FCM Xamarin.Forms，iOS 背景通知不显示

Question

平台：iOS 10.2+

Xamarin 插件：Firebase iOS 云消息传递 https://components.xamarin.com/view/firebaseioscloudmessaging

问题：当我从 FireBase 控制台或从调用 FireBase 的代码发送通知时。我的iPhone没有收到后台通知(作为气泡(。但是，如果我将应用程序放在前台，我会收到来自函数ApplicationReceivedRemoteMessage(RemoteMessage remoteMessage(的"DisplayAlert"通知。

因此，设备在 FCM 上注册，设备具有令牌，设备可以接收通知，但设备未在后台接收通知。

**在.iOS项目清单的VisualStudio 2017中，我激活了后台模式，并激活了远程通知**

¿这是一个常见问题吗？ ¿我可以解决在我的项目中工作吗？

应用委托代码

[Register("AppDelegate")]
public partial class AppDelegate : global::Xamarin.Forms.Platform.iOS.FormsApplicationDelegate, IUNUserNotificationCenterDelegate, IMessagingDelegate
{
protected SQLiteAsyncConnection conn;
//
// This method is invoked when the application has loaded and is ready to run. In this 
// method you should instantiate the window, load the UI into it and then make the window
// visible.
//
// You have 17 seconds to return from this method, or iOS will terminate your application.
//
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
global::Xamarin.Forms.Forms.Init();
global::Xamarin.FormsMaps.Init();
CachedImageRenderer.Init();
LoadApplication(new App());
UITabBar.Appearance.SelectedImageTintColor = UIColor.FromRGB(139, 194, 77);
UINavigationBar.Appearance.TintColor = UIColor.FromRGB(139,194,77);
CrossVersionTracking.Current.Track();
// Firebase component initialize
Firebase.Analytics.App.Configure();
// Register your app for remote notifications.
if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))
{
// iOS 10 or later
var authOptions = UNAuthorizationOptions.Alert | UNAuthorizationOptions.Badge | UNAuthorizationOptions.Sound;
UNUserNotificationCenter.Current.RequestAuthorization(authOptions, (granted, error) => {
Console.WriteLine(granted);
});
// For iOS 10 display notification (sent via APNS)
UNUserNotificationCenter.Current.Delegate = this;
// For iOS 10 data message (sent via FCM)
Messaging.SharedInstance.RemoteMessageDelegate = this;
}
else
{
// iOS 9 or before
var allNotificationTypes = UIUserNotificationType.Alert | UIUserNotificationType.Badge | UIUserNotificationType.Sound;
var settings = UIUserNotificationSettings.GetSettingsForTypes(allNotificationTypes, null);
UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
}
UIApplication.SharedApplication.RegisterForRemoteNotifications();
Firebase.InstanceID.InstanceId.Notifications.ObserveTokenRefresh((sender, e) =>
{
newToken = Firebase.InstanceID.InstanceId.SharedInstance.Token;
//Conectamos con la base de datos.
database = new SQLiteClient();
conn = database.GetConnection();
usuario = null;
try
{
var task = Task.Run(async () =>
{
usuario = await conn.Table<Usuario>()
.FirstOrDefaultAsync();
});
task.Wait();
if (usuario != null)
{
usuario.token = newToken;
task = Task.Run(async () =>
{
await conn.InsertOrReplaceAsync(usuario);
});
task.Wait();
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("TOKEN ERRORtNo se ha podido Guardar el Token" + ex.Message);
}

System.Diagnostics.Debug.WriteLine("TOKENt" + newToken);
connectFCM();
});
#endregion
return base.FinishedLaunching(app, options);
}
public override void DidEnterBackground(UIApplication uiApplication)
{
Messaging.SharedInstance.Disconnect();
Console.WriteLine("Disconnected from FCM");
}
public override void OnActivated(UIApplication uiApplication)
{
connectFCM();
base.OnActivated(uiApplication);
}
public override void RegisteredForRemoteNotifications(UIApplication application, NSData deviceToken)
{
#if DEBUG
Firebase.InstanceID.InstanceId.SharedInstance.SetApnsToken(deviceToken, Firebase.InstanceID.ApnsTokenType.Sandbox);
#endif
#if RELEASE
Firebase.InstanceID.InstanceId.SharedInstance.SetApnsToken(deviceToken, Firebase.InstanceID.ApnsTokenType.Prod);
#endif
}
// iOS 9 <=, fire when recieve notification foreground
public override void DidReceiveRemoteNotification(UIApplication application, NSDictionary userInfo, Action<UIBackgroundFetchResult> completionHandler)
{
Messaging.SharedInstance.AppDidReceiveMessage(userInfo);
// Generate custom event
NSString[] keys = { new NSString("Event_type") };
NSObject[] values = { new NSString("Recieve_Notification") };
var parameters = NSDictionary<NSString, NSObject>.FromObjectsAndKeys(keys, values, keys.Length);
// Send custom event
Firebase.Analytics.Analytics.LogEvent("CustomEvent", parameters);
if (application.ApplicationState == UIApplicationState.Active)
{
System.Diagnostics.Debug.WriteLine(userInfo);
var aps_d = userInfo["aps"] as NSDictionary;
var alert_d = aps_d["alert"] as NSDictionary;
var body = alert_d["body"] as NSString;
var title = alert_d["title"] as NSString;
debugAlert(title, body);
}
}
// iOS 10, fire when recieve notification foreground
[Export("userNotificationCenter:willPresentNotification:withCompletionHandler:")]
public void WillPresentNotification(UNUserNotificationCenter center, UNNotification notification, Action<UNNotificationPresentationOptions> completionHandler)
{
System.Console.WriteLine(notification.Request.Content.UserInfo);
var title = notification.Request.Content.Title;
var body = notification.Request.Content.Body;
debugAlert(title, body);
}
private void connectFCM()
{
Console.WriteLine("connectFCMtEjecutandose la función.");
Messaging.SharedInstance.Connect((error) =>
{
if (error == null)
{
//TODO: Change Topic to what is required
Messaging.SharedInstance.Subscribe("/topics/all");
}
//System.Diagnostics.Debug.WriteLine("connectFCMt" + (error != null ? "error occured" : "connect success"));
Console.WriteLine("connectFCMt" + (error != null ? "error occured" + error.DebugDescription : "connect success"));
});
}
private void debugAlert(string title, string message)
{
var alert = new UIAlertView(title ?? "Title", message ?? "Message", null, "Cancel", "OK");
alert.Show();
}
public void ApplicationReceivedRemoteMessage(RemoteMessage remoteMessage)
{
Console.WriteLine("n*******************************************");
Console.WriteLine("AplicationReceivedRemoteMessaget" + remoteMessage.AppData);
Console.WriteLine("n*******************************************");
var title = remoteMessage.AppData.ValueForKey(new NSString("title"));
var text = remoteMessage.AppData.ValueForKey(new NSString("text"));
debugAlert("" + title,  "" + text);
}
[Export("userNotificationCenter:didReceiveNotificationResponse:withCompletionHandler:")]
public void DidReceiveNotificationResponse(UNUserNotificationCenter center, UNNotificationResponse response, Action completionHandler)
{
debugAlert("DidreceiveNotificationResponse", response + ""  );
}

有关更多信息，我的 info.plist 包含密钥：

<key>UIBackgroundModes</key>
<array>
<string>location</string>
<string>bluetooth-central</string>
<string>bluetooth-peripheral</string>
<string>fetch</string>
<string>remote-notification</string>
</array>

Answer 1

经过长时间的调查，我解决了它。

有必要将该密钥添加到Entile.plist文件中。

<dict>
<key>aps-environment</key>
<string>development</string>
</dict>