Firebase 推送通知未显示

如何解决Firebase 推送通知未显示

我正在尝试使用 firebase 消息传递和 Flutter 本地通知从 firebase 推送通知，我已将我的项目与 firebase 连接并添加了所需的插件。我可以在我的 firebase 中发布通知，但它们无法出现在应用程序中。 请问如何解决这个问题。

我的代码

main.dart

import 'package:firebase_messaging/firebase_messaging.dart';
import 'package:Flutter/material.dart';
import 'package:Flutter_local_notifications/Flutter_local_notifications.dart';

const AndroidNotificationChannel channel = AndroidNotificationChannel(
    'high_important_channel','High Important Notification','This Channel is used for important notifications',importance: Importance.high,playSound: true);

final FlutterlocalnotificationsPlugin FlutterlocalnotificationsPlugin =
    FlutterlocalnotificationsPlugin();

Future<void> _firebaseMessagingBackgroundHandler(RemoteMessage message) async {
  await Firebase.initializeApp();
  print('A bg message just showed up : ${message.messageId}');
}

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  FirebaseMessaging.onBackgroundMessage(_firebaseMessagingBackgroundHandler);

  await FlutterlocalnotificationsPlugin
      .resolvePlatformSpecificImplementation<
          AndroidFlutterlocalnotificationsPlugin>()
      ?.createNotificationChannel(channel);

  await FirebaseMessaging.instance.setForegroundNotificationPresentationoptions(
      alert: true,badge: true,sound: true);
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',theme: ThemeData(
        primarySwatch: Colors.blue,),home: MyHomePage(title: 'Flutter Demo Home Page'),);
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key,this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  @override
  void initState() {
    super.initState();
    FirebaseMessaging.onMessage.listen((RemoteMessage message) {
      RemoteNotification notification = message.notification;
      AndroidNotification android = message.notification?.android;

      if (notification != null && android != null) {
        FlutterlocalnotificationsPlugin.show(
            notification.hashCode,notification.title,notification.body,NotificationDetails(
                android: AndroidNotificationDetails(
                    channel.id,channel.name,channel.description,color: Colors.blue,playSound: true,icon: '@mipmap/ic_launcher')));
      }
    });

    FirebaseMessaging.onMessageOpenedApp.listen((RemoteMessage message) {
      print('A new onMessageOpenedApp was published!');
      RemoteNotification notification = message.notification;
      AndroidNotification android = message.notification?.android;

      if (notification != null && android != null) {
        showDialog(
            context: context,builder: (_) {
              return AlertDialog(
                title: Text(notification.title),content: SingleChildScrollView(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,children: [Text(notification.body)],);
            });
      }
    });
  }

  void showNotification() {
    setState(() {
      _counter++;
    });
    FlutterlocalnotificationsPlugin.show(
        0,'Testing $_counter','Meeting tomorrow 8:30',NotificationDetails(
          android: AndroidNotificationDetails(
              channel.id,icon: '@mipmap/ic_launcher'),));
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,children: <Widget>[
            Text(
              'You have pushed the button this many times:',Text(
              '$_counter',style: Theme.of(context).textTheme.headline4,],floatingActionButton: FloatingActionButton(
        onpressed: showNotification,tooltip: 'Increment',child: Icon(Icons.add),// This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

build.gradle

def localPropertiesFile = rootProject.file('local.properties')
if (localPropertiesFile.exists()) {
    localPropertiesFile.withReader('UTF-8') { reader ->
        localProperties.load(reader)
    }
}

def FlutterRoot = localProperties.getProperty('Flutter.sdk')
if (FlutterRoot == null) {
    throw new GradleException("Flutter SDK not found. Define location with Flutter.sdk in the local.properties file.")
}

def FlutterVersionCode = localProperties.getProperty('Flutter.versionCode')
if (FlutterVersionCode == null) {
    FlutterVersionCode = '1'
}

def FlutterVersionName = localProperties.getProperty('Flutter.versionName')
if (FlutterVersionName == null) {
    FlutterVersionName = '1.0'
}

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'com.google.gms.google-services'
apply from: "$FlutterRoot/packages/Flutter_tools/gradle/Flutter.gradle"

android {
    compileSdkVersion 30

    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }

    defaultConfig {
        // Todo: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.example.notification"
        minSdkVersion 16
        targetSdkVersion 30
        versionCode FlutterVersionCode.toInteger()
        versionName FlutterVersionName
    }

    buildTypes {
        release {
            // Todo: Add your own signing config for the release build.
            // Signing with the debug keys for Now,so `Flutter run --release` works.
            signingConfig signingConfigs.debug
        }
    }
}

Flutter {
    source '../..'
}

dependencies {
    implementation 'com.google.firebase:firebase-analytics'
    implementation platform('com.google.firebase:firebase-bom:28.2.0')
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
}