Objective-C declared @property attributes (nonatomic, copy, strong, weak)

Question

Can someone explain to me in detail when I must use each attribute: nonatomic, copy, strong, weak, and so on, for a decla

Answer 1

This link has the break down

http://clang.llvm.org/docs/AutomaticReferenceCounting.html#ownership.spelling.property

assign implies __unsafe_unretained ownership.

copy implies __strong ownership, as well as the usual behavior of copy semantics on the setter.

retain implies __strong ownership.

strong implies __strong ownership.

unsafe_unretained implies __unsafe_unretained ownership.

weak implies __weak ownership.