Re: new to cocoa
Re: new to cocoa
- Subject: Re: new to cocoa
- From: Jens Alfke <email@hidden>
- Date: Fri, 14 May 2010 09:38:40 -0700
On May 11, 2010, at 1:36 PM, Alejandro Marcos Aragón wrote:
I'm new to Cocoa, and I couldn't find information about an error
that I'm getting on the web. I'm trying to create an
NSMutableDictionary where the keys are of type UIButton*:
Sounds like you're trying to associate data values with buttons. The
easiest way to do this is to use the control's existing 'tag'
property, which lets you store an arbitrary integer value. [Actually
I'm not certain that UIKit controls have tags; their corresponding
AppKit classes in Mac OS do.]
If you need to store a non-integer value, or have to use a dictionary
for some other reason, you can use [NSValue valueWithPointer: button]
to create a value object wrapping a pointer to your button. Those
values can be used as dictionary keys. To unwrap one, use (UIButton*)
[value pointerValue]. Just make sure to remove the associated key
object when a button is deleted, otherwise it's a dangling pointer to
a deleted object and will cause a crash if you try to use that button
pointer again.
—Jens_______________________________________________
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| | >new to cocoa (From: Alejandro Marcos Aragón <email@hidden>) |