Re: With What does Apple Swizzle the IsA-pointer in KVO?

FROM : Sherm Pendley
DATE : Fri Nov 23 20:01:09 2007

On Nov 23, 2007, at 1:09 PM, Philip Mötteli wrote:

> In order to use KVO, you need to know this famous "key". The key is 
> the name of an instance variable


Not so:

- (id)foo {
   return bar;
}

This is a KVC-compliant accessor method for the key "foo", and 
doesn't rely on an instance variable named "foo".

> , which is an object's internal data. Every OOP book will tell you 
> that


You might want to re-read those books. One of the primary points of 
KVC is to disassociate public keys from private instance variables. 
Granted, a one-to-one mapping of keys to ivars is often the most 
convenient way to implement it, but it's definitely not a requirement.

sherm--

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