Estou tentando implementar chamadas App-to-App com Sinch no meu aplicativo IOS. Eu implementei o Pushkit no meu aplicativo iOS com o Sinch, mas a notificação por push não está funcionando quando o aplicativo está em segundo plano.

Eu tenho duas perguntas.

Preciso de outro serviço da web para enviar notificação por push ao meu aplicativo para o aplicativo recebido separadamente ou o Sinch lida com ele mesmo.

Se ele se resolver, então o que estou perdendo no meu código.

#import "AppDelegate.h"
@interface AppDelegate ()
@end

@implementation AppDelegate


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    UIUserNotificationSettings* notificationSettings = [UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert | UIUserNotificationTypeBadge | UIUserNotificationTypeSound categories:nil];
    [[UIApplication sharedApplication] registerUserNotificationSettings:notificationSettings];

    [self handleLocalNotification:[launchOptions objectForKey:UIApplicationLaunchOptionsLocalNotificationKey]];

    self.push = [Sinch managedPushWithAPSEnvironment:SINAPSEnvironmentAutomatic];
    self.push.delegate = self;
    [self.push setDesiredPushTypeAutomatically];

    [self.push registerUserNotificationSettings];

    return YES;
 }
 - (BOOL)application:(UIApplication *)app
        openURL:(NSURL *)url
        options:(NSDictionary *)options {
    return [[GIDSignIn sharedInstance] handleURL:url
                           sourceApplication:options[UIApplicationOpenURLOptionsSourceApplicationKey]
                                  annotation:options[UIApplicationOpenURLOptionsAnnotationKey]];
  }

- (BOOL)application:(UIApplication *)application
        openURL:(NSURL *)url
  sourceApplication:(NSString *)sourceApplication
     annotation:(id)annotation {
    return [[GIDSignIn sharedInstance] handleURL:url
                           sourceApplication:sourceApplication
                                  annotation:annotation];
}

- (id<SINClient>)client {
   return _sinchClient;
}
-(void)clientDidFail:(id<SINClient>)client error:(NSError *)error{

   NSLog(@"fail");
}

-(void)clientDidStart:(id<SINClient>)client{

    NSLog(@"Start");
    [self voipRegistration];
}


- (void)client:(id<SINClient>)client
   logMessage:(NSString *)message
      area:(NSString *)area
    severity:(SINLogSeverity)severity
   timestamp:(NSDate *)timestamp {
// If you want all messages remove the if statement

    if (severity == SINLogSeverityCritical) {
        NSLog(@"%@", message);
    }
}

- (void)initSinchClientWithUserId:(NSString *)userId {
    if (!_sinchClient) {

        _sinchClient = [Sinch clientWithApplicationKey:@"<my-key>"
                                applicationSecret:@"<my-secret>"
                                  environmentHost:@"sandbox.sinch.com"
                                           userId:userId];

        _sinchClient.delegate = self;

        [_sinchClient setSupportCalling:YES];
        [_sinchClient startListeningOnActiveConnection];
        [_sinchClient enableManagedPushNotifications];
        [_sinchClient start];
    }
 }
 - (void)handleLocalNotification:(UILocalNotification *)notification {
    if (notification) {
        id<SINNotificationResult> result = [self.sinchClient      relayLocalNotification:notification];
        if ([result isCall] && [[result callResult] isTimedOut]) {
            UIAlertView *alert = [[UIAlertView alloc]
                                  initWithTitle:@"Missed call"
                                  message:[NSString stringWithFormat:@"Missed call from %@", [[result callResult] remoteUserId]]
                                  delegate:nil
                                  cancelButtonTitle:nil
                                  otherButtonTitles:@"OK", nil];
            [alert show];
        }
    }
}

-(void)voipRegistration
{
    PKPushRegistry* voipRegistry = [[PKPushRegistry alloc] initWithQueue:dispatch_get_main_queue()];
    voipRegistry.delegate = self;
    voipRegistry.desiredPushTypes = [NSSet setWithObject:PKPushTypeVoIP];
}

-(void)pushRegistry:(PKPushRegistry *)registry didUpdatePushCredentials:(PKPushCredentials *)credentials forType:(NSString *)type
{
    [_sinchClient registerPushNotificationData:credentials.token];
}
-(void)pushRegistry:(PKPushRegistry *)registry   didInvalidatePushTokenForType:(PKPushType)type{

     NSLog(@"invalidated");
}
-(void)pushRegistry:(PKPushRegistry *)regist,ry   didReceiveIncomingPushWithPayload:(PKPushPayload *)payload forType:  (NSString *)type
{
    //notify
    NSDictionary* dic = payload.dictionaryPayload;
    NSString* sinchinfo = [dic objectForKey:@"sin"];
    UILocalNotification* notif = [[UILocalNotification alloc] init];
    notif.alertBody = @"incoming call";
    [[UIApplication sharedApplication] presentLocalNotificationNow:notif];
    if (sinchinfo == nil)
        return;

    dispatch_async(dispatch_get_main_queue(), ^{
        [_sinchClient relayRemotePushNotificationPayload:sinchinfo];
    });
}