NSFetchResult

He is using the _fetchedResultsController because we are creating a customized getter for the property. Xcode will create setters and getters for properties by default, however we always have the option to override the default and implement our own setter/getter.

The property does not always have to be declared in the header file. It only needs to be declared in the header file when it is a public property. In this case, we do not want/need the fetchedResultsController to be accessible outside of this specific object. Thus declaring a property in the implementation file makes it private to that object only.

Does this help?

i stumbled on the same problem but mine is even trickier ( or so I think): when customizing the getter method, if i dont use the variable with the underscore, but use a newly created one as follows:

-(NSFetchedResultsController *)fqcontrol{ if (_fqcontrol) { return _fqcontrol;} else{ NSFetchRequest *fq=[self getFq]; AppDelegate *maindelegate=[[UIApplication sharedApplication]delegate]; NSManagedObjectContext *context=maindelegate.managedObjectContext;

    NSFetchedResultsController *fqcontrol=[[NSFetchedResultsController alloc]initWithFetchRequest:fq managedObjectContext:context sectionNameKeyPath:nil cacheName:nil];

    fqcontrol.delegate=self;
    return fqcontrol;

}

}

then ALL I GET IS A BLANK TABLE. but once I switch back to underscore way, it totally works. I know the previous one is not efficient and such, but I think all that getter method cares is to return a controlling regardless of its original name, why underscore is necessary for this to work?

Hello Jack...

I had to think about this for a while... When you refer to the fqcontrol with out the under bar the compiler is looking to the object instead of a specific instance variable of the object (_fqcontrol).