ReachabilityUpdater.h

//
//  ReachabilityUpdater.h
//
//
//  Created by Gregg Jaskiewicz on 10/04/2018.
//  Copyright © 2018 . All rights reserved.
//

#import <Foundation/Foundation.h>

typedef void (^ReachabilityUpdateCallback)(BOOL networkReachable);

@interface ReachabilityUpdater : NSObject

- (instancetype __nullable)init __attribute__((unavailable("You cannot create a ReachabilityUpdater instance through init - please initWithUpdateCallback:")));
- (instancetype _Nonnull)initWithUpdateCallback:(ReachabilityUpdateCallback __nonnull)callback NS_DESIGNATED_INITIALIZER;

@end

ReachabilityUpdater.m

//
//  ReachabilityUpdater.m
//
//
//  Created by Gregg Jaskiewicz on 10/04/2018.
//  Copyright © 2018 . All rights reserved.
//

#import "ReachabilityUpdater.h"
#import "Reachability.h"

@interface ReachabilityUpdater()

@property(nonatomic, copy) ReachabilityUpdateCallback callback;
@property(nonatomic, strong) Reachability *reachability;

@end

@implementation ReachabilityUpdater

- (instancetype)initWithUpdateCallback:(ReachabilityUpdateCallback)callback {
    self = [super init];

    if (self != nil) {
        _callback = [callback copy];

        self.reachability = [Reachability reachabilityForInternetConnection];
        [self updateWithCurrentReachability:self.reachability.currentReachabilityStatus];

        // subscribe to notifications
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(updated:) name:kReachabilityChangedNotification object:nil];

        [self.reachability startNotifier];
    }

    return self;
}

- (void)dealloc {
    NSLog(@"reachability updater going away");
}

- (void)updateWithCurrentReachability:(NetworkStatus)currentReachability {
    BOOL wifiReachable = (currentReachability == ReachableViaWiFi);
    BOOL wanReachable = (currentReachability == ReachableViaWWAN);

    BOOL networkReachable = (wifiReachable == YES) || (wanReachable == YES);

    self.callback(networkReachable);
}

- (void)updated:(NSNotification *)notification {
    if ([notification.object isKindOfClass:[Reachability class]] == YES) {
        Reachability *reachability = (Reachability *)notification.object;
        NetworkStatus currentReachability = reachability.currentReachabilityStatus;
        [self updateWithCurrentReachability:currentReachability];
    } else {
        NSLog(@"incorrect reachability?");
    }
}

@end