Singleton in iOS Objective C doesn't prevent more than one instance

Question

I know there are several threads on this, but none answer my questions.

I\'ve implemented my singleton class like this (being aware of the controversy about singleto

Answer 1

This works for me :

static DataModel *singleInstance;

+ (DataModel*)getInstance{
    if (singleInstance == nil) {
        singleInstance = [[super alloc] init];
    }
    return singleInstance;
}

You can call it with

_model = [DataModel getInstance];