Exc Bad Access while unarchiving data from iCloud using UIDocument - iphone

Question

Hi i am using iCloud support for my application and using UIDocument for storage. I was able to save data to iCloud and fetch the same for first time. But when i deleted and reinstalled the app on device, the seems to crash with EXC BAD ACCESS while trying to unarchive data using NSKeyUnarchiver.
Code.
BuyerDocument.m // UIDocument Subclass
// Accessor for BuyerData
- (BuyerData *)data {
if (_data == nil) {
if (self.fileWrapper != nil) {
self.data = [self decodeObjectFromWrapperWithPreferredFilename:BUYER_FILENAME]; // BUYER_FILENAME = #"buyer.data"
} else {
self.data = [[BuyerData alloc] init];
}
}
return _data;
}
- (id)decodeObjectFromWrapperWithPreferredFilename:(NSString *)preferredFilename {
NSFileWrapper * fileWrapper = [self.fileWrapper.fileWrappers objectForKey:preferredFilename];
if (!fileWrapper) {
NSLog(#"Unexpected error: Couldn't find %# in file wrapper!", preferredFilename);
return nil;
}
if([fileWrapper isRegularFile]){
NSLog(#"is regular wrapper");
}
NSData * data = [fileWrapper regularFileContents];
NSLog(#"data %#",data); // This logs successfully
// NSLog(#"data bytes %#",[data bytes]) // This also causes app to crash.
NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data]; // App will crash here
return [unarchiver decodeObjectForKey:#"data"];
}
Loading BuyerDocument here.
- (void)loadDocAtURL:(NSURL *)fileURL {
// Open doc so we can read metadata
BuyerDocument * doc = [[BuyerDocument alloc] initWithFileURL:fileURL];
[doc openWithCompletionHandler:^(BOOL success) {
.......
BuyerData * data = doc.data;
....
[doc closeWithCompletionHandler:^(BOOL success) {
.....
}];
}
BuyerData.m
#define kVersionKey #"Version"
#define kNameKey #"Name"
- (void)encodeWithCoder:(NSCoder *)encoder {
[encoder encodeInt:1 forKey:kVersionKey];
[encoder encodeObject:self.name forKey:kNameKey];
}
- (id)initWithCoder:(NSCoder *)decoder {
[decoder decodeIntForKey:kVersionKey];
NSString *nameData = [decoder decodeObjectForKey:kNameKey];
// NSLog(#">>>>>>>>>>>>>>>>>>> %#",name); // This logs for first 2-3 files and then crash occurs
return [self initWithName:nameData];
}
As i said when i first added data everything ran fine, it was only after deleting and reinstalling that crash began to occur. Also first 3-4 names are fetched and displayed in tableview before this crash occurs.
Tried this but of no help
I am fairly new to UIDocument and NSCoding. So can't say much about them. But i guess some how the issue might be with linked to NSData getting lost or corrupted out there. Am i missing something basic and important here. What am i doing wrong?