"EXC_BAD_ACCESS" when switch too fast between an tableView and a mapView

Question

I have a tableView with an button to push a mapView. The push and back actions generally work fine. If I switch quickly between these two views, "EXC_BAD_ACCESS" error will appear.

MapViewController.m

- (void)viewDidLoad
{
[super viewDidLoad];
self.mapView.delegate = self;    

UIButton *btnL = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 40.0, 40.0)];
[btnL setImage:[UIImage imageNamed:@"back.png"] forState:UIControlStateNormal];
[btnL addTarget:self.navigationController  action:@selector(popViewControllerAnimated:) forControlEvents:UIControlEventTouchDown];
self.navigationItem.leftBarButtonItem = [[[UIBarButtonItem alloc] initWithCustomView:btnL] autorelease];
[btnL release];

self.whereAmIAnnotation = [[[WhereAmIAnnotation alloc] init] autorelease];

if (!self.mapView || !self.whereAmIAnnotation) {
    NSLog(@"mapview : %@", self.mapView);
    NSLog(@"whereAmIAnnotation : %@",self.whereAmIAnnotation);
 // will never enter in to here
}

[self.mapView addAnnotation:self.whereAmIAnnotation];

}

If I comment [self.mapView addAnnotation:self.whereAmIAnnotation]; , there is no "EXC_BAD_ACCESS" anymore.

Any answers and comments will be appreciated. Thanks in advance!

Edit 2

main.m

#import <UIKit/UIKit.h>

#import "AppDelegate.h"

int main(int argc, char *argv[])
{
@autoreleasepool {
    return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
 // "EXC_BAD_ACCESS" error message shows here
}
}

Edit 3:

the whereAmIAnnotation is declared here:

MapViewController.m

@interface AddrCoordinateAdjustMapViewController()

@property (retain) WhereAmIAnnotation *whereAmIAnnotation;

@end
@implementation MapViewController
@synthesize whereAmIAnnotation;

Edit 4:

Error message is as following:

2012-07-30 15:56:19.735 myApp[13584:707] *** -[MapViewController respondsToSelector:]: message sent to deallocated instance 0x10195e80

It usually crashes when i switch back to the tableView while the annotationView is dropping.

Did you try to insert a breakpoint and check value of self.mapView and self.whereAmIAnnotation? Try to do a simple check: if(self.mapView && self.whereAmIAnnotation)... — Marco Pace, Jun 05 '12 at 08:17
have you tried to debug? Put an exception break point to see which line the crash is happening? — Krishnabhadra, Jun 05 '12 at 08:17
How do you set self.mapView? Is it an IBOutlet? Do you do it by code. Can you show how you set and release it? — iTukker, Jun 05 '12 at 08:32
@iTukker It is an IBOutlet. I have never release it, as it is will be autorelease. — lu yuan, Jun 05 '12 at 08:45
@Krishnabhadra I tried. It crashed in the main.m. So i can't figure out which ivar it refers to. — lu yuan, Jun 05 '12 at 08:46
@luyuan I still think you didn't understand what I referred by exception breakpoint..http://stackoverflow.com/questions/4961770/run-stop-on-objective-c-exception-in-xcode-4 — Krishnabhadra, Jun 05 '12 at 08:51
check the header (.h file) and see whether your whereAmIAnnotation property is "assign" — xingzhi.sg, Jun 05 '12 at 08:59

score 3 · Accepted Answer · answered Jul 30 '12 at 05:08

3

Have you removed yourself as delegate of the mapview?

self.mapview.delegate = nil;

try removing it at viewWilldisappear or whenever you consider necessary as you might need it later if you have pushed a view controller and will return to the view later.

In a nutshell, remove it when your view cannot respond to the delegate which is why you got the EXC_BAD_ACCSS. it sent a message to your view but it was already released from memory.

answered Jul 30 '12 at 05:08

Dan1one

1,288
8
13

Thank you very much. It really hits the point! I should set the delegate of mapview to nil while leaving the mapview. – lu yuan Jul 30 '12 at 08:16

score 1 · Answer 2 · answered Jun 05 '12 at 09:03

1

Do you release and set to nil all your IBOutlets in the viewDidUnload? So at least you should do:

- (void)viewDidUnload {
   self.mapView = nil;
   [super viewDidUnload];
}

Generally in ViewDidUnload you should release and set to nil, any view objects that are created from a Nib file or allocated in your ViewDidLoad method

answered Jun 05 '12 at 09:03

iTukker

2,083
2
16
16

yes, it should be set to nil in viewDidUnload, but the error still be there:) – lu yuan Jun 05 '12 at 09:09

score 0 · Answer 3 · answered Jun 05 '12 at 08:20

0

I would suggest to check whether self.whereAmIAnnotation isnt already released by at the time you add it to mapView. That might be one reason for the BAD_ACCESS you receive.

answered Jun 05 '12 at 08:20

mooonli

2,355
4
23
32

score 0 · Answer 4 · answered Nov 18 '14 at 08:39

0

I had similar problem and my solution was to remove all overlays from the map before popping controller from UINavigationController. I was using OpenStreetMap.

answered Nov 18 '14 at 08:39

ArturOlszak

2,653
2
21
20

"EXC_BAD_ACCESS" when switch too fast between an tableView and a mapView

4 Answers4

Linked