Question

If I have the below property:

@property (nonatomic, retain) MyObject *theObject;

then if I want to create a new MyObject, do I:

self.theObject = [[MyObject alloc] init];

or:

self.theObject = [[[MyObject alloc] init] autorelease];

Answer 1

You have to use autorelease. If you don’t, the object will have a release count of two (one from alloc, one from the retain by the setter), so when the property is unset, it’ll be leaked.

This only applies to strong or retained and copy properties. Assigned and weak properties should just be assigned an alloc-initted object, since they don’t alter its reference count.