在 xamarin 中关闭应用程序时接收推送通知

Question

当应用程序完全关闭时，我正在尝试在 Xamarin 中处理 GCM 推送通知。按照 Xamarin 推送通知教程，我可以从 GCM 接收远程/推送通知，但是一旦我关闭应用程序，我就没有收到。这是我迄今为止尝试过的：

1.广播接收器：

    public class MyGCMBroadcastReceiver : BroadcastReceiver {

    public override void OnReceive (Context context, Intent intent)
    {
        Intent gcmListenerServiceIntent = new Intent(context,typeof(MyGcmListenerService));
        Console.WriteLine ("Starting Broadcast Receiver...");
        context.StartService (gcmListenerServiceIntent);
    }
}

2. 显现：

   <uses-permission android:name="android.permission.WAKE_LOCK" />
   <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
   <uses-permission android:name="za.co.snappyhome.snappy.permission.C2D_MESSAGE" />
   <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
   <uses-permission android:name="android.permission.INTERNET" />
   <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
   <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
   <uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
   <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
   <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
   <uses-permission android:name="android.permission.CALL_PHONE" />
   <uses-permission android:name="android.permission.CALL_PRIVILEGED" />
   <uses-permission android:name="android.permission.CAMERA" />
   <uses-permission android:name="android.permission.VIBRATE" />
   <application android:label="My App" android:theme="@style/AppTheme" android:icon="@drawable/icon">
   <receiver android:name="com.google.android.gms.gcm.GcmReceiver"
             android:exported="true"
       android:permission="com.google.android.c2dm.permission.SEND">
       <intent-filter>
           <action android:name="com.google.android.c2dm.intent.RECEIVE" />
           <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
           <category android:name="za.co.myapp.app" />
       </intent-filter>
   </receiver>
   <receiver android:name="MyApp.Droid.Notifications.MyGCMBroadcastReceiver">
       <intent-filter>
          <actionandroid:name="android.intent.action.BOOT_COMPLETED"/>                  
       </intent-filter>
   </receiver>
   </application>
   

3. GCM监听器服务：

   [Service (Exported = false), IntentFilter (new [] { "com.google.android.c2dm.intent.RECEIVE" })]
   public class MyGcmListenerService : GcmListenerService
   {
   
   public override void OnMessageReceived (string from, Bundle data)
   {
       if (data.ContainsKey ("data")) {
   
           if (Xamarin.Forms.Application.Current != null) {
               String json = data.GetString("data");
   
               MessagingCenter.Send<Xamarin.Forms.Application, string> (Xamarin.Forms.Application.Current,
                   "NOTIFICATION_MESSAGE_RECEIVED", json);                 
           }
       }
   }
   

   }

我仍在掌握 Xamarin 和 GCM 通知，所以我的理解可能是错误的。我的理解是我可以在应用程序启动时启动广播接收器。这将反过来启动一个可以监听推送通知的服务（在我的例子中是 MyGcmListenerService）。我的第一个问题是广播接收器不会在应用程序启动时启动（按照这个答案：尝试在 Android 启动时启动服务）。其次，是否可以调用 MyGcmListenerService 以开始收听我正在尝试做的通知。我试过使用 GCMIntentService，但它似乎已被弃用： 当应用程序关闭时推送通知

先感谢您！！

Answer 1

我在 Xamarin Native - Android 中使用了以下配置和代码段，并且可以在应用程序关闭时看到通知。

1. Android 清单.xml

   <receiver android:name="com.google.firebase.iid.FirebaseInstanceIdInternalReceiver" android:exported="false" />
           <receiver android:name="com.google.firebase.iid.FirebaseInstanceIdReceiver" android:exported="true" android:permission="com.google.android.c2dm.permission.SEND">
               <intent-filter>
                   <action android:name="com.google.android.c2dm.intent.RECEIVE" />
                   <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
                   <category android:name="${applicationId}" />
               </intent-filter>
           </receiver>
   
   <service android:name="HEET.Droid.ViewController.Login.FireBaseIIDService" android:permission="false" android:stopWithTask="false">
               <intent-filter>
                   <action android:name="com.google.firebase.messaging_event" />
               </intent-filter>
           </service>
   

   2. FireBaseIIDService.cs

根据最新版本，在 FireBaseIIDService 意图服务类中， onMessageReceived(RemoteMessage msg) 将在接收每条消息时调用。

        [Service]
        [IntentFilter(new[] { "com.google.firebase.MESSAGING_EVENT" })]
        public class FireBaseIIDService : FirebaseMessagingService{

   public override void OnMessageReceived (RemoteMessage msg) {
Notification.Builder builder = new Notification.Builder(this, "my_notification_channel");
            builder.SetSmallIcon(Resource.Drawable.circle);
            var intent = new Intent(this, typeof(DashboardActivity));
            intent.AddFlags(ActivityFlags.ClearTop);
            PendingIntent pendingIntent = PendingIntent.GetActivity(this, 0, intent, 0);
            builder.SetContentIntent(pendingIntent);
            builder.SetLargeIcon(BitmapFactory.DecodeResource(Resources, Resource.Drawable.circle));
            builder.SetContentTitle(Header);
            builder.SetContentText(body);
            builder.SetDefaults(NotificationDefaults.Sound);
            builder.SetAutoCancel(true);
            NotificationManager notificationManager = (NotificationManager)GetSystemService(NotificationService);
            notificationManager.Notify(1, builder.Build());
    }
    }