ios/objective c/singleton: Storing userid in session variable

Question

I defined an NSInteger in a singleton (for userid) and access it in another class. However, while I have managed to get rid of error messages so it builds, the app crashes when

Answer 1

Firstly, I recommend you follow this idiom for creating a thread safe singleton.

+ (Singleton *)sharedSettings{

    static Singleton *singleton;
    static dispatch_once_t onceToken;

    dispatch_once(&onceToken, ^{

        singleton = [[self alloc] initPrivate];

    });

    return singleton;

}

- (instancetype)initPrivate{

    self = [super init];
    if(!self) return nil;


    return self;

}

Also, NSInteger is not an object. It is a typedef for a primitive long. So remove the object pointer.

typedef long NSInteger;

You seem to be confusing NSInteger with the NSNumber wrapper. Take a look at the docs for NSNumber.