example

Flutter Workmanager Example

Complete working demo showing all Flutter Workmanager features and task types.

Features Demonstrated

• One-off tasks: Immediate background execution
• Periodic tasks: Scheduled recurring background work
• Processing tasks: Long-running iOS background tasks
• Task constraints: Network, battery, and device state requirements
• Debug notifications: Visual feedback when tasks execute
• Error handling: Proper task success/failure/retry logic
• Platform differences: Android vs iOS background execution

Quick Start

1. Clone and run:

   git clone https://github.com/fluttercommunity/flutter_workmanager.git
   cd flutter_workmanager/example
   flutter run

2. Platform setup:

   • Android: Works immediately ✅
   • iOS: Follow the iOS setup in ios/Runner/AppDelegate.swift and ios/Runner/Info.plist

3. Test background tasks:

   • Tap buttons to schedule different task types
   • Put app in background to see tasks execute
   • Check debug notifications to verify execution

Example Tasks

The demo includes practical examples:

• Simulated API sync: Fetches data and stores locally
• File cleanup: Removes old cached files
• Periodic maintenance: Regular app maintenance tasks
• Long processing: iOS-specific long-running tasks

Key Files

• lib/main.dart - Main app with task scheduling UI
• lib/callback_dispatcher.dart - Background task execution logic
• ios/Runner/AppDelegate.swift - iOS background task registration
• ios/Runner/Info.plist - iOS background modes configuration

Testing Background Tasks

Android:

• Tasks run reliably in background
• Enable debug mode to see notifications
• Use adb shell dumpsys jobscheduler to inspect scheduled tasks

iOS:

• Test on physical device (not simulator)
• Enable Background App Refresh in Settings
• Use Xcode debugger commands to trigger tasks immediately

Documentation

For detailed guides and real-world use cases, visit: docs.page/fluttercommunity/flutter_workmanager →

Web Demo (experimental)

Run flutter run -d chrome (or flutter build web and serve over HTTPS or localhost) to get the web-only demo. It demonstrates the experimental workmanager_web package with a simulated weather watch — no network and no API keys needed:

• Two-way worker messaging — the page and the background worker talk over postMessage (Chat tab). Tap "Watch Cardiff" and the worker streams simulated temperatures, alerting when it drops below the threshold; type any text and it echoes back. Page → worker via sendMessageToWorker(), worker → page via sendToPage() (surfaced on WorkmanagerWeb.workerMessages).
• Background tasks in a Web Worker — register one-off / periodic tasks and watch them execute off the main thread (the UI stays responsive while the task's CPU loop runs). "Run check now" fires a one-off task; a periodic temperature check is registered automatically every 15 minutes. Results appear in the Task log tab.
• Service Worker execution + notifications — install the PWA, allow notifications, close the tab, trigger Periodic Background Sync from DevTools and reopen: the task ran inside the Service Worker (compiled Dart dispatcher) and showed a notification while the tab was closed; the result is replayed from IndexedDB into the event log on the next load.

The demo has a Guide tab that walks through all of this step by step.

The background handler lives in lib/web/background_tasks.dart — a Flutter-free file compiled with plain dart compile js into web/background.dart.js (see tool/build_web_background.sh). Temperatures are simulated so the demo works offline; swap _simulatedTemp() for a real fetch to see the same pattern with live data.

Key Files

• lib/main.dart - Main app with task scheduling UI
• lib/web/ - Web-only demo (Flutter-free dispatcher, worker chat, PWA install glue)
• lib/callback_dispatcher.dart - Background task execution logic
• ios/Runner/AppDelegate.swift - iOS background task registration
• ios/Runner/Info.plist - iOS background modes configuration