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Re: Sending a msg. to a class



On Oct 25, 2007, at 2:35 PM, z wrote:


I'll appreciate someone to help me understand the problem and suggest solution.
I'm trying to send a msg. to Pawn1 thru Pawn16 classes, but it doesn't work from inside the loop.
Thanks.


- (IBAction)resetAll: (id)sender {

// 	[toPawn1 showYourself];  		//--- This works fine.
// 	.......
// 	[toPawn16 showYourself];

/ but the following generates a warning: 'NSMutableString' may not respond to '-showYourself'

for (i = 1; i <= 16; ++i) {
NSMutableString *str = [NSMutableString stringWithFormat: @"toPawn %i", i];
[ [str className] showYourself];
[str release];
}
}


1. You're not sending the showYourself method to the class, but to the object that is returned from the -className message, which is an NSString instance. That's why you're getting the warning. To get a class object from an NSString, you need to use NSClassFromString function.
2. You shouldn't release str, since you didn't alloc, retain or copy it. See the docs on memory management.


NSString* className = [NSString stringWithFormat:@"toPawn%i", i];
Class theClass = NSClassFromString(className);
[theClass showYourself];



Glen
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 >Sending a msg. to a class (From: "z" <email@hidden>)



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