Flutter firebase_message plugin setup errors - flutter

Question

I wanted to try out cloud messaging in my Flutter application, but I always run into errors, and I have not found a solution yet. I followed the steps stated here: firebase_messaging
If I follow the steps except the optional part with creating an Application.java file for background messages, and I send a test message from Firebase to the launched application, I get this error:
java.lang.RuntimeException: Unable to create service io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService: java.lang.RuntimeException: PluginRegistrantCallback is not set.
at android.app.ActivityThread.handleCreateService(ActivityThread.java:3577)
at android.app.ActivityThread.access$1400(ActivityThread.java:200)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1689)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:201)
at android.app.ActivityThread.main(ActivityThread.java:6806)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
E/AndroidRuntime(29468): Caused by: java.lang.RuntimeException: PluginRegistrantCallback is not set.
at io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService.startBackgroundIsolate(FlutterFirebaseMessagingService.java:157)
at io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService.onCreate(FlutterFirebaseMessagingService.java:77)
at android.app.ActivityThread.handleCreateService(ActivityThread.java:3565)
For me it seems like that the optional part is needed too, but when I do that I get errors when the app opens. After the errors the app still runs, and if I send a test message from Firebase the app receives it succesfully. Later it doesn't even receives the message, but thows the same errors.
java.lang.NullPointerException: Attempt to invoke virtual method 'android.app.Application android.app.Activity.getApplication()' on a null object reference
at com.github.adee42.keyboardvisibility.KeyboardVisibilityPlugin.registerWith(KeyboardVisibilityPlugin.java:107)
at io.flutter.plugins.GeneratedPluginRegistrant.registerWith(GeneratedPluginRegistrant.java:22)
at io.flutter.plugins.Application.registerWith(Application.java:18)
at io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService.startBackgroundIsolate(FlutterFirebaseMessagingService.java:164)
at io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin.onMethodCall(FirebaseMessagingPlugin.java:133)
at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:222)
at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:96)
at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:656)
at android.os.MessageQueue.nativePollOnce(Native Method)
at android.os.MessageQueue.next(MessageQueue.java:326)
at android.os.Looper.loop(Looper.java:165)
at android.app.ActivityThread.main(ActivityThread.java:6806)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
[ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: PlatformException(error, Attempt to invoke virtual method 'android.app.Application android.app.Activity.getApplication()' on a null object reference, null)
StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:569:7)
MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:316:33)
<asynchronous suspension>
FirebaseMessaging.configure (package:firebase_messaging/firebase_messaging.dart:118:16)
main (package:vonatles/main.dart:18:22)
_AsyncAwaitCompleter.start (dart:async-patch/async_patch.dart:43:6)
main (package:vonatles/main.dart:12:10)
_runMainZoned.<anonymous closure>.<anonymous closure> (dart:ui/hooks.dart:229:25)
_rootRun (dart:async/zone.dart:1124:13)
_CustomZone.run (dart:async/zone.dart:1021:19)
_runZoned (dart:async/zone.dart:1516:10)
runZoned (dart:async/zone.dart:1500:12)
_runMainZoned.<anonymous closure> (dart:ui/hooks.dart:221:5)
_startIsolate.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:305:19)
_RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:172:12)
Versions:
firebase_core: ^0.4.0+1
firebase_database: 3.0.7
firebase_messaging: 5.1.5
classpath 'com.android.tools.build:gradle:3.3.0'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.3.0"
classpath 'com.google.gms:google-services:4.3.0'
In the Flutter main function I have this:
final FirebaseMessaging _firebaseMessaging = FirebaseMessaging();
_firebaseMessaging.configure(
onMessage: (Map<String, dynamic> message) async {
print("onMessage: $message");
},
onLaunch: (Map<String, dynamic> message) async {
print("onLaunch: $message");
},
onResume: (Map<String, dynamic> message) async {
print("onResume: $message");
},
);
The Application.java code:
package io.flutter.plugins;
import io.flutter.app.FlutterApplication;
import io.flutter.plugin.common.PluginRegistry;
import io.flutter.plugin.common.PluginRegistry.PluginRegistrantCallback;
import io.flutter.plugins.GeneratedPluginRegistrant;
import io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService;
public class Application extends FlutterApplication implements PluginRegistrantCallback {
#Override
public void onCreate() {
super.onCreate();
FlutterFirebaseMessagingService.setPluginRegistrant(this);
}
#Override
public void registerWith(PluginRegistry registry) {
GeneratedPluginRegistrant.registerWith(registry);
}
}
My android main directory:
-main
-java
-io.flutter.plugins
Apllication.java
GeneratedPluginRegistrant.java
-kotlin
-my.package.name
MainActivity.kt
AndroidManifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="my.package.name">
<application
android:name="io.flutter.plugins.Application"
android:label="mylabel"
android:icon="#mipmap/ic_launcher">
<activity
android:name=".MainActivity"
...
<intent-filter>
<action android:name="FLUTTER_NOTIFICATION_CLICK" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>

Answer 1

Since my MainActivity in android was a Kotlin class, I got the solution to this problem when I tried the Application class as a Kotlin class instead of trying it as a Java class.
I tried many solutions, still, I was not able to run the app.
Application.kt
package YOUR_PACKAGE_NAME
import io.flutter.app.FlutterApplication
import io.flutter.plugin.common.PluginRegistry
import io.flutter.plugin.common.PluginRegistry.PluginRegistrantCallback
import io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService
public class Application: FlutterApplication(), PluginRegistrantCallback {
override fun onCreate() {
super.onCreate()
FlutterFirebaseMessagingService.setPluginRegistrant(this)
}
override fun registerWith(registry: PluginRegistry) {
FirebaseCloudMessagingPluginRegistrant.registerWith(registry)
}
}
Also, FirebaseCloudMessagingPluginRegistrant.kt
package YOUR_PACKAGE_NAME
import io.flutter.plugin.common.PluginRegistry
import io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin
class FirebaseCloudMessagingPluginRegistrant {
companion object {
fun registerWith(registry: PluginRegistry) {
if (alreadyRegisteredWith(registry)) {
return;
}
FirebaseMessagingPlugin.registerWith(registry.registrarFor("io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin"))
}
fun alreadyRegisteredWith(registry: PluginRegistry): Boolean {
val key = FirebaseCloudMessagingPluginRegistrant::class.java.name
if (registry.hasPlugin(key)) {
return true
}
registry.registrarFor(key)
return false
}
}
}
This can be added in the sample directory where your MainActivity is.
Try this Along with the steps mentioned here: Firebase messaging

Answer 2

by the way you can create a notification_handler.dart like this Unhandled Exception: NoSuchMethodError: The method 'toRawHandle' was called on null.
i have posted my notification_handler.dart their.
try to configure with that and just call is as below from your statefullWidget and the let me know.
#override
void initState() {
super.initState();
new NotificationHandler().initializeFcmNotification();
}

Answer 3

Background notification setup is not optional anymore. Make sure to follow intructions properly. And i was confused in making change in AndroidManifest.xml, So i wanted to share clear instruction.
PluginRegistrantCallback is not set" means Application.java file is not called properly at AndroidManifest.xml. Make change as follows:
First it looks like this
Change it to yourpackagename.Application like this
If you get "Default activity not found" error, run "flutter clean" command in your project folder and run it again.

Answer 4

In your AndroidManifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="my.package.name">
<application
android:name=".Application" //edit this line
android:label="mylabel"
android:icon="#mipmap/ic_launcher">
<activity
android:name=".MainActivity"
...
<intent-filter>
<action android:name="FLUTTER_NOTIFICATION_CLICK" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>