RestKit 0.23.1一對多關係映射不起作用

Question

我一直在努力研究如何使用RestKit 0.23.1過去幾天將此JSON數據映射到Core Data中的管理對象。我的數據包含多個「對象」，每個都有自己的一個或多個「鏈接」，這是包含預覽信息的URL結構化對象列表：

objects": [ 

{ 
    "id": "03fbbec709d261c87a64d979fe1e530b", 
    "object_type": "note", 
    "links": [ 
    { 
     "id": "d48066cf6daa007e31f8915831f46fc2", 
     "urlSite": "techcrunch.com", 
     "siteName": null, 
     "urlString": "http://techcrunch.com/2014/06/16/secret-finally-lets-all-your-freaky-friends-have-their-own-feed/", 
     "urlShortened": "http://gcq.me/1vzsVJY", 
     "title": "Secret Finally Lets All Your Freaky Friends Have Their Own Feeds | TechCrunch", 
     "previewImage": "http://tctechcrunch2011.files.wordpress.com/2014/06/secret2.jpg?w=650", 
     "previewText": "Secret Finally Lets All Your Freaky Friends Have Their Own Feeds | TechCrunch", 
     "lastUpdated": "2014-06-17 06:50:56", 
     "lastVisited": "2014-06-17 06:50:56", 
     "visitCount": 0 
    } 

    ] 
}] 

我創建功能，以幫助建立我的地圖關係：

+ (RKEntityMapping*)webLinkMapping { 
RKManagedObjectStore* managedObjectStore = [RKManagedObjectStore defaultStore]; 
RKEntityMapping *mapping = [RKEntityMapping mappingForEntityForName:@"WebLink" inManagedObjectStore:managedObjectStore]; 

mapping.identificationAttributes = @[ @"objectId" ]; 
[mapping addAttributeMappingsFromDictionary:@{@"id": @"objectId"}]; 

[mapping addAttributeMappingsFromArray:@[ @"urlSite", @"siteName", @"urlString", @"urlShortened", 
              @"title", @"previewImage", @"previewText", @"lastUpdated", 
              @"lastVisited", @"visitCount"]]; 

return mapping; 
} 

+ (RKEntityMapping*)streamObjectMapping { 
RKManagedObjectStore* managedObjectStore = [RKManagedObjectStore defaultStore]; 
RKEntityMapping *mapping = [RKEntityMapping mappingForEntityForName:@"StreamObject" inManagedObjectStore:managedObjectStore]; 
mapping.identificationAttributes = @[ @"objectId" ]; 

[mapping addAttributeMappingsFromDictionary:@{ 
    @"id":      @"objectId", 
}]; 
[mapping addAttributeMappingsFromArray:@[ @"object_type"]]; 

[mapping addRelationshipMappingWithSourceKeyPath:@"links" mapping:[self webLinkMapping]]; 
//[mapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:@"links" toKeyPath:@"links" withMapping:[self webLinkMapping]]]; 

return mapping; 
} 

我幾乎可以肯定它是對的鏈接陣列周圍方括號中是導致我的映射沒有工作權的JSON返回。我不斷收到關係的故障在我返回的流對象：

links = "<relationship fault: 0x114a05820 'links'>"; 

使用源碼的瀏覽器，我看到我的鏈接對象存儲與父對象的正確關聯OBJECTID在實際的數據表看，所以當我詢問我的流對象時，它們只是沒有被正確地返回。有關我如何糾正此問題的任何想法？

關於加載到內存中，它似乎沒有被這樣做：

RKStreamObject* postObject = [_postObjects objectAtIndex:indexPath.row]; 

NSLog(@"Links: %@", postObject.links); 


2014-06-20 11:25:11.249 MyApp[6026:151920] Links: Relationship 'links' fault on managed object (0x110c47ee0) <RKStreamObject: 0x110c47ee0> (entity: StreamObject; id: 0xd000000001000000 <x-coredata://F96BC470-82A5-4C56-81A9-71C6129F967B/StreamObject/p64> ; data: { 
body = "http://techcrunch.com/2014/06/16/secret-finally-lets-all-your-freaky-friends-have-their-own-feed/"; 
"comment_count" = 0; 
controllerSource = nil; 
"gc_updated" = "2014-06-20 16:25:10 +0000"; 
"liked_by_me" = 0; 
likes = 0; 
links = "<relationship fault: 0x1141bce40 'links'>"; 
objectId = 03fbbec709d261c87a64d979fe1e530b; 
"object_type" = note; 
photo = nil; 
"photo_feed" = nil; 
"photo_height" = 0; 
"photo_width" = 0; 
place = "0xd000000000100002 <x-coredata://F96BC470-82A5-4C56-81A9-71C6129F967B/Place/p4>"; 
privacy = F; 
"subscribed_by_me" = 1; 
timestamp = "2014-06-17T06:51:00-05:00"; 
"timestamp_as_words" = "3 days ago"; 
"timestamp_formatted" = "Tuesday, June 17, 2014 at 06:51:00 CDT"; 
"timestamp_unix" = 1403005860; 
user = "0xd0000000000c0004 <x-coredata://F96BC470-82A5-4C56-81A9-71C6129F967B/User/p3>"; 
videoId = nil; 
videoSource = nil; 
}) 

的通知「的地方」和「用戶」是如何出現好嗎？這些是1對1的對象映射，可以很好地工作。當我直接在NSLog語句中調用它們時，不應該出現鏈接？

根據Wain的建議進行最終編輯時，我從關係數組中拉出第一個對象，並返回相關的Web鏈接。

if ([postObject.links count] > 0) { 
    RKWebLink *link = [[postObject.links allObjects] objectAtIndex:0]; 
    NSLog(@"Link title: %@", link.title); 
} 

Answer 1

links = "<relationship fault: 0x114a05820 'links'>"; 

這並不意味着關係的內容並不存在，它只是意味着它沒有被加載到內存中，但（這是一個錯誤）。當您嘗試使用關係內容時，它將被加載。

你的代碼看起來不錯。方括號意味着你有一個數組/對象列表而不是一個，並且不是問題（這是一件好事）。