BackgroundHandling.dart

Purpose

This file manages background tasks using the workmanager plugin. It schedules, configures, and executes background uploads and notification handling for data collected by the app.

Key Imports

import 'dart:async';
import 'dart:io';
import 'package:path_provider/path_provider.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:workmanager/workmanager.dart';
import 'package:flutter_local_notifications/flutter_local_notifications.dart';

  • workmanager: Schedules background tasks

  • flutter_local_notifications: Manages Android local notifications

  • shared_preferences: Stores the current app language

  • path_provider: Used for file system access

Callback Dispatcher

void callbackDispatcher()

Main entry point for Workmanager to execute background jobs. Inside it:

  • Initializes local notification plugin

  • Creates Android notification channel

  • Reads preferred language from shared preferences

  • Calls checkUploadStatus task handler

final prefs = await SharedPreferences.getInstance();
String languageCode = prefs.getString('languageCode') ?? 'es';

Notification Setup

Creates Android-specific channel for upload notifications:

const AndroidNotificationChannel channel = AndroidNotificationChannel(
  'upload_channel',
  'Data Upload Notifications',
  importance: Importance.high,
);

This ensures the OS can show relevant notifications even when the app is inactive.

Integration with Other Services

This file relies on:

  • NotificationHandler.dart: For managing localized and platform-specific notifications

  • Uploader.dart: To check and perform data uploads

These services are invoked when Workmanager executes the task.

Tasks

switch (task) {
  case 'checkUploadStatus':
    return await checkUploadStatus(flutterLocalNotificationsPlugin, languageCode);
}

The checkUploadStatus function is assumed to check whether data needs to be uploaded, trigger an upload, and notify the user.

Platform Notes

  • Currently Android-only behavior is implemented.

  • iOS implementation would require background fetch via different plugins or native code.

Integration in main.dart

Ensure this is included when initializing the app:

Workmanager().initialize(callbackDispatcher, isInDebugMode: false);