React Native OneSignal Background Notification Issue in iOS

Question

I followed this guide to setup the OneSignal background notification in My react native App: https://documentation.onesignal.com/docs/rn-android-native-module-setup-for-notification-service-extension#ios-notification-service-extension-module

Background notification is working as expected when I installed the App directly to My device through Xcode. But when I archive the build and install it from TestFlight, background notification doesn't work. Unless emitNotificationEvent event I added is not get triggered, even though the push notification is received.

When I trace the issue with Archived Build in Xcode (Using device console), noticed that _instance is null in NotificationExtensionModule.m . Anyone experienced similar issue or any idea what could be the reason?

Note

• Xcode Version: 13.4
• Receiving the push notification in both instance (from test flight or direct install)
• To put a new version in TestFlight, used to increase the build number with same version number.
• Tried cleaning the build folder, re-installing the pods, nothing worked still

Adding the code snippet for further understanding of My issue:

AppDelegate.h

#import <Foundation/Foundation.h>
#import <React/RCTBridgeDelegate.h>
#import <UIKit/UIKit.h>
#import <UserNotifications/UserNotifications.h>


@interface AppDelegate : UIResponder <UIApplicationDelegate,RCTBridgeDelegate,UNUserNotificationCenterDelegate>

@property (nonatomic, strong) UIWindow *window;

@end

AppDelegate.m

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{
  //access NotificationServiceExtensionModule emitNotificationEvent method
  [NotificationServiceExtensionModule.sharedInstance emitNotificationEvent:userInfo ];
  completionHandler(UIBackgroundFetchResultNoData);
}

NotificationServiceExtensionModule.h

#import <foundation/Foundation.h>

// NotificationServiceExtensionModule.h
#import <React/RCTBridgeModule.h>
#import <React/RCTEventEmitter.h>

@interface NotificationServiceExtensionModule : RCTEventEmitter <RCTBridgeModule>

+ (NotificationServiceExtensionModule*) sharedInstance;
- (void)emitNotificationEvent:(NSDictionary *)userInfo;


@end

NotificationServiceExtensionModule.m

#import <Foundation/Foundation.h>

// NotificationServiceExtensionModule.m
#import "NotificationServiceExtensionModule.h"

@implementation NotificationServiceExtensionModule

static NotificationServiceExtensionModule* _instance = nil;


+(NotificationServiceExtensionModule*) sharedInstance {
//    @synchronized( _instance ) {
//        if( !_instance ) {
//            _instance = [[NotificationServiceExtensionModule alloc] init];
//        }
//    }
    
    return _instance; // this returns null when installed from TestFlight. 
}

// To export a module named NotificationServiceExtensionModule
RCT_EXPORT_MODULE();

- (NSArray<NSString *> *)supportedEvents
{
  NSLog(@"Supported EVENTS__________________________");
  _instance = self;
  return @[@"NotificationEvent"];
}

- (void)emitNotificationEvent:(NSDictionary *)userInfo
{
  NSString *eventName = userInfo[@"custom"][@"a"];
  [self sendEventWithName:@"NotificationEvent" body:@{@"notificationPayload": eventName}];
}

@end

Answer 1

You can use the following code to check if the app is running in the background or foreground:

- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{
  //access NotificationServiceExtensionModule emitNotificationEvent method
  [NotificationServiceExtensionModule.sharedInstance emitNotificationEvent:userInfo ];
  if (application.applicationState == UIApplicationStateActive) {
    // App was in the foreground when the notification was received
  } else {
    // App was in the background when the notification was received
  }
  completionHandler(UIBackgroundFetchResultNoData);
}