I need to store weak references to objects in an NSArray, in order to prevent retain cycles. I'm not sure of the proper syntax to use. Is this the correct way?
Foo* foo1 = [[Foo alloc] init];
Foo* foo2 = [[Foo alloc] init];
__unsafe_unretained Foo* weakFoo1 = foo1;
__unsafe_unretained Foo* weakFoo2 = foo2;
NSArray* someArray = [NSArray arrayWithObjects:weakFoo1, weakFoo2, nil];
As Jason said, you can't make
NSArray store weak references. The easiest way to implement Emile's suggestion of wrapping an object inside another object that stores a weak reference to it is the following:
NSValue *value = [NSValue valueWithNonretainedObject:myObj]; [array addObject:value];
Another option: a category that makes
NSMutableArray optionally store weak references.
Note that these are "unsafe unretained" references, not self-zeroing weak references. If the array is still around after the objects are deallocated, you'll have a bunch of junk pointers.