✨ Android background notification service

lib/main.dart

@@ -2,14 +2,18 @@ import 'dart:ui';
 
 import 'package:firebase_core/firebase_core.dart';
 import 'package:firebase_crashlytics/firebase_crashlytics.dart';
-import 'package:flutter/material.dart';
+import 'package:flutter/material.dart' hide Notification;
 import 'package:flutter_acrylic/flutter_acrylic.dart';
+import 'package:flutter_background_service/flutter_background_service.dart';
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:get/get.dart';
 import 'package:go_router/go_router.dart';
 import 'package:protocol_handler/protocol_handler.dart';
 import 'package:provider/provider.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import 'package:solian/bootstrapper.dart';
 import 'package:solian/firebase_options.dart';
+import 'package:solian/models/notification.dart';
 import 'package:solian/platform.dart';
 import 'package:solian/providers/attachment_uploader.dart';
 import 'package:solian/providers/daily_sign.dart';
@@ -41,6 +45,7 @@ void main() async {
   await Future.wait([
     _initializeFirebase(),
     _initializePlatformComponents(),
+    _initializeBackgroundNotificationService(),
   ]);
 
   GoRouter.optionURLReflectsImperativeAPIs = true;
@@ -64,6 +69,85 @@ Future<void> _initializeFirebase() async {
   };
 }
 
+Future<void> _initializeBackgroundNotificationService() async {
+  final prefs = await SharedPreferences.getInstance();
+  if (prefs.getBool('service_background_notification') != true) return;
+
+  final service = FlutterBackgroundService();
+
+  await service.configure(
+    androidConfiguration: AndroidConfiguration(
+      onStart: onBackgroundNotificationServiceStart,
+      autoStart: true,
+      autoStartOnBoot: true,
+      isForegroundMode: false,
+    ),
+    // This feature won't be able to use on iOS
+    // We got APNs support covered
+    iosConfiguration: IosConfiguration(
+      autoStart: false,
+    ),
+  );
+
+  await service.startService();
+}
+
+@pragma('vm:entry-point')
+void onBackgroundNotificationServiceStart(ServiceInstance service) async {
+  WidgetsFlutterBinding.ensureInitialized();
+  DartPluginRegistrant.ensureInitialized();
+
+  Get.put(AuthProvider());
+  Get.put(WebSocketProvider());
+
+  final auth = Get.find<AuthProvider>();
+  await auth.refreshAuthorizeStatus();
+  await auth.ensureCredentials();
+  if (!auth.isAuthorized.value) {
+    debugPrint(
+      'Background notification do nothing due to user didn\'t sign in.',
+    );
+    return;
+  }
+
+  const notificationChannelId = 'solian_notification_service';
+
+  final FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin =
+      FlutterLocalNotificationsPlugin();
+
+  final ws = Get.find<WebSocketProvider>();
+  await ws.connect();
+  debugPrint('Background notification has been started');
+  ws.stream.stream.listen(
+    (event) {
+      debugPrint(
+        'Background notification service incoming message: ${event.method} ${event.message}',
+      );
+
+      if (event.method == 'notifications.new' && event.payload != null) {
+        final data = Notification.fromJson(event.payload!);
+        debugPrint(
+          'Background notification service got a notification id=${data.id}',
+        );
+        flutterLocalNotificationsPlugin.show(
+          data.id,
+          data.title,
+          [data.subtitle, data.body].where((x) => x != null).join('\n'),
+          const NotificationDetails(
+            android: AndroidNotificationDetails(
+              notificationChannelId,
+              'Solian Notification Service',
+              channelDescription: 'Notifications that sent via Solar Network',
+              importance: Importance.high,
+              icon: 'mipmap/ic_launcher',
+            ),
+          ),
+        );
+      }
+    },
+  );
+}
+
 Future<void> _initializePlatformComponents() async {
   if (!PlatformInfo.isWeb) {
     await protocolHandler.register('solink');
@@ -144,5 +228,7 @@ class SolianApp extends StatelessWidget {
     Get.lazyPut(() => LinkExpandProvider());
     Get.lazyPut(() => DailySignProvider());
     Get.lazyPut(() => LastReadProvider());
+
+    Get.find<WebSocketProvider>().requestPermissions();
   }
 }

lib/providers/websocket.dart

@@ -5,7 +5,9 @@ import 'dart:io';
 
 import 'package:device_info_plus/device_info_plus.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
+import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:get/get.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import 'package:solian/exceptions/request.dart';
 import 'package:solian/models/notification.dart';
 import 'package:solian/models/packet.dart';
@@ -29,20 +31,46 @@ class WebSocketProvider extends GetxController {
 
   @override
   onInit() {
-    FirebaseMessaging.instance
-        .requestPermission(
-            alert: true,
-            announcement: true,
-            carPlay: true,
-            badge: true,
-            sound: true)
-        .then((status) {
-      notifyPrefetch();
-    });
+    notifyPrefetch();
 
     super.onInit();
   }
 
+  void requestPermissions() {
+    try {
+      FirebaseMessaging.instance.requestPermission(
+          alert: true,
+          announcement: true,
+          carPlay: true,
+          badge: true,
+          sound: true);
+    } catch (_) {
+      // When firebase isn't initialized (background service)
+      FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin =
+          FlutterLocalNotificationsPlugin();
+      flutterLocalNotificationsPlugin
+          .resolvePlatformSpecificImplementation<
+              AndroidFlutterLocalNotificationsPlugin>()
+          ?.requestNotificationsPermission();
+      flutterLocalNotificationsPlugin
+          .resolvePlatformSpecificImplementation<
+              IOSFlutterLocalNotificationsPlugin>()
+          ?.requestPermissions(
+            alert: true,
+            badge: true,
+            sound: true,
+          );
+      flutterLocalNotificationsPlugin
+          .resolvePlatformSpecificImplementation<
+              MacOSFlutterLocalNotificationsPlugin>()
+          ?.requestPermissions(
+            alert: true,
+            badge: true,
+            sound: true,
+          );
+    }
+  }
+
   Future<void> connect({noRetry = false}) async {
     if (isConnected.value) {
       return;
@@ -120,6 +148,12 @@ class WebSocketProvider extends GetxController {
   }
 
   Future<void> registerPushNotifications() async {
+    final prefs = await SharedPreferences.getInstance();
+    if (prefs.getBool('service_background_notification') == true) {
+      log('Background notification service has been enabled, skip register push notifications');
+      return;
+    }
+
     final AuthProvider auth = Get.find();
     if (auth.isAuthorized.isFalse) return;
 

lib/screens/settings.dart

@@ -3,6 +3,7 @@ import 'package:get/get.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:solian/exts.dart';
+import 'package:solian/platform.dart';
 import 'package:solian/providers/database/database.dart';
 import 'package:solian/providers/theme_switcher.dart';
 import 'package:solian/router.dart';
@@ -16,7 +17,7 @@ class SettingScreen extends StatefulWidget {
 }
 
 class _SettingScreenState extends State<SettingScreen> {
-  late final SharedPreferences _prefs;
+  SharedPreferences? _prefs;
 
   Widget _buildCaptionHeader(String title) {
     return Container(
@@ -42,7 +43,7 @@ class _SettingScreenState extends State<SettingScreen> {
                 seedColor: color,
               ),
             );
-        _prefs.setInt('global_theme_color', color.value);
+        _prefs?.setInt('global_theme_color', color.value);
         context.clearSnackbar();
         context.showSnackbar('themeColorApplied'.tr);
       },
@@ -62,6 +63,9 @@ class _SettingScreenState extends State<SettingScreen> {
     super.initState();
     SharedPreferences.getInstance().then((inst) {
       _prefs = inst;
+      if (mounted) {
+        setState(() {});
+      }
     });
   }
 
@@ -81,6 +85,35 @@ class _SettingScreenState extends State<SettingScreen> {
                   .toList(),
             ).paddingSymmetric(horizontal: 12, vertical: 8),
           ),
+          _buildCaptionHeader('notification'.tr),
+          Tooltip(
+            message: 'settingsNotificationBgServiceDesc'.tr,
+            child: CheckboxListTile(
+              contentPadding: const EdgeInsets.symmetric(horizontal: 22),
+              secondary: const Icon(Icons.system_security_update_warning),
+              enabled: PlatformInfo.isAndroid,
+              title: Text('settingsNotificationBgService'.tr),
+              subtitle: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Text('holdToSeeDetail'.tr),
+                  Text(
+                    'needRestartToApply'.tr,
+                    style: const TextStyle(fontWeight: FontWeight.bold),
+                  )
+                ],
+              ),
+              value:
+                  _prefs?.getBool('service_background_notification') ?? false,
+              onChanged: (value) {
+                _prefs
+                    ?.setBool('service_background_notification', value ?? false)
+                    .then((_) {
+                  setState(() {});
+                });
+              },
+            ),
+          ),
           _buildCaptionHeader('more'.tr),
           ListTile(
             leading: const Icon(Icons.delete_sweep),