如何在Android O中设置Firebase通知ChannelID?

对于API级别26，我们必须设置一个通道ID作为参考.我了解了如何在没有channelID的情况下进行操作，下面是我的Firebase消息传递设置代码.但是现在适用于新的Android api 26级别

For API level 26 we have to set a channel id as a reference. I learned how to do it without a channelID and below there is my firebase messaging set-up code. But now for the new Android api 26 level

NotificationCompat.Builder(this);

这不起作用，我应该添加对channelID的引用为

This doesn't work and I should add a reference to channelID as

NotificationCompat.Builder(this, channelID);

但是我不知道该怎么做. 您可以帮助我了解如何为Firebase云消息传递创建频道ID吗?

But I don't know how to do it. Can you help me to understand how to create a channel ID for Firebase cloud messaging?

AndroidManifest.xml

    <service android:name=".MyFirebaseInstanceIdService">
        <intent-filter>
            <action android:name="com.google.firebase.INSTANCE_ID_EVENT"></action>
        </intent-filter>
    </service>

    <service android:name=".MyFirebaseMessagingService">
        <intent-filter>
            <action android:name="com.google.firebase.MESSAGING_EVENT"></action>
        </intent-filter>
    </service>

MyFirebaseInstanceIdService Java类:

import android.util.Log;
import com.google.firebase.iid.FirebaseInstanceId;
import com.google.firebase.iid.FirebaseInstanceIdService;

public class MyFirebaseInstanceIdService extends FirebaseInstanceIdService {

    private static final String REG_TOKEN = "REG_TOKEN";

    @Override
    public void onTokenRefresh() {
        String recent_token = FirebaseInstanceId.getInstance().getToken();
        Log.d(REG_TOKEN, recent_token);
    }
}

MyFirebaseMessagingService Java类

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.support.v4.app.NotificationCompat;

import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

public class MyFirebaseMessagingService extends FirebaseMessagingService {

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {

        Intent intent = new Intent(this, MainActivity.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);

        // Here I will set up a channel ID as "CH_ID_1" but I do not know how to do this.
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this, "CH_ID_1");
        //****************************************************

        notificationBuilder.setContentTitle("FCM NOTIFICATION");
        notificationBuilder.setContentText(remoteMessage.getNotification().getBody());
        notificationBuilder.setAutoCancel(true);
        notificationBuilder.setSmallIcon(R.mipmap.ic_launcher);
        notificationBuilder.setContentIntent(pendingIntent);
        NotificationManager notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.notify(0, notificationBuilder.build());

    }
}

等级-依赖项

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.0'
    implementation 'com.android.support:design:26.1.0'
    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.google.firebase:firebase-core:16.0.0'
    implementation 'com.google.firebase:firebase-messaging:17.0.0'
}
apply plugin: 'com.google.gms.google-services'