Trying to find out Core Data Errors Error, and looking inside userInfo in NSError returned by MOC's save method.
iphone-core-data-unresolved-error-while-saving I am not able to make commends or raise questions due to my lack of points.
Can any one point out for me where following keys are defined in Apple Doc, NSValidationErrorObject, NSValidationErrorKey...etc?
My understanding is: if CoreData's Error code == NSValidationMultipleErrorsError, then NSError's userInfo(dictionary) will contain all detailed-single-error information, and all those detailed-single-error will be accessible from an Array stored under "NSDetailedErrorsKey" from userInfo.
I just don't see them (NSValidationErrorObject, NSValidationErrorKe...) in Core Data Constants Reference...??? Are they opaque ?
Thanks.
- (BOOL)saveData {
NSError *error;
if (![_sharedManagedObjectContext save:&error]) {
// If Cocoa generated the error...
NSString *message = nil;
if ([[error domain] isEqualToString:@"NSCocoaErrorDomain"]) {
// ...check whether there's an NSDetailedErrors array
NSDictionary *userInfo = [error userInfo];
if ([userInfo valueForKey:@"NSDetailedErrors"] != nil) {
// ...and loop through the array, if so.
NSArray *errors = [userInfo valueForKey:@"NSDetailedErrors"];
for (NSError *anError in errors) {
NSDictionary *subUserInfo = [anError userInfo];
subUserInfo = [anError userInfo];
// Granted, this indents the NSValidation keys rather a lot
// ...but it's a small loss to keep the code more readable.
NSLog(@"Core Data Save Error\n\n \
NSValidationErrorKey\n%@\n\n \
NSValidationErrorPredicate\n%@\n\n \
NSValidationErrorObject\n%@\n\n \
NSLocalizedDescription\n%@",
[subUserInfo valueForKey:@"NSValidationErrorKey"],
[subUserInfo valueForKey:@"NSValidationErrorPredicate"],
[subUserInfo valueForKey:@"NSValidationErrorObject"],
[subUserInfo valueForKey:@"NSLocalizedDescription"]);
}
}
// If there was no NSDetailedErrors array, print values directly
// from the top-level userInfo object. (Hint: all of these keys
// will have null values when you've got multiple errors sitting
// behind the NSDetailedErrors key.
else {
NSLog(@"Core Data Save Error\n\n \
NSValidationErrorKey\n%@\n\n \
NSValidationErrorPredicate\n%@\n\n \
NSValidationErrorObject\n%@\n\n \
NSLocalizedDescription\n%@",
[userInfo valueForKey:@"NSValidationErrorKey"],
[userInfo valueForKey:@"NSValidationErrorPredicate"],
[userInfo valueForKey:@"NSValidationErrorObject"],
[userInfo valueForKey:@"NSLocalizedDescription"]);
}
}
// Handle mine--or 3rd party-generated--errors
else {
NSLog(@"Custom Error: %@", [error localizedDescription]);
}
return NO;
}
return YES;
}
[1]: https://stackoverflow.com/questions/1283960/iphone-core-data-unresolved-error-while-saving
