flutter - Flutter项目中的Application.kt提供错误-无法访问 'com.google.firebase.messaging.zzf'

Question

My application.kt文件如下:

import io.flutter.app.FlutterApplication
import io.flutter.plugin.common.PluginRegistry
import io.flutter.plugin.common.PluginRegistry.PluginRegistrantCallback
import io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService


class Application : FlutterApplication(), PluginRegistrantCallback {
    override fun onCreate() {
        super.onCreate()
        FlutterFirebaseMessagingService.setPluginRegistrant(this)
    }

    override fun registerWith(registry: PluginRegistry?) {
        io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin.registerWith(registry?.registrarFor("io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin"));
    }
}

我得到的错误:

Cannot access 'com.google.firebase.messaging.zzf' which is a supertype 
of 'io.flutter.plugins.firebasemessaging.FlutterFirebaseMessagingService'.
Check your module classpath for missing or conflicting dependencies

错误所在的行是 FlutterFirebaseMessagingService.setPluginRegistrant(this)。
我的 android/build.gradle文件具有以下实现代码:

dependencies {
        classpath 'com.android.tools.build:gradle:3.5.3'
        classpath 'com.google.gms:google-services:4.3.2'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }

我已经尝试了很多搜索，但仍然遇到这个问题。这是怎么了？

Answer 1

尝试这个
在android/build.gradle中添加classpath 'com.google.gms:google-services:4.3.3'在android/app/build.gradle中添加implementation "com.google.firebase:firebase-messaging:20.1.0" 或
尝试这个

override fun registerWith(registry: PluginRegistry?) {
        registry?.registrarFor("io.flutter.plugins.firebasemessaging.FirebaseMessagingPlugin");
    }