Unresolved class for firebase ".MyFirebaseInstanceIDService" and ".java.MyFirebaseMessagingService"

Question

I'm trying to import Firebase and FCM into my android app, but I'm getting

Unresolved class for firebase ".MyFirebaseInstanceIDService" Unresolved package for firebase ".java.MyFirebaseMessagingService"

as an "error." Of course, it isn't stopping my app from running or building, but I cannot call onTokenRefresh in any class at all. So, I believe this problem is preventing me from using Firebase.

here is my app build;

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.northlandcaps.crisis_response"
        minSdkVersion 21
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

    }
    buildTypes {
        release {
            android {
                lintOptions {
                    checkReleaseBuilds false
                    // Or, if you prefer, you can continue to check for errors in release builds,
                    // but continue the build even when errors are found:
                    abortOnError false
                }
            }
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation 'com.google.firebase:firebase-core:16.0.5'
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    //noinspection GradleCompatible
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation 'com.android.support:mediarouter-v7:28.0.0'
    implementation 'com.android.volley:volley:1.1.0'
    implementation 'com.android.support:recyclerview-v7:28.0.0'
    implementation 'com.google.firebase:firebase-messaging:17.3.4'
}
apply plugin: 'com.google.gms.google-services'

Screenshot of problem

Answer 1

This how you two classes should look like:

public class MyFirebaseInstanceIDService extends FirebaseInstanceIdService {
    private static final String TAG = "MyFirebaseIIDService";

    @Override
    public void onTokenRefresh() {
        super.onTokenRefresh();

        String refreshedToken = FirebaseInstanceId.getInstance().getToken();
        Log.d(TAG, "Refreshed token: " + refreshedToken);

        sendRegistrationToServer(refreshedToken);
    }

    private void sendRegistrationToServer(String token) {
        // Add custom implementation, as needed.
    }
}

And:

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        super.onMessageReceived(remoteMessage);
        RemoteMessage.Notification notification = remoteMessage.getNotification();
        Map<String, String> data = remoteMessage.getData();

        sendNotification(notification, data);
    }

    private void sendNotification(RemoteMessage.Notification notification, Map<String, String> data) {
        //Send notification
    }
}