What is the strong property attribute

Question

I am using the Xcode beta for developers, and am noticing some subtle differences. Among them is a new attribute for declared properties.

@property(strong)IB         


        

Answer 1

A strong reference is a reference to an object that stops it from being deallocated. In other words it creates a owner relationship. Whereas previously you would do this:

**// Non-ARC Compliant Declaration
@property(retain) NSObject *obj;**

Under ARC we do the following to ensure a class instance takes an ownership interest a referenced object (i.e. so it cannot be deallocated until the owner is).

**// ARC Compliant Declaration
@property(strong) NSObject *obj;**