CoreData crash while saving after setting value for NSManagedObject's property

I have a problem with saving CoreData. Main 3 things to remember:

1. I'm using NSFetchResultsController to populate my UITableView with data from CoreData
2. I'm lazy downloading images to show them in cells.
3. When downloading of icon ends I converta image data to base64 string and save that string in CoreData.

Problem is that when I try to save CoreData changes after receving icons I get crash. When I commented part of code re开发者_C百科sponsible for making changes to NSManagedObject everything worked fine, but I want to know how can I save that objects without crash.

This is where I update NSManagedObject after downloading icon:

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    if (self.activeDownload && [self.activeDownload length]>0) {
        NSString* base64 = [self.activeDownload base64Encoding]; // converting data to base64
        NSError* error= nil;
        Offer* offerDB2 = [self.offer offerObject]; // Offer is NSManagedObject subclass of my Entity
        if (offerDB2) {
            [offerDB2 setImageData:base64]; // Setting property value (if commented -> no crash)    
            [CoreDataHandler save]; // This is where App crashes
        }
    }
    self.activeDownload = nil;
    self.imageConnection = nil;
    [IconDownloader doNext];
}

Now Offer class

#import <CoreData/CoreData.h>

@interface Offer :  NSManagedObject  
{
}

@property (nonatomic, retain) NSString * bigInfo;
@property (nonatomic, retain) NSNumber * categoryID;
@property (nonatomic, retain) NSNumber * databaseID;
@property (nonatomic, retain) NSNumber * deleted;
@property (nonatomic, retain) NSString * descriptionString;
@property (nonatomic, retain) NSNumber * endDate;
@property (nonatomic, retain) NSString * extendedInfo;
@property (nonatomic, retain) NSNumber * offerType;
@property (nonatomic, retain) NSString * photoLink;
@property (nonatomic, retain) NSString * physicalUnit;
@property (nonatomic, retain) NSString * shopName;
@property (nonatomic, retain) NSNumber * size;
@property (nonatomic, retain) NSString * sizeUnit;
@property (nonatomic, retain) NSString * smallInfo;
@property (nonatomic, retain) NSNumber * startDate;
@property (nonatomic, retain) NSNumber * unitPrice;
@property (nonatomic, retain) NSString * unitPriceName;
@property (nonatomic, retain) NSString * imageData;

@end

#import "Offer.h"

@implementation Offer 

@dynamic bigInfo;
@dynamic categoryID;
@dynamic databaseID;
@dynamic deleted;
@dynamic descriptionString;
@dynamic endDate;
@dynamic extendedInfo;
@dynamic offerType;
@dynamic photoLink;
@dynamic physicalUnit;
@dynamic shopName;
@dynamic size;
@dynamic sizeUnit;
@dynamic smallInfo;
@dynamic startDate;
@dynamic unitPrice;
@dynamic unitPriceName, imageData;

-(NSNumber*)sectionNumber{
    return self.offerType;
}

@end

CrashLog looks like that:

*** -[NSCFType evaluateWithObject:]: unrecognized selector sent to instance 0x4354210
Program received signal:  “EXC_BAD_ACCESS”.

#0  0x32668ec0 in objc_msgSend
#1  0x32de2b5e in __CFExceptionProem
#2  0x32de2bcc in -[NSObject doesNotRecognizeSelector:]
#3  0x32d67b18 in ___forwarding___
#4  0x32d5e840 in __forwarding_prep_0___
#5  0x30537cbe in -[NSFetchedResultsController(PrivateMethods) _objectInResults:]
#6  0x30538d16 in -[NSFetchedResultsController(PrivateMethods) _preprocessUpdatedObjects:insertsInfo:deletesInfo:updatesInfo:sectionsWithDeletes:newSectionNames:treatAsRefreshes:]
#7  0x3053aa2c in -[NSFetchedResultsController(PrivateMethods) _managedObjectContextDidChange:]
#8  0x33f765d8 in _nsnote_callback
#9  0x32d9e510 in _CFXNotificationPostNotification
#10 0x33f741b2 in -[NSNotificationCenter postNotificationName:object:userInfo:]
#11 0x304b4388 in -[NSManagedObjectContext(_NSInternalNotificationHandling) _postObjectsDidChangeNotificationWithUserInfo:]
#12 0x3050768a in -[NSManagedObjectContext(_NSInternalChangeProcessing) _createAndPostChangeNotification:withDeletions:withUpdates:withRefreshes:]
#13 0x3049c2b0 in -[NSManagedObjectContext(_NSInternalChangeProcessing) _processRecentChanges:]
#14 0x304cb186 in -[NSManagedObjectContext save:]

Possible problems:

1. CoreData while saving can deal with lots of data. Those images converted to base64 can contain lots of characters.
2. Lines #5,#6,#7 say something about NSFetchResultsController.

SOLVED:

I simply released NSPredicate wchich was autoreleased object, so after saveing CoreDatra my NSFetchResultsController wanted to update its data, everuthing crashed.

---

You Havent Clear How You Have Create The Object Of Your Bean(NowOffer) Ithink There Is Mistake Create like Given Below

NowOffer objBean = (NowOffer *)[NSEntityDescription insertNewObjectForEntityForName:@"NowOffer" inManagedObjectContext:appDelegate.managedObjectContext];

Hope You Will Get Your Solutin........