您好我在使用restkit从api映射数据时遇到问题。我有以下数据。我非常感谢任何可以指出我的错误的人。
{"GameId":1,"Items":
[{"Id":1,"PicUrl":"someurlhere","Answers":
["Paris","New York","San Francisco","Rome"],"CorrectAnswer":"San Francisco","Categories"}]}
这就是我计划在客户端存储数据的方式：
#import <Foundation/Foundation.h>
GameObjects.h
@interface GameObjects : NSObject
@property(nonatomic, strong)NSNumber *GameId;
@property(nonatomic,strong)NSMutableArray *Items;
@property(nonatomic,strong)NSNumber *IId;
@property(nonatomic,strong)NSURL *PicUrl;
@property(nonatomic,strong)NSMutableArray *Answers;
@property(nonatomic,strong)NSString *CorrectAnswer;
@property(nonatomic,strong)NSString *CategoryName;
@end
GameObjects.m
#import "GameObjects.h"
@implementation GameObjects
@synthesize GameId;
@synthesize Items;
@synthesize Answers;
@synthesize IId;
@synthesize CategoryName;
@synthesize CorrectAnswer;
@synthesize PicUrl;
- (id)init
{
self = [super init];
if (self) {
Items = [[NSMutableArray alloc]initWithObjects:PicUrl,Answers,CorrectAnswer,CategoryName, nil];
}
return self;
}
@end
这就是我如何进行映射：
-(void)viewDidLoad
{
//restkit
RKObjectMapping *GameMapping = [RKObjectMapping mappingForClass:[GameObjects class]];
[GameMapping addAttributeMappingsFromDictionary:@{ @"GameId":@"GameId",
@"Items": @"Items",
@"Id": @"Id",
@"PicUrl": @"PicUrl",
@"Answers":@"Answers",
@"CorrectAnswer":@"CorrectAnswer",
@"CategoryName":@"CategoryName"
}];
RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:GameMapping method:RKRequestMethodGET pathPattern:nil keyPath:@"GameId" statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];
NSURL *URL = [NSURL URLWithString:@"someurlhere"];
NSURLRequest *request =[NSURLRequest requestWithURL:URL];
RKObjectRequestOperation *objectRequestOperation = [[RKObjectRequestOperation alloc]initWithRequest:request responseDescriptors:@[responseDescriptor]];
[objectRequestOperation setCompletionBlockWithSuccess:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
RKLogInfo(@"Load collection of Articles: %@", mappingResult.array);
} failure:^(RKObjectRequestOperation *operation, NSError *error) {
RKLogError(@"Operation failed with error: %@", error);
}];
[objectRequestOperation start];
}
我的输出：
2013-09-30 14:28:04.204 FlickRest[3826:a0b] I restkit:RKLog.m:34 RestKit logging initialized...
2013-09-30 14:28:04.478 FlickRest[3826:a0b] ViewController - viewDidLoad
2013-09-30 14:28:12.158 FlickRest[3826:a0b] I restkit.network:RKObjectRequestOperation.m:180 GET 'someurlhere'
2013-09-30 14:28:18.243 FlickRest[3826:1a07] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<__NSCFNumber 0x8e20580> valueForUndefinedKey:]: this class is not key value coding-compliant for the key GameId.'
*** First throw call stack:
(
0 CoreFoundation 0x020ca5e4 __exceptionPreprocess + 180
1 libobjc.A.dylib 0x01e4d8b6 objc_exception_throw + 44
2 CoreFoundation 0x0215a6a1 -[NSException raise] + 17
3 Foundation 0x00c95b0a -[NSObject(NSKeyValueCoding) valueForUndefinedKey:] + 282
4 Foundation 0x00c02b61 _NSGetUsingKeyValueGetter + 81
5 Foundation 0x00c0219b -[NSObject(NSKeyValueCoding) valueForKey:] + 260
6 Foundation 0x00c21c9a -[NSObject(NSKeyValueCoding) valueForKeyPath:] + 409
7 FlickRest 0x0007fc31 -[RKMappingSourceObject valueForKeyPath:] + 833
8 FlickRest 0x00085247 -[RKMappingOperation applyAttributeMappings:] + 1671
9 FlickRest 0x0008cc3e -[RKMappingOperation main] + 4062
10 Foundation 0x00ca9a69 -[__NSOperationInternal _start:] + 671
11 Foundation 0x00c26798 -[NSOperation start] + 83
12 FlickRest 0x0007a2c5 -[RKMapperOperation mapRepresentation:toObject:atKeyPath:usingMapping:metadata:] + 1957
13 FlickRest 0x00078b40 -[RKMapperOperation mapRepresentation:atKeyPath:usingMapping:] + 1904
14 FlickRest 0x0007b4bd -[RKMapperOperation mapRepresentationOrRepresentations:atKeyPath:usingMapping:] + 829
15 FlickRest 0x0007be12 -[RKMapperOperation mapSourceRepresentationWithMappingsDictionary:] + 2210
16 FlickRest 0x0007c7db -[RKMapperOperation main] + 1403
17 Foundation 0x00ca9a69 -[__NSOperationInternal _start:] + 671
18 Foundation 0x00c26798 -[NSOperation start] + 83
19 FlickRest 0x000ccb7a -[RKObjectResponseMapperOperation performMappingWithObject:error:] + 1354
20 FlickRest 0x000cabb3 -[RKResponseMapperOperation main] + 2371
21 Foundation 0x00ca9a69 -[__NSOperationInternal _start:] + 671
22 Foundation 0x00c26798 -[NSOperation start] + 83
23 Foundation 0x00cabd34 __NSOQSchedule_f + 62
24 libdispatch.dylib 0x028de4b0 _dispatch_client_callout + 14
25 libdispatch.dylib 0x028cc088 _dispatch_queue_drain + 450
26 libdispatch.dylib 0x028cbe85 _dispatch_queue_invoke + 126
27 libdispatch.dylib 0x028cce25 _dispatch_root_queue_drain + 83
28 libdispatch.dylib 0x028cd13d _dispatch_worker_thread2 + 39
29 libsystem_c.dylib 0x02bf6e72 _pthread_wqthread + 441
30 libsystem_c.dylib 0x02bdedaa start_wqthread + 30
)
libc++abi.dylib: terminating with uncaught exception of type NSException
答案 0 :(得分：5)
您已设置响应描述符keyPath:@"GameId"，但它应为keyPath:nil。通过将其设置为@"GameId"，RestKit将导航到JSON并尝试将所有映射内容应用于为NSNumber密钥设置的GameId值。
答案 1 :(得分：0)
＆＃39;此类不是密钥值编码兼容的密钥＆＃39;当映射中定义的键值关系与某个级别的JSON键值不匹配时，通常会发生此错误。在您的情况下，将keyPath设置为＆＃39; GameId＆＃39;意味着您的JSON必须具有root键作为＆＃39; GameId＆＃39;情况并非如此，导致崩溃。