Question

Sorry about this silly question. I’m trying to learn objc and I’m unable to do a simple sum between 2 int values… In fact problem is before the sum.

I have an object that have an instance variable defined as a NSNumber and it’s defined as a property as follows:

@interface MyObj : NSObject {
   NSNumber *count;
}
@property (readwrite, assign) NSNumber *count;
@end

@implementation MyObj
@synthetize count;
@end

Then I have a class that will consume MyObj:

- (void)total:(MyObj *)mobj {
   int count = [mobj.count intValue];

   NSLog(@"%@", mobj.count);
   NSLog(@"%@", count);

   int total = 10 + count;
   NSLog(@"%@", total);
}

The first NSLog prints the mobj.count nicely (let’s say 5), but the second one, throws an EXC_BAD_ACCESS. And of course the program never reachs the sum.

So, what I’m doing wrong? I’m trying to convert it to a int based on this post.

TIA,

Bob

Answer 1

The specifier %@ is for printing Obj-C objects, and it asks for the object’s -description. The count in your code is an int. Use %i for ints. Check out NSLog() Specifiers.