Question

我检查了与我的问题类似的问题（例如this和this），但我无法找到问题的解决方案。我尝试使用Restkit's object mapping page中的教程来映射我的数据，但我无法得到我需要的结果。如果有人可以指出我的错误，我会非常感激。

我的问题

当我尝试获取数据时，我的应用程序崩溃，并且我得到“此类不是键码'GameId'的关键值编码。”。我相信我正在映射项目并回答数组错误。

我想要映射的JSON

样品：

{
  "GameId": 1,
  "Items": [
    {
      "Id": 1,
      "PicUrl": "sample string 2",
      "Answers": [
        "sample string 1",
        "sample string 2",
        "sample string 3"
      ],
      "CorrectAnswer": "sample string 3",
      "Difficulty": 4,
      "CategoryId": 5,
      "CategoryName": "sample string 6",
      "AccountId": 7
    },
    {
      "Id": 1,
      "PicUrl": "sample string 2",
      "Answers": [
        "sample string 1",
        "sample string 2",
        "sample string 3"
      ],
      "CorrectAnswer": "sample string 3",
      "Difficulty": 4,
      "CategoryId": 5,
      "CategoryName": "sample string 6",
      "AccountId": 7
    },
    {
      "Id": 1,
      "PicUrl": "sample string 2",
      "Answers": [
        "sample string 1",
        "sample string 2",
        "sample string 3"
      ],
      "CorrectAnswer": "sample string 3",
      "Difficulty": 4,
      "CategoryId": 5,
      "CategoryName": "sample string 6",
      "AccountId": 7
    }
  ],
  "StartTime": "2013-10-07T00:24:22.0048045+00:00"
}

我的数据类

CurrentGames.h

#import <Foundation/Foundation.h>

@interface CurrentGames : NSObject

@property (nonatomic,retain) NSNumber *GameId;
@property(nonatomic,strong)NSArray *items;
@property(nonatomic,retain) NSNumber *ID;
@property(nonatomic,retain) NSURL *pictureUrl;
@property (nonatomic,strong) NSArray *answers;
@property(nonatomic,retain) NSString *ans1;
@property (nonatomic,retain)NSString *ans2;
@property(nonatomic,retain)NSString *ans3;
@property (nonatomic,retain)NSString *ans4;
@property(nonatomic,retain) NSString *correctAnswer;
@property(nonatomic,retain) NSString *difficulty;
@property(nonatomic,retain) NSString *categoryID;
@property(nonatomic,retain)NSString *categoryName;
@property(nonatomic,retain)NSString *accountID;

@end

CurrentGames.m

#import "CurrentGames.h"

@implementation CurrentGames

- (id)init
{
    self = [super init];
    if (self)
    {
        _answers = [[NSArray alloc]initWithObjects:_ans1,_ans2,_ans3,_ans4, nil];
        _items =[[NSArray alloc]initWithObjects:_ID,_pictureUrl,_answers,_correctAnswer,_categoryID,_categoryName,_accountID, nil];

    }
    return self;
}

@end

我尝试映射的方式

-(void)loadGame
{
    RKObjectMapping* currentGameMapping = [RKObjectMapping mappingForClass:[CurrentGames class]];
    [currentGameMapping addAttributeMappingsFromDictionary:@{
                                                             @"GameId":@"GameId",
                                                             @"Items": @"items",
                                                             @"Id":@"ID",
                                                             @"PicUrl":@"pictureUrl",
                                                             @"Answers":@"answers",
                                                             @"CorrectAnswer": @"correctAnswer",
                                                             @"Difficulty":@"difficulty",
                                                             @"CategoryId":@"categoryID",
                                                             @"CategoryName":@"categoryName",
                                                             @"AccountId":@"accountID",


                                                             }];
    RKResponseDescriptor *responseDescriptor =[RKResponseDescriptor responseDescriptorWithMapping:currentGameMapping method:RKRequestMethodGET pathPattern:nil keyPath:@"GameId" statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];

    NSURL *URL = [NSURL URLWithString:@"https://picquiz.azurewebsites.net/Games/Current/13"];

    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];
    }

控制台

2013-10-07 20:16:38.824 FlickRest[1253:a0b] I restkit:RKLog.m:34 RestKit logging initialized...
2013-10-07 20:16:38.952 FlickRest[1253:a0b] I restkit.network:RKObjectRequestOperation.m:180 GET 'https://picquiz.azurewebsites.net/Games/Current/13'
2013-10-07 20:16:39.622 FlickRest[1253:3407] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<__NSCFNumber 0x8bb3080> 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                           0x0007e891 -[RKMappingSourceObject valueForKeyPath:] + 833
    8   FlickRest                           0x00083ea7 -[RKMappingOperation applyAttributeMappings:] + 1671
    9   FlickRest                           0x0008b89e -[RKMappingOperation main] + 4062
    10  Foundation                          0x00ca9a69 -[__NSOperationInternal _start:] + 671
    11  Foundation                          0x00c26798 -[NSOperation start] + 83
    12  FlickRest                           0x00078f25 -[RKMapperOperation mapRepresentation:toObject:atKeyPath:usingMapping:metadata:] + 1957
    13  FlickRest                           0x000777a0 -[RKMapperOperation mapRepresentation:atKeyPath:usingMapping:] + 1904
    14  FlickRest                           0x0007a11d -[RKMapperOperation mapRepresentationOrRepresentations:atKeyPath:usingMapping:] + 829
    15  FlickRest                           0x0007aa72 -[RKMapperOperation mapSourceRepresentationWithMappingsDictionary:] + 2210
    16  FlickRest                           0x0007b43b -[RKMapperOperation main] + 1403
    17  Foundation                          0x00ca9a69 -[__NSOperationInternal _start:] + 671
    18  Foundation                          0x00c26798 -[NSOperation start] + 83
    19  FlickRest                           0x000cb7da -[RKObjectResponseMapperOperation performMappingWithObject:error:] + 1354
    20  FlickRest                           0x000c9813 -[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
Program ended with exit code: 0

Answer 1

您的问题是您的响应描述符设置为keyPath:@"GameId"，实际上应该是keyPath:nil。您当前的配置会导致所有映射都应用于NSNumber实例（显然不起作用）。

Reskit 0.20.1映射JSON valueForUndefinedKey错误

1 个答案: