Hey guys, so I am getting these inconsistent errors when running my program, only about 50% of the time do these errors occur, and at seemingly different points of my program. Here is the console output:
2011-05-11 14:22:03.926 Parking[20611:1903] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSMutableArray insertObject:atIndex:]: attempt to insert nil object at 10'
*** Call stack at first throw:
(
0 CoreFoundation 0x011afbe9 __exceptionPreprocess + 185
1 libobjc.A.dylib 0x013045c2 objc_exception_throw + 47
2 CoreFoundation 0x011a97f1 -[__NSArrayM insertObject:atIndex:] + 225
3 CoreFoundation 0x011a4c44 -[__NSArrayM addObject:] + 68
4 Parking 0x000182fd -[DataLoader loadOverlaysFromStore] + 1521
5 Parking 0x00017b76 -[DataLoader main] + 64
6 Foundation 0x00c5ebd2 -[__NSOperationInternal start] + 747
7 Foundation 0x00c5e826 ____startOperations_block_invoke_2 + 106
8 libSystem.B.dylib 0x9488c024 _dispatch_call_block_and_release + 16
9 libSystem.B.dylib 0x9487e2f2 _dispatch_worker_thread2 + 228
10 libSystem.B.dylib 0x9487dd81 _pthread_wqthread + 390
11 libSystem.B.dylib 0x9487dbc6 start_wqthread + 30
)
terminate called after throwing an instance of 'NSException'
And:
2011-05-11 14:16:45.171 Parking[20500:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSMutableArray insertObject:atIndex:]: attempt to insert nil object at 2'
*** Call stack at first throw:
(
0 CoreFoundation 0x011afbe9 __exceptionPreprocess + 185
1 libobjc.A.dylib 0x013045c2 objc_exception_throw + 47
2 CoreFoundation 0x011a97f1 -[__NSArrayM insertObject:atIndex:] + 225
3 CoreFoundation 0x011a4c44 -[__NSArrayM addObject:] + 68
4 Parking 0x00012887 -[CoreDataSingleton getParkingLotTitlesForPermits:] + 1030
5 Parking 0x00004891 -[ParkingMapViewController sortLotsIntoSetsAccordingToPermitsAccepted] + 616
6 Parking 0x00006317 -[ParkingMapViewController viewDidLoad] + 1474
7 UIKit 0x000fc65e -[UIViewController view] + 179
8 UIKit 0x000faa57 -[UIViewController contentScrollView] + 42
9 UIKit 0x0010b201 -[UINavigationController _computeAndApplyScrollContentInsetDeltaForViewController:] + 48
10 UIKit 0x00109831 -[UINavigationController _layoutViewController:] + 43
11 UIKit 0x0010ab4c -[UINavigationController _startTransition:fromViewController:toViewController:] + 524
12 UIKit 0x00105606 -[UINavigationController _startDeferredTransitionIfNeeded] + 266
13 UIKit 0x0021de01 -[UILayoutContainerView layoutSubviews] + 226
14 QuartzCore 0x01a15451 -[CALayer layoutSublayers] + 181
15 QuartzCore 0x01a1517c CALayerLayoutIfNeeded + 220
16 QuartzCore 0x01a15088 -[CALayer layoutIfNeeded] + 111
17 UIKit 0x000fdb5f -[UIViewController window:willAnimateRotationToInterfaceOrientation:duration:] + 587
18 UIKit 0x000768e9 -[UIWindow _setRotatableClient:toOrientation:updateStatusBar:duration:force:] + 4347
19 UIKit 0x002f5948 -[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:] + 1053
20 UIKit 0x00100982 -[UIViewController presentModalViewController:withTransition:] + 3151
21 Parking 0x0000b104 -[SampleHomeScreen appButtonTapped:] + 124
22 UIKit 0x0004ea6e -[UIApplication sendAction:to:from:forEvent:] + 119
23 UIKit 0x000dd1b5 -[UIControl sendAction:to:forEvent:] + 67
24 UIKit 0x000df647 -[UIControl(Internal) _sendActionsForEvents:withEvent:] + 527
25 UIKit 0x000de1f4 -[UIControl touchesEnded:withEvent:] + 458
26 UIKit 0x000730d1 -[UIWindow _sendTouchesForEvent:] + 567
27 UIKit 0x0005437a -[UIApplication sendEvent:] + 447
28 UIKit 0x00059732 _UIApplicationHandleEvent + 7576
29 GraphicsServices 0x01424a36 PurpleEventCallback + 1550
30 CoreFoundation 0x01191064 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 52
31 CoreFoundation 0x010f16f7 __CFRunLoopDoSource1 + 215
32 CoreFoundation 0x010ee983 __CFRunLoopRun + 979
33 CoreFoundation 0x010ee240 CFRunLoopRunSpecific + 208
34 CoreFoundation 0x010ee161 CFRunLoopRunInMode + 97
35 GraphicsServices 0x01423268 GSEventRunModal + 217
36 GraphicsServices 0x0142332d GSEventRun + 115
37 UIKit 0x0005d42e UIApplicationMain + 1160
38 Parking 0x00002424 main + 102
39 Parking 0x000023b5 start + 53
)
terminate called after throwing an instance of 'NSException'
I have run through it with a debugger and have not been able to determine at which point of my program it fails at, however, I do have an inkling it may be within this new section of code I wrote (tossed in additional retains here and there to help this error-will deal with releasing later):
-(id)initWithFunction:(LoaderFunc)func withDelegate:(id)delegate setRestricted:(NSSet *)restricted
setA:(NSSet *)A setC:(NSSet *)C setL:(NSSet *)L {
if (self = [super init]) {
self.addedOverlays = [[NSMutableArray alloc] init];
self.addedAnnotations = [[NSMutableArray alloc] init];
self.overlayRegions = [[NSMutableArray alloc] init];
self.loaderFunc = func;
self.DLDelegate = delegate;
return self;
}
return nil;
}
//...
-(void)loadOverlaysFromStore {
NSLog(@"DataLoader.m loadOverlaysFromStore");
//NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
NSDictionary *permits;
permits = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"0",@"0",@"0",nil] forKeys:[NSArray arrayWithObjects:@"A",@"C",@"L",nil]];
NSSet *setOfRestrictedLots = [[NSSet setWithArray:[[CoreDataSingleton sharedManager] getParkingLotsForPermits:permits]] retain];
NSMutableArray *arrayOfRestrictedLotTitles = [[NSMutableArray alloc] init];
for (ParkingLot *l in [setOfRestrictedLots allObjects]) {
[arrayOfRestrictedLotTitles addObject:[[l lotName]retain]];
}
permits = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"1",@"0",@"0",nil] forKeys:[NSArray arrayWithObjects:@"A",@"C",@"L",nil]];
NSSet *setOfALots = [[NSSet setWithArray:[[CoreDataSingleton sharedManager] getParkingLotsForPermits:permits]] retain];
NSMutableArray *arrayOfALotTitles = [[NSMutableArray alloc] init];
for (ParkingLot *l in [setOfALots allObjects]) {
[arrayOfALotTitles addObject:[[l lotName]retain]];
}
permits = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"1",@"1",@"0",nil] forKeys:[NSArray arrayWithObjects:@"A",@"C",@"L",nil]];
NSSet *setOfCLots = [[NSSet setWithArray:[[CoreDataSingleton sharedManager] getParkingLotsForPermits:permits]] retain];
NSMutableArray *arrayOfCLotTitles = [[NSMutableArray alloc] init];
for (ParkingLot *l in [setOfCLots allObjects]) {
[arrayOfCLotTitles addObject:[[l lotName]retain]];
}
permits = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"1",@"1",@"1",nil] forKeys:[NSArray arrayWithObjects:@"A",@"C",@"L",nil]];
NSSet *setOfLLots = [[NSSet setWithArray:[[CoreDataSingleton sharedManager] getParkingLotsForPermits:permits]] retain];
NSMutableArray *arrayOfLLotTitles = [[NSMutableArray alloc] init];
for (ParkingLot *l in [setOfLLots allObjects]) {
[arrayOfLLotTitles addObject:[[l lotName]retain]];
}
[addedOverlays addObject:setOfRestrictedLots];
[addedOverlays addObject:setOfALots];
[addedOverlays addObject:setOfCLots];
[addedOverlays addObject:setOfLLots];
for (NSSet* set in addedOverlays) {
for (ParkingLot *lot in [set allObjects]) {
ParkingRegionOverlay *regionPolygon = [[ParkingRegionOverlay alloc] initWithPoints:[lot overlayCoordPoints]
andTitle:[lot lotName]
setRestricted:[NSSet setWithArray:arrayOfRestrictedLotTitles]
setA:[NSSet setWithArray:arrayOfALotTitles]
setC:[NSSet setWithArray:arrayOfCLotTitles]
setL:[NSSet setWithArray:arrayOfLLotTitles]];
[overlayRegions addObject:regionPolygon];
[regionPolygon release];
}
}
}//loadOverlays
Any help greatly appreciated. Thanks!
So I figured it out. Remember how I said it occurred only about 50% of the time? That was a HUGE hint by the way as I had some code that retrieved data from my Core Data Store that was accessed in two ways. I had modified my code to have a background thread access that method but forgot to remove the call to it from a portion of the code where the main thread operates. Thus there would be race conditions in accessing the data, and I am not too sure why it would result in obtaining a nil value in some cases, but removing the call to that function from the main thread rectified the problem.