adding NSInteger object to NSMutableArray

Question

I have an NSMutableArray

@interface DetailViewController : UIViewController <UITableViewDelegate, UITableViewDataSource> {

NSMutableArray *reponses;
}
@property (nonatomic, retain) NSMutableArray *reponses;

@end

and i'm trying to add in my array NSInteger object:

@synthesize reponses;



NSInteger val2 = [indexPath row];
[reponses addObject:[NSNumber numberWithInteger:val2]];
NSLog(@"the array is %@ and the value is %i",reponses, val2);

it won't work the object was not added to the array, this is what console shows:

the array is (null) and the value is 2

Ferdy

Answer 1

You're not initializing your array, so it's still nil when you're trying to add to it.

self.responses = [NSMutableArray array];
//now you can add to it.

Hodson

Answer 2

@Omz: is right. Make sure you have the array allocated and initialized. Please check the following code

NSMutableArray *array = [[NSMutableArray alloc] init];
NSInteger num = 7;
NSNumber *number = [NSNumber numberWithInt:num];
[ar addObject:number];
NSLog(@"Array %@",array);

I have checked this and it works. If array is no longer needed make sure you release it.

Hines

for new folks (me), to convert NSNumber back to NSInteger (when retrieving information from the array), 'NSInteger num = [number integerValue];' (thank you 7KV7) – Corazoncorban

Answer 3

You have not initialized the responses array. In your code, may be viewDidLoad, do:

reponses = [[NSMutableArray alloc] init];

Then add the object to your array.

NSInteger val2 = [indexPath row];
[self.reponses addObject:[NSNumber numberWithInteger:val2]];

That should work.

Chromatolysis