Fix stopObserving on reload issue

ios/RNVoipPushNotification/RNVoipPushNotificationManager.m

@@ -30,27 +30,34 @@ @implementation RNVoipPushNotificationManager
 static NSString *_lastVoipToken = @"";
 static NSMutableDictionary<NSString *, RNVoipPushNotificationCompletion> *completionHandlers = nil;
 
-
 // =====
 // ===== RN Module Configure and Override =====
 // =====
 
+-(instancetype) init
+{
+    return [[self class] sharedInstance];
+}
 
-- (instancetype)init
+-(instancetype) initPrivate
 {
     if (self = [super init]) {
         _delayedEvents = [NSMutableArray array];
     }
+
     return self;
 }
 
-+ (id)allocWithZone:(NSZone *)zone {
-    static RNVoipPushNotificationManager *sharedInstance = nil;
+// Singletone implementation based on https://stackoverflow.com/q/5720029/3686678 and https://stackoverflow.com/a/7035136/3686678
++(instancetype) sharedInstance
+{
+    static RNVoipPushNotificationManager *sharedVoipPushManager = nil;
     static dispatch_once_t onceToken;
     dispatch_once(&onceToken, ^{
-        sharedInstance = [super allocWithZone:zone];
+        sharedVoipPushManager = [[self alloc] initPrivate];
     });
-    return sharedInstance;
+
+    return sharedVoipPushManager;
 }
 
 // --- clean observer and completionHandlers when app close
@@ -94,12 +101,6 @@ - (void)startObserving
     }
 }
 
-- (void)stopObserving
-{
-    _hasListeners = NO;
-}
-
-
 
 // =====
 // ===== Class Method =====
@@ -126,7 +127,7 @@ + (void)voipRegistration
 #ifdef DEBUG
         RCTLog(@"[RNVoipPushNotificationManager] voipRegistration is already registered. return _lastVoipToken = %@", _lastVoipToken);
 #endif
-        RNVoipPushNotificationManager *voipPushManager = [RNVoipPushNotificationManager allocWithZone: nil];
+        RNVoipPushNotificationManager *voipPushManager = [RNVoipPushNotificationManager sharedInstance];
         [voipPushManager sendEventWithNameWrapper:RNVoipPushRemoteNotificationsRegisteredEvent body:_lastVoipToken];
     } else {
         _isVoipRegistered = YES;
@@ -164,7 +165,7 @@ + (void)didUpdatePushCredentials:(PKPushCredentials *)credentials forType:(NSStr
 
     _lastVoipToken = [hexString copy];
 
-    RNVoipPushNotificationManager *voipPushManager = [RNVoipPushNotificationManager allocWithZone: nil];
+    RNVoipPushNotificationManager *voipPushManager = [RNVoipPushNotificationManager sharedInstance];
     [voipPushManager sendEventWithNameWrapper:RNVoipPushRemoteNotificationsRegisteredEvent body:_lastVoipToken];
 }
 
@@ -175,7 +176,7 @@ + (void)didReceiveIncomingPushWithPayload:(PKPushPayload *)payload forType:(NSSt
     RCTLog(@"[RNVoipPushNotificationManager] didReceiveIncomingPushWithPayload payload.dictionaryPayload = %@, type = %@", payload.dictionaryPayload, type);
 #endif
 
-    RNVoipPushNotificationManager *voipPushManager = [RNVoipPushNotificationManager allocWithZone: nil];
+    RNVoipPushNotificationManager *voipPushManager = [RNVoipPushNotificationManager sharedInstance];
     [voipPushManager sendEventWithNameWrapper:RNVoipPushRemoteNotificationReceivedEvent body:payload.dictionaryPayload];
 }