如何与Flutter后台服务配合使用？

Question

您好，我正在尝试创建一个颤振应用程序，即使应用程序关闭也能显示通知。

我设法找到了一些与flutter_background_service相关的插件，但是当我尝试复制示例中显示的代码时，它显示了一些与 AndroidServiceInstance 和 setAsBackgroundService() 相关的错误，说明它们未定义。如何解决这个问题？有没有更好的方法来实现我想要的？谢谢之前。

这是我当前的代码：

Future<void> initializeService() async {
  final service = FlutterBackgroundService();

  const AndroidNotificationChannel channel = AndroidNotificationChannel(
    notificationChannelId, // ID
    'MY FOREGROUND SERVICE', // Title
    description:
    'This channel is used for important notifications.', // Description
    importance: Importance.low, // importance must be at low or higher level
  );

  final FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin = FlutterLocalNotificationsPlugin();

  if (Platform.isIOS) {
    await flutterLocalNotificationsPlugin.initialize(
      const InitializationSettings(
        iOS: IOSInitializationSettings(),
      ),
    );
  }

  await flutterLocalNotificationsPlugin
      .resolvePlatformSpecificImplementation<
      AndroidFlutterLocalNotificationsPlugin>()
      ?.createNotificationChannel(channel);

  await service.configure(
    androidConfiguration: AndroidConfiguration(
      onStart: onStart,
      autoStart: true,
      isForegroundMode: true,

      notificationChannelId: 'my_foreground',
      initialNotificationTitle: 'AWESOME SERVICE',
      initialNotificationContent: 'Initializing',
      foregroundServiceNotificationId: 888,
    ),

    iosConfiguration: IosConfiguration(
      autoStart: true,
      onForeground: onStart,
      onBackground: onIosBackground,
    ),
  );
  service.startService();
}

onStart(ServiceInstance service) async {
  DartPluginRegistrant.ensureInitialized();

  if (service is AndroidServiceInstance) {
    service.on('setAsForeground').listen((event) {
      service.setAsForegroundService();
    });
    service.on('setAsBackground').listen((event) {
      service.setAsBackgroundService();
    });
  }
  service.on('stopService').listen((event) {
    service.stopSelf();
  });
}

Answer 1

我在重新创建示例应用程序后才意识到。

您需要导入另一个依赖项：

import 'package:flutter_background_service_android/flutter_background_service_android.dart';

我遇到了同样的错误AndroidServiceInstance，并且setAsBackgroundService()在添加附加包之前未定义。