模拟器未收到来自云消息的推送通知

Question

我尝试将云消息连接到我的应用程序，尝试了所有解决方案后，通知仍然没有到达。当我尝试在控制台中发送内容时，只写了这样的内容： 这是manifest.xml：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.example.myapp">


    <uses-permission android:name="android.permission.READ_MEDIA_IMAGES" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE"/>
    <uses-permission android:name="android.permission.WAKE_LOCK" />

    <application
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:noHistory="true"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Myapp"

        tools:targetApi="31">

        <activity
            android:name=".SignInActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".SignUpActivity"
            android:exported="true">
            <intent-filter>
                <action android:name=".SignUpActivity" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>

        <activity
            android:name=".CreatedWorkoutActivity"
            android:exported="false">
            <intent-filter>
                <action android:name=".CreatedWorkoutActivity" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>
        <activity
            android:name=".WorkoutMakerActivity"
            android:exported="true">
            <intent-filter>
                <action android:name=".WorkoutMakerActivity" />

                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
        </activity>

        <activity
            android:name=".MainActivity"
            android:exported="false">
        </activity>
        <activity
            android:name=".Pop"
            android:theme="@style/AppTheme.CustomTheme"
            >
        </activity>

        <service android:name=".FCMNotificationService"
            android:permission="com.google.android.c2dm.permission.SEND"
            android:exported="false">
            <intent-filter>
                <action android:name="com.google.firebase.MESSAGING_EVENT"/>
                <action android:name="com.google.android.c2dm.intent.RECEIVE"/>
            </intent-filter>
        </service>




        <meta-data
            android:name="com.google.firebase.messaging.default_notification_channel_id"
            android:value="@string/default_notification_channel_id" />

    </application>

</manifest>

FCMNotificationService.java：

package com.example.myapp;


import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.media.RingtoneManager;
import android.net.Uri;
import android.os.Build;
import android.util.Log;

import androidx.annotation.NonNull;
import androidx.core.app.NotificationCompat;


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

public class FCMNotificationService extends FirebaseMessagingService {

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {

        System.out.println("я тут");

        if (remoteMessage.getNotification()!=null){
            // Show the notification
            String notificationBody = remoteMessage.getNotification().getBody();
            String notificationTitle = remoteMessage.getNotification().getTitle();

            sendNotification (notificationTitle, notificationBody);

        }
    }


    private void sendNotification(String title, String body) {
        Intent intent = new Intent(this, MainActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
                PendingIntent.FLAG_IMMUTABLE);

        String channelId = "fcm_default_channel";
        Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationCompat.Builder notificationBuilder =
                new NotificationCompat.Builder(this, channelId)
                        .setSmallIcon(R.mipmap.ic_launcher)
                        .setContentTitle(title)
                        .setContentText(body)
                        .setAutoCancel(true)
                        .setSound(defaultSoundUri)
                        .setContentIntent(pendingIntent);

        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        // Since android Oreo notification channel is needed.
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel channel = new NotificationChannel(channelId,
                    "Channel human readable title",
                    NotificationManager.IMPORTANCE_DEFAULT);
            notificationManager.createNotificationChannel(channel);
        }

        notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
    }



}

我添加的 MainActivity 部分是为了解决此问题“应用程序尚未创建 AndroidManifest.xml 中设置的通知通道。将使用默认值。”：

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationManager notificationManager = getSystemService(NotificationManager.class);
            CharSequence name = getString(R.string.default_notification_channel_name);
            String description = getString(R.string.default_notification_channel_description);
            int importance = NotificationManager.IMPORTANCE_DEFAULT;
            NotificationChannel channel = new NotificationChannel(getString(R.string.default_notification_channel_id), name, importance);
            channel.setDescription(description);
            // Optionally set other channel settings such as lights, vibration, etc.
            notificationManager.createNotificationChannel(channel);
        }
        

模拟器版本：

我尝试添加很多东西来体现，但没有任何帮助。

Answer 1

从 API 级别 33 开始，您需要用户的许可才能在 Android 中显示推送通知。

参考：https://developer.android.com/develop/ui/views/notifications/notification-permission

在清单中声明权限，如下所示：

<uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>

来自文档：
如果您的应用面向 Android 13 或更高版本，则您的应用可以完全控制何时显示权限对话框。利用这个机会向用户解释为什么应用程序需要此权限，鼓励他们授予该权限。

如果您的应用程序的目标版本为 12L（API 级别 32）或更低，则当您的应用程序在创建通知通道后首次启动 Activity 时，或者当您的应用程序启动 Activity 然后创建其第一个通知通道时，系统会显示权限对话框。这通常是在应用程序启动时发生。