Question

Assume

typedef void (^MyResponseHandler) (NSError *error);
@property (strong, nonatomic) MyResponseHandler ivarResponseHandler;
synthesize ivarResponseHandler = _ivarResponseHandler;

- (void)myMethod:(MyResponseHandler)responseHandler
{
    self.ivarResponseHandler = responseHandler;
    ...
}

Is the assignment to the ivar through the @property correct? I know that in manual memory management you would have needed self.ivarResponseHandler = [responseHandler copy]; to make sure the block was copied from the stack to the heap. But watching Session 322 – Objective-C Advancements in Depth (minute 25) from WWDC 2011, the speaker says that ARC automatically handles the assignment of a block to an ivar. I just wanted to make sure.

Answer 1

bearMountain,

The easiest way to ensure the block is copied is to, in fact, set the @property to use copy. As in:

@property (copy, nonatomic) MyResponseHandler ivarResponseHandler;

It does everything you need.

Andrew