flt_worker 0.1.0-dev

The flt_worker plugin allows you to schedule and execute Dart-written background tasks in a dedicated isolate, by utilizing the WorkManager API on Android, and the BackgroundTasks API on iOS 13, respectively.

example/lib/main.dart

import 'dart:io';

import 'package:flt_worker/flt_worker.dart';
import 'package:flutter/material.dart';

import 'background_tasks_btc_prices.dart';
import 'background_tasks_counter.dart';
import 'btc_prices.dart';
import 'counter.dart';
import 'work_manager_btc_prices.dart';
import 'work_manager_counter.dart';
import 'worker.dart';

void main() {
  runApp(MyApp());
//  initializeWorker(doWork); // Android
//  initializeWorker(handleBGTask); // iOS
  initializeWorker(worker);
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) => MaterialApp(
        home: Scaffold(
          appBar: AppBar(
            title: const Text('Worker Examples'),
          ),
          body: Builder(
            builder: (context) => SingleChildScrollView(
              child: Container(
                padding:
                    const EdgeInsets.symmetric(vertical: 48, horizontal: 32),
                child: DefaultTextStyle(
                  textAlign: TextAlign.center,
                  style: const TextStyle(),
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    crossAxisAlignment: CrossAxisAlignment.stretch,
                    children: <Widget>[
                      const Text(
                        'High level API examples',
                        style: TextStyle(
                          fontSize: 14,
                          color: Colors.black45,
                        ),
                      ),
                      const SizedBox(height: 16),
                      RaisedButton(
                        child: const Text('Counter'),
                        onPressed: () => Navigator.push(
                            context,
                            MaterialPageRoute(
                              builder: (_) => Counter(),
                            )),
                      ),
                      RaisedButton(
                        child: const Text('Bitcoin price polling'),
                        onPressed: () => Navigator.push(
                            context,
                            MaterialPageRoute(
                              builder: (_) => BtcPrices(),
                            )),
                      ),
                      Padding(
                        padding: const EdgeInsets.only(top: 48, bottom: 16),
                        child: const Text(
                          'Low level platform-specific API examples',
                          style: TextStyle(
                            fontSize: 14,
                            color: Colors.black45,
                          ),
                        ),
                      ),
                      ...(Platform.isAndroid
                          ? _workManagerExamples(context)
                          : _bgTasksExamples(context)),
                    ],
                  ),
                ),
              ),
            ),
          ),
        ),
      );
}

List<Widget> _workManagerExamples(BuildContext context) => [
      RaisedButton(
        child: const Text('Counter\n(OneTimeWorkRequest)'),
        onPressed: () => Navigator.push(
            context,
            MaterialPageRoute(
              builder: (_) => WorkManagerCounter(),
            )),
      ),
      RaisedButton(
        child: const Text('Bitcoin price polling\n(PeriodicWorkRequest)'),
        onPressed: () => Navigator.push(
            context,
            MaterialPageRoute(
              builder: (_) => WorkManagerBtcPrices(),
            )),
      ),
    ];

List<Widget> _bgTasksExamples(BuildContext context) => [
      RaisedButton(
        child: const Text('Counter\n(BGProcessingTaskRequest)'),
        onPressed: () {
          Navigator.push(
              context,
              MaterialPageRoute(
                builder: (_) => BackgroundTasksCounter(),
              ));
        },
      ),
      RaisedButton(
        child: const Text('Bitcoin price polling\n(BGAppRefreshTaskRequest)'),
        onPressed: () {
          Navigator.push(
              context,
              MaterialPageRoute(
                builder: (_) => BackgroundTasksBtcPrices(),
              ));
        },
      ),
    ];

/// iOS BGTasks test.
///
/// e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateLaunchForTaskWithIdentifier:@"com.example.btc_prices_task"]
/// e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateLaunchForTaskWithIdentifier:@"com.example.counter_task"]
/// e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateLaunchForTaskWithIdentifier:@"com.example.task1"]
/// e -l objc -- (void)[[BGTaskScheduler sharedScheduler] _simulateLaunchForTaskWithIdentifier:@"dev.example.task2"]
Future<void> testBGTasks() async {
//  bool r = await submitTaskRequest(BGAppRefreshTaskRequest("com.example.task1"));
//  debugPrint('returns $r');
//
//  r = await submitTaskRequest(BGProcessingTaskRequest("dev.example.task2",
//    earliestBeginDate: DateTime.now().add(Duration(seconds: 10)),
//    requiresExternalPower: true,
//  ));
//  debugPrint('returns $r');
}

//Future<void> handleBGTask(Map<String, dynamic> payload) async => Future.delayed(Duration(seconds: 1), () async {
//  debugPrint('--- doing work in flutter, payload=$payload');
//  Map<String, dynamic> input = payload['input'];
//  if (input['name'] == 'task 01') {
//    debugPrint("    args[2] * opts['op2'] = ${input['args'][2] * input['opts']['op2']}");
//  } else if (input['name'] == 'task 02') {
//    debugPrint("    args[1] - args[2] = ${input['args'][1] - input['args'][2]}");
//  }
//});
//
///// Android WorkManager test.
//Future<void> testWorkManager() async {
//   final enqueued = await enqueueWorkRequest(const OneTimeWorkRequest(
//     tags: ['hello', 'work'],
//     initialDelay: Duration(seconds: 10),
//     constraints: WorkConstraints(
//       networkType: NetworkType.notRoaming,
//     ),
//     backoffCriteria: BackoffCriteria(
//       policy: BackoffPolicy.linear,
//       delay: Duration(seconds: 20),
//     ),
//     input: <String, dynamic>{
//       'name': 'task 01',
//       'args': <dynamic>[
//         'opacity',
//         0xFF,
//         0.76,
//       ],
//       'opts': <String, dynamic>{
//         'op': 'minus',
//         'op1': -1,
//         'op2': 9.986312,
//       }
//     },
//   ));
//   debugPrint('--- enqueued: $enqueued');
//}
//
//Future<void> doWork(WorkPayload payload) async => Future.delayed(Duration(seconds: 1), () async {
//   debugPrint('--- doing work in flutter, payload=$payload');
//   Map<String, dynamic> input = payload.input;
//   if (input['name'] == 'task 01') {
//     debugPrint("    args[2] * opts['op2'] = ${input['args'][2] * input['opts']['op2']}");
//     final enqueued = await enqueueWorkRequest(const OneTimeWorkRequest(
//       tags: ['task'],
//       initialDelay: Duration(seconds: 2),
//       input: <String, dynamic>{
//         'name': 'task 02',
//         'args': <dynamic>['opacity', 0xFF, 0.76],
//       },
//     ));
//     debugPrint('    task#02 enqueued: $enqueued');
//   } else if (input['name'] == 'task 02') {
//     debugPrint("    args[1] - args[2] = ${input['args'][1] - input['args'][2]}");
//   }
//});