当应用程序处于前台时，通知消息似乎为空

Question

我已配置 firebase-messaging 和 flutter_local_notifications 以便能够在应用程序处于前台和后台时显示推送通知。但是，当应用程序在前台触发onMessage 时，消息本身似乎是空的。

配置：

FirebaseMessaging fcm = FirebaseMessaging();

flutterLocalNotificationsPlugin =
FlutterLocalNotificationsPlugin();

var initializationSettingsAndroid =
AndroidInitializationSettings('drawable/ic_stat');

var initializationSettingsIOS = IOSInitializationSettings();

var initializationSettings = InitializationSettings(
    initializationSettingsAndroid, initializationSettingsIOS);

flutterLocalNotificationsPlugin.initialize(initializationSettings,
    selectNotification: (String payload) async {});


fcm.configure(
  onLaunch: (Map<String, dynamic> msg) {
    print("On launch $msg");
    showNotification(msg);
  },
  onResume: (Map<String, dynamic> msg) {
    print("On resume $msg");
    showNotification(msg);
  },
  onMessage: (Map<String, dynamic> msg) {
    print("On message $msg");
    showNotification(msg);
  },
);

处理程序：

void showNotification(Map<String, dynamic> msg) async{
  print(msg);
  var notificationsChannel = new AndroidNotificationDetails(
      'my_package',
      'my_organization',
      'notification_channel',
      importance: Importance.Max,
      priority: Priority.High);

  var iOSPlatformChannelSpecifics = new IOSNotificationDetails();

  var platformChannelSpecifics = new NotificationDetails(
      notificationsChannel, iOSPlatformChannelSpecifics);

  await flutterLocalNotificationsPlugin.show(
      0, msg['title'], msg['body'], platformChannelSpecifics,);

  }

应用在前台时登录：

W/FirebaseMessaging(10901): Error while parsing timestamp in GCM event
W/FirebaseMessaging(10901): java.lang.NumberFormatException: null
W/FirebaseMessaging(10901):     at java.lang.Integer.parseInt(Integer.java:483)
W/FirebaseMessaging(10901):     at java.lang.Integer.parseInt(Integer.java:556)
W/FirebaseMessaging(10901):     at com.google.firebase.messaging.zzb.zzc(Unknown Source)
W/FirebaseMessaging(10901):     at com.google.firebase.messaging.zzb.zze(Unknown Source)
W/FirebaseMessaging(10901):     at com.google.firebase.messaging.FirebaseMessagingService.zzd(Unknown Source)
W/FirebaseMessaging(10901):     at com.google.firebase.iid.zzc.run(Unknown Source)
W/FirebaseMessaging(10901):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
W/FirebaseMessaging(10901):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
W/FirebaseMessaging(10901):     at com.google.android.gms.common.util.concurrent.zza.run(Unknown Source)
W/FirebaseMessaging(10901):     at java.lang.Thread.run(Thread.java:761)
W/FirebaseMessaging(10901): Error while parsing timestamp in GCM event
W/FirebaseMessaging(10901): java.lang.NumberFormatException: null
W/FirebaseMessaging(10901):     at java.lang.Integer.parseInt(Integer.java:483)
W/FirebaseMessaging(10901):     at java.lang.Integer.parseInt(Integer.java:556)
W/FirebaseMessaging(10901):     at com.google.firebase.messaging.zzb.zzc(Unknown Source)
W/FirebaseMessaging(10901):     at com.google.firebase.messaging.zzb.zzh(Unknown Source)
W/FirebaseMessaging(10901):     at com.google.firebase.messaging.FirebaseMessagingService.zzd(Unknown Source)
W/FirebaseMessaging(10901):     at com.google.firebase.iid.zzc.run(Unknown Source)
W/FirebaseMessaging(10901):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
W/FirebaseMessaging(10901):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
W/FirebaseMessaging(10901):     at com.google.android.gms.common.util.concurrent.zza.run(Unknown Source)
W/FirebaseMessaging(10901):     at java.lang.Thread.run(Thread.java:761)
I/flutter (10901): On message {}
I/flutter (10901): {}
E/flutter (10901): [ERROR:flutter/shell/common/shell.cc(181)] Dart Error: Unhandled exception:
E/flutter (10901): NoSuchMethodError: The method '[]' was called on null.
E/flutter (10901): Receiver: null
E/flutter (10901): Tried calling: []("title")

但是，当应用程序处于后台时，通知会直接发送到系统托盘并且它不是空的 (screenshot).

这是我的颤振医生输出：

    [✓] Flutter (Channel beta, v0.8.2, on Mac OS X 10.13.5 17F77, locale es-ES)
    • Flutter version 0.8.2 at /Users/alex/Documents/Development/flutter
    • Framework revision 5ab9e70727 (3 weeks ago), 2018-09-07 12:33:05 -0700
    • Engine revision 58a1894a1c
    • Dart version 2.1.0-dev.3.1.flutter-760a9690c2

[✓] Android toolchain - develop for Android devices (Android SDK 27.0.3)
    • Android SDK at /Users/alex/Library/Android/sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-27, build-tools 27.0.3
    • ANDROID_HOME = /Users/alex/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)
    • All Android licenses accepted.

[✓] iOS toolchain - develop for iOS devices (Xcode 9.4.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.4.1, Build version 9F2000
    • ios-deploy 1.9.2
    • CocoaPods version 1.5.3

[✓] Android Studio (version 3.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin version 26.0.1
    • Dart plugin version 173.4700
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)

[✓] IntelliJ IDEA Ultimate Edition (version 2018.1.1)
    • IntelliJ at /Applications/IntelliJ IDEA.app
    • Flutter plugin version 26.0.2
    • Dart plugin version 181.4445.29

[✓] VS Code (version 1.27.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 2.18.0

[✓] Connected devices (1 available)
    • Android SDK built for x86 • emulator-5554 • android-x86 • Android 7.0 (API 24) (emulator)

• No issues found!

也许这与 Firebase 消息的工作方式有关？

Answer 1

已通过将 (1)firebase-messaging 和 (2)flutter_local_notifications 更新到其最新版本来解决此问题。