获取的物业在iOS5但不是iOS6的作品

Question

我的CoreData数据库中存在严重问题。我创建了2个表之间的一对多关系，并在包含所有唯一值的表上添加了一个Fetched属性。所有代码工作中的iOS 5，但在iOS 6中我收到以下errror预期：

2013年2月8日15：15：49.382 ArdsBoroughCouncil [16152：C07] *终止 应用程序由于未捕获的异常' NSUnknownKeyException'，原因： '[<_NSObjectID_48_0 0xb25c3b0> valueForUndefinedKey：]：该类别为 而非密钥tour_id的密钥值编码。 *第一掷调用堆栈：（0x31c7012 0x24a3e7e 0x324ffb1 0x1c445ed 0x1bb08db 0x1bb088d 0x1bceb17 0x1bfe746 0x21b74bb 0x21b7176 0x21b6e44 0x21b66f4 0x21b2d63 0x21b2a82 0x21b2850 0x21b2625 0x21b1e07 0x21b18f4 0x21b0a6d 0x21ae9c9 0x2201276 0x227b155 0x2201071 0x2880014 0x286fd5f 0x286faa3 0x220103b 0x2200e9e 0x21ae9c9 0x2209dfa 0x22375cf 0x2237a03 0x59de1 0x11c2753 0x11c2a7b 0x11d0590 0x11d85bd 0x11d8eab 0x11d94a3 0x11d9098 0x1534da3 0x1526ad9 0x1526b54 0x24b7705 0x10e2920 0x10e28b8 0x11a3671 0x11a3bcf 0x11a2d38 0x111233f 0x1112552 0x10f03aa 0x10e1cf8 0x34b3df9 0x34b3ad0 0x313cbf5 0x313c962 0x316dbb6 0x316cf44 0x316ce1b 0x34b27e3 0x34b2668 0x10df65c 0x291d 0x2845）的libC++ abi.dylib ： 终止叫做抛出异常

对取出属性定义的谓词是：

（$ FETCH_SOURCE.tour_id == tour_id）AND（！$ FETCH_SOURCE = SELF）

我已经定义了该数组以返回所有在我的Tour类中接收的所有值。

您是否意识到iOS 6的获取属性有问题？因为我无法理解这在iOS 5中没有问题，但在iOS6中失败。

请参见下面的所有其他相关的代码：

下面的代码是怎么了检索所有记录：

- (void)loadRecordsFromCoreData { 
    [self.managedObjectContext performBlockAndWait:^{ 
     [self.managedObjectContext reset]; 
     NSError *error = nil; 
     NSFetchRequest *request = [[NSFetchRequest alloc] init]; 
     NSEntityDescription *entityDescription = [NSEntityDescription entityForName:NSStringFromClass([Tour class]) inManagedObjectContext:self.managedObjectContext]; 
     [request setEntity:entityDescription]; 
     [request setResultType:NSManagedObjectResultType]; 
     [request setSortDescriptors:[NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"tour_id" ascending:YES]]]; 
     self.tours = [self.managedObjectContext executeFetchRequest:request error:&error]; 
    }]; 

下面的代码鞋NSManagedObjects我已经定义：

- Tour

#import <Foundation/Foundation.h> 
#import <CoreData/CoreData.h> 

@class TourDetail; 

@interface Tour : NSManagedObject 

@property (nonatomic, retain) NSNumber * tour_id; 
@property (nonatomic, retain) NSString * background_url; 
@property (nonatomic, retain) NSString * summary; 
@property (nonatomic, retain) NSString * title; 
@property (nonatomic, retain) NSSet *tourdetails_tour; 

@property (nonatomic, retain) NSArray *tourDetails; 
@end 

@interface Tour (CoreDataGeneratedAccessors) 

- (void)addTourdetails_tourObject:(TourDetail *)value; 
- (void)removeTourdetails_tourObject:(TourDetail *)value; 
- (void)addTourdetails_tour:(NSSet *)values; 
- (void)removeTourdetails_tour:(NSSet *)values; 

@end 
} 
#import "Tour.h" 
#import "TourDetail.h" 


@implementation Tour 

@dynamic tour_id; 
@dynamic background_url; 
@dynamic summary; 
@dynamic title; 
@dynamic tourdetails_tour; 
@dynamic tourDetails; 

@end 

- Tour Detail

#import <Foundation/Foundation.h> 
#import <CoreData/CoreData.h> 

@class Tour; 

@interface TourDetail : NSManagedObject 

@property (nonatomic, retain) NSNumber * id; 
@property (nonatomic, retain) NSNumber * tour_id; 
@property (nonatomic, retain) NSNumber * lattitude; 
@property (nonatomic, retain) NSNumber * longitude; 
@property (nonatomic, retain) NSString * audiofile; 
@property (nonatomic, retain) NSString * detail; 
@property (nonatomic, retain) NSString * title; 
@property (nonatomic, retain) Tour *tour_tourdetails; 

@end 

#import "TourDetail.h" 
#import "Tour.h" 


@implementation TourDetail 

@dynamic id; 
@dynamic tour_id; 
@dynamic lattitude; 
@dynamic longitude; 
@dynamic audiofile; 
@dynamic detail; 
@dynamic title; 
@dynamic tour_tourdetails; 

@end 

任何建议您可以提供将不胜感激:)，以及你可能必须为如何最好地定义获取属性的例子？

感谢， 迈克尔

Answer 1

您使用这里的代码是不干净

- (void)loadRecordsFromCoreData { 
    [self.managedObjectContext performBlockAndWait:^{ 
     [self.managedObjectContext reset]; 
     NSError *error = nil; 
     NSFetchRequest *request = [[NSFetchRequest alloc] init]; 
     NSEntityDescription *entityDescription = [NSEntityDescription entityForName:NSStringFromClass([Tour class]) inManagedObjectContext:self.managedObjectContext]; 
     [request setEntity:entityDescription]; 
     [request setResultType:NSManagedObjectResultType]; 
     [request setSortDescriptors:[NSArray arrayWithObject:[NSSortDescriptor sortDescriptorWithKey:@"tour_id" ascending:YES]]]; 
     self.tours = [self.managedObjectContext executeFetchRequest:request error:&error]; 
    }]; 

事实上，这是一个有点混乱。

你的调用方法，调用一个管理对象的上下文，其还一个同步块，它重置本身没有理由，其中设置一个属性“self.tours”块的外侧内的呼叫本身。都很奇怪。你能解释你为什么这样做吗？

试试这个。

+(void)loadRecordsWithCompletion:(void(^)(NSArray *records, NSError *error))completion { 
    NSManagedObjectContext *context; //Your context 
    NSError *error; 
    NSSortDescriptor *sortDesc = [NSSortDescriptor sortDescriptorWithKey:@"attribute" ascending:YES]; 
    NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"EntityName"]; 
    [request setSortDescriptors:@[sortDesc]]; 
    NSArray *records = [context executeFetchRequest:request 
               error:&error]; 
    completion(records, error); 
}