当应用程序处于前景状态时，无法接收FCM的通知

Question

我是Android和编程的新手，我正在创建一个从FCM接收消息的应用程序，它在应用程序处于后台时正常工作，所以我添加了一个FirebaseMessagingService类，它在onMessageReceived方法中接收通知，并跟踪谷歌文档，但当应用程序处于前台状态时，通知仍然不工作，我已经遵循了每一步，无法找出我的代码中的问题在哪里，因为日志对我没有帮助，我没有收到任何错误，除了这个错误，我不知道它是否是问题的来源：分析GCM事件java.lang.NumberFormatException中的时间戳时出错：s==空

这是我的MyFirebaseMessagingService类

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.support.v4.app.NotificationCompat;
import android.support.v4.app.NotificationManagerCompat;
import com.app.muhammadgamal.swapy.R;
import com.google.firebase.messaging.RemoteMessage;
public class MyFirebaseMessagingService extends com.google.firebase.messaging.FirebaseMessagingService {
@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
super.onMessageReceived(remoteMessage);
String click_Action = remoteMessage.getNotification().getClickAction();

String messageTitle = remoteMessage.getNotification().getTitle();
String messageBody = remoteMessage.getNotification().getBody();

NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(this, getString(R.string.default_notification_channel_id))
.setSmallIcon(R.drawable.ic_main_logo)
.setContentTitle(messageTitle)
.setContentText(messageBody)
.setPriority(NotificationCompat.PRIORITY_DEFAULT);

Intent intent = new Intent(click_Action);
PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
mBuilder.setContentIntent(pendingIntent);

int mNotificationID = (int)System.currentTimeMillis();
NotificationManager manager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
manager.notify(mNotificationID,mBuilder.build());
}
}

和我的清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.app.muhammadgamal.swapy">
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_main_logo"
android:label="@string/app_name"
android:roundIcon="@drawable/ic_main_logo"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity
android:name=".Activities.SignInActivity"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Activities.SignUpActivity"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".Activities.ProfileActivity"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".Activities.NavDrawerActivity"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".Activities.SwapCreationActivity"
android:theme="@style/AppTheme.NoActionBar" />
<activity android:name=".Activities.ReceivedSwapRequest">
<intent-filter>
<action android:name="com.app.muhammadgamal.swapy.Activities.ReceivedSwapRequest_NOTIFICATION_TASK"></action>
<category android:name="android.intent.category.DEFAULT"></category>
</intent-filter>
</activity>
<service
android:name=".Notifications.MyFirebaseMessagingService">
<intent-filter>
<action android:name="com.google.firebase.MESSAGING_EVENT"/>
</intent-filter>
</service>
</application>
</manifest>

和我的索引函数

'use strict'

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);

exports.sendNotification = functions.database.ref('/Notifications/{receiver_user_id}/{notification_id}')
.onWrite((data, context) =>
{
const receiver_user_id = context.params.receiver_user_id;
const notification_id = context.params.notification_id;

console.log('We have a notification to send to :' , receiver_user_id);

if (!data.after.val()) 
{
console.log('A notification has been deleted :' , notification_id);
return null;
}
const DeviceToken = admin.database().ref(`/Users/${receiver_user_id}/device_token`).once('value');
return DeviceToken.then(result => 
{
const token_id = result.val();
const payload = 
{
notification:
{
title: "New Swap Request",
body: `you have a new Swap Request, Please Check.`,
click_action: "com.app.muhammadgamal.swapy.Activities.ReceivedSwapRequest_NOTIFICATION_TASK"
}
};
return admin.messaging().sendToDevice(token_id, payload)
.then(response => 
{
return console.log('This was a notification feature.');
});
});
});

Answer 1

我发现了问题，这是因为我使用的是Android O，没有为通知设置频道ID，如果你想在Android 8.0或更高版本的上接收它，这是必须的

这是解决方案代码

private void createNotificationChannel() {
// Create the NotificationChannel, but only on API 26+ because
// the NotificationChannel class is new and not in the support library
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
CharSequence name = getString(R.string.channel_name);
String description = getString(R.string.channel_description);
int importance = NotificationManager.IMPORTANCE_DEFAULT;
NotificationChannel channel = new NotificationChannel(CHANNEL_ID, name, importance);
channel.setDescription(description);
// Register the channel with the system; you can't change the importance
// or other notification behaviors after this
NotificationManager notificationManager = getSystemService(NotificationManager.class);
notificationManager.createNotificationChannel(channel);
}
}