7
votes

Hi I'm getting crash,

when i'm trying to insert 1000 records into db in back ground, i'm getting following exception: CoreData: error: Serious application error. Exception was caught during Core Data change processing.
This is usually a bug within an observer of

NSManagedObjectContextObjectsDidChangeNotification. -[__NSCFSet addObject:]: attempt to insert nil with userInfo (null)2013-11-19 09:41:19.587 3pTalk[7487:907]

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFSet addObject:]: attempt to insert nil'

I used the code for inserting objexts

dispatch_queue_t myBackgroundQ = dispatch_queue_create("com.sample.addressbook", NULL);
// Could also get a global queue; in this case, don't release it below.
dispatch_time_t delay = dispatch_time(DISPATCH_TIME_NOW, NSEC_PER_SEC);
dispatch_after(delay, myBackgroundQ, ^(void){
    [self userAddressbook];
});
dispatch_release(myBackgroundQ);
[self performSelectorOnMainThread:@selector(startSyncLoader) withObject:nil waitUntilDone:YES];
2
What does the code look like that does the actual insert. It looks like you could be trying to add a nil object to a To-Many relationship or using a managedObjectContext on the wrong thread. - Duncan Groenewald
where is the code that inserts the data into the database? - J2theC

2 Answers

16
votes

Dont access same Database(Persistent Store Coordinator) from 2 threads(Main,Background) simultaneously with one context. This is not recommended. it causes App Crash.

create NSManagedContext Object and set persistentstoreCoordinator.

    dispatch_queue_t request_queue = dispatch_queue_create("com.xxx.ScsMethod", NULL);
    dispatch_async(request_queue, ^{
    NSPersistentStoreCoordinator *mainThreadContextStoreCoordinator = [context     persistentStoreCoordinator]; //
    NSManagedObjectContext *context = [[NSManagedObjectContext alloc] init]; // 
    [context setPersistentStoreCoordinator:mainThreadContextStoreCoordinator];}
2
votes

Are you accessing the database from two threads simultaneously?, using same context? That may be the reason. see this question

Problems Adding to NSMutableArray: attempt to insert nil object at 10