Handy method for maintaining an Objective-C Singleton

Objective-C Singleton

+ (MyClass *)sharedInstance
{
    static MyClass *sharedInstance = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sharedInstance = [[MyClass alloc] init];
        // Do any other initialisation stuff here

    });
    return sharedInstance;
}