> On Sep 24, 2016, at 8:11 AM, Patrick J. Collins 
> <[email protected]> wrote:
> 
> When I run this, I get 0 instead of 123.  

Right; you’ve created a new, different ivar in the subclass, which just happens 
to have the same name.

> Is there a way I can get access to the _wut ivar in the base class

Yes, by using the power of <objc/runtime.h>. This is a super-powerful API that 
lets you open up and mess with classes like Legos. You can find the ivars and 
methods, modify variables, even create and remove methods and create new 
classes.

Looks like the function you’ll need is object_setInstanceVariable.

Obviously this great power should be used responsibly. I’d only recommend doing 
this as a last resort, if there’s no way to modify the library yourself. Also, 
if it's a system library, be careful because the library’s implementation could 
change in any future OS release and invalidate your hack, breaking your app.

—Jens
 _______________________________________________
Do not post admin requests to the list. They will be ignored.
Objc-language mailing list      ([email protected])
Help/Unsubscribe/Update your Subscription:
https://lists.apple.com/mailman/options/objc-language/archive%40mail-archive.com

This email sent to [email protected]

Reply via email to