Exc bad access after populating NSMutableArray with custom class extending CLPlacemark

Question

I have a PlaceAnnotation class that I fill into an NSMutableArray. In viewDidLoad, i initiate ihatethis

_ihatethis = [[NSMutableArray alloc]init];

I use a MKLocalSearchCompletionHandler to search. And handle the mapitems like this:

for (MKMapItem *mapItem in [response mapItems]){

     PlaceAnnotation *place = [[PlaceAnnotation alloc] init];
     [place assignTitle:[[mapItem placemark] name];

     [_ihatethis addObject:place];
}

[_ihatethis removeObjectAtIndex:2]; /*BAD ACCESS HERE*/
[_tableView reloadData];

This is my PlaceAnnotation.h file

@interface PlaceAnnotation : CLPlacemark <MKAnnotation>

@property (nonatomic, assign) CLLocationCoordinate2D coordinate;
@property (nonatomic, readonly, copy) NSString *title;
@property (nonatomic) NSDictionary* dict;
//@property (nonatomic) NSURL *url;
@property (nonatomic) NSString *phoneNum;
@property (readonly) BOOL selected;

-(void)assignTitle:(NSString *)newTitle;
-(void)assignSelected:(BOOL) boolVal;

This is my PlaceAnnotation.m file

#import "PlaceAnnotation.h"

@interface PlaceAnnotation ()

@property (readwrite) NSString *title;
@property (readwrite) BOOL selected;

@end

@implementation PlaceAnnotation

-(void) assignTitle:(NSString *)newTitle {
    if ( ![newTitle isEqualToString:[self title]]){
        self.title = newTitle;
    }
}

-(void) assignSelected:(BOOL)boolVal{
    self.selected = boolVal;
}

@end


@end

This is my first post, I have read a ton of answers that responded to exc_bad_access questions and I cannot figure this out. So I think that somehow the placeannotations are getting forgotten and released. So when i go to delete is later it is gone. I really am confused and angry.

How's `_ihatethis` declared? And b.t.w. it should be `_iHateThis`. In Objective-C we're quite strict about style. — Nikolai Ruhe, Nov 25 '13 at 22:13
Is the declaration `_ihatethis` being initialized before running through your loop? Second: does your loop have at least 3 objects being added? (`[_ihatethis removeObjectAtIndex:2]` is removing the third object in your array). — Matt, Nov 25 '13 at 22:15
You showed how `_ihatethis`is being initialized, but not how it is declared (e.g. `NSMutableArray *_ihatethis` or `NSArray *_ihatethis`). If it's declared as the latter, you're going to have a bad time. — Matt, Nov 25 '13 at 22:24
@Matt Declaring the array `NSArray` would trigger compiler warnings, not a mach (runtime) exception. — Nikolai Ruhe, Nov 25 '13 at 22:33
What about the differences between the property `title` in the interface versus the interface extension? Is copying still occurring when calling the method `-assignTitle:`? Or is the `title` creating a strong reference to `newTitle`? — Matt, Nov 25 '13 at 22:38
Sorry, i switch it after getting frustrated. it is a property of the view, declared " @property NSMutableArray *ihatethis. I am using ARC. dreamlax, i dont know if it is some thing wrong with xcode 5. — William Franklin Katz, Nov 25 '13 at 23:14
Matt, the title is readonly, because that is how it is in CLPlacemark — William Franklin Katz, Nov 25 '13 at 23:16
@dreamlax , you're right. I thought it could be something with xcode 5 because this worked in xcode 4. But it ended up being a CLPlacemark issue so I updated the title. Thanks! — William Franklin Katz, Dec 02 '13 at 19:59

score 1 · Answer 1 · answered Nov 25 '13 at 22:24

1

If the crash really is in this line [_ihatethis removeObjectAtIndex:2]; and it's a EXC_BAD_ACCESS then there are two possibilities:

_ihatethis is pointing to a broken array (unlikely, if the loop went through).
An object in the array has been overreleased or has broken memory management in its dealloc method.

answered Nov 25 '13 at 22:24

Nikolai Ruhe

81,520
17
180
200

I am using ARC and the only objects i am using are PlaceAnnotation, a class i made to extend CLPlacemark. Do you have any ideas of where I should look for this broken memory? – William Franklin Katz Nov 25 '13 at 22:48

score 0 · Answer 2 · answered Nov 25 '13 at 22:19

0

It may be that you're trying to remove an item at an index greater than the array's count. Try to output the count just before [_ihatethis removeObjectAtIndex:2];, like this:

`
NSLog(@"count: %d", [_ihatethis count]);
[_ihatethis removeObjectAtIndex:2]; /*BAD ACCESS HERE*/
`

If the count is smaller than 3, then you're trying to remove an object at an index outside the array's bounds.

answered Nov 25 '13 at 22:19

Out of bounds access would not result in an EXC_BAD_ACCESS but an Objective-C exception with a proper error message. – Nikolai Ruhe Nov 25 '13 at 22:20

score 0 · Accepted Answer · answered Dec 02 '13 at 17:38

0

I changed this

@interface PlaceAnnotation : CLPlacemark <MKAnnotation>

to this

@interface PlaceAnnotation : NSObject <MKAnnotation>

so i guess the problem was with the dealloc of CLPlacemark. Thanks

answered Dec 02 '13 at 17:38

William Franklin Katz

46
5

It would appear the CLPlacemark is the problem. I found that simply new'ing CLPlacemark will cause an EXC_BAD_ACCESS at the end of the method with ARC. I haven't been able to figure out why, but it sure makes it tough extend CLPlacemark and then test them. – David Potter May 16 '14 at 19:08

Exc bad access after populating NSMutableArray with custom class extending CLPlacemark

3 Answers3

Linked