributing #

Contributions are welcome! Please read the contributing guidelines before submitting pull requests.

License #

This project is licensed under the MIT License - see the LICENSE file for details.

Support #

If you have questions or need help, please:

1. Check the documentation
2. Search existing issues
3. Create a new issue if needed

Changelog #

See CHANGELOG.md for a detailed list of changes.