使用 RestKit 序列化带有子对象的对象 [POSTing]答案

【问题标题】：using RestKit to serialize an object with a subobject [POSTing]使用 RestKit 序列化带有子对象的对象 [POSTing]
【发布时间】：2012-03-13 21:16:58
【问题描述】：

我有以下对象设置：

RKObjectMapping* geoPointMapping = [RKObjectMapping mappingForClass:[CRGeoPoint class]];

geoPointMapping.setDefaultValueForMissingAttributes = YES;
[geoPointMapping mapKeyPathsToAttributes:
    @"longitude", @"longitude",
    @"latitude", @"latitude",
    nil];
[objectManager.mappingProvider registerMapping:geoPointMapping withRootKeyPath:@"geometry"];

RKObjectMapping* criteriaMapping = [RKObjectMapping mappingForClass:[CRCriteria class]];

criteriaMapping.setDefaultValueForMissingAttributes = YES;
[criteriaMapping mapKeyPathsToAttributes:
    @"type", @"type",
    @"geometry", @"geometry",
    @"fromDate", @"fromDate",
    @"toDate", @"toDate",
    @"radius", @"radius",
    nil];
[objectManager.mappingProvider registerMapping:criteriaMapping withRootKeyPath:@"criteria"];

但是当我尝试发送查询（使用几何对象）时。我一直收到此错误：

收到错误 Error Domain=JKErrorDomain Code=-1 "无法序列化对象类 CRGeoPoint。”

【问题讨论】：

标签： ios restkit

【解决方案1】：

入站和出站映射信息由RKObjectMappingProvider 分别处理。您已经在该代码中配置了入站映射（从您的服务器下载数据）。但是——RestKit 组中的as pointed out by Shane Zatezalo——您还需要为 RestKit 添加一个序列化映射，以了解如何将您的对象转换为 JSON（或您可能使用的任何其他序列化格式）。

查看对象序列化的Object Mapping tutorial's 部分。看看source for the mapping provider，让自己放心，这些东西是分开的。

【讨论】：

感谢指向文档的指针，您和 Shane 都部分正确。但是医生指出了完整答案的方法。我不仅需要创建逆映射，还需要指定用于关系的映射。
是的，我对此困惑了很长时间。最终我意识到我需要向映射提供者注册映射（由资源路径键入），并分别向路由器注册类资源路径。

【解决方案2】：

OP 的解决方案。

解决方案有两个。首先，我必须指定下面 Sixten 指出的逆映射，其次我必须指定用于 CRCriteria 对象上的 CRGeoPoint 类的映射。代码如下：

RKObjectMapping* geoPointMapping = [RKObjectMapping mappingForClass:[CRGeoPoint class]];

geoPointMapping.setDefaultValueForMissingAttributes = YES;

[objectManager.mappingProvider registerMapping:geoPointMapping withRootKeyPath:@"geometry"];

// Build a serialization mapping by inverting our object mapping. Includes attributes and relationships
RKObjectMapping* geoPointSerializationMapping = [geoPointMapping inverseMapping];
// You can customize the mapping here as necessary -- adding/removing mappings
[[RKObjectManager sharedManager].mappingProvider setSerializationMapping:geoPointSerializationMapping forClass:[CRGeoPoint class]]; 

RKObjectMapping* criteriaMapping = [RKObjectMapping mappingForClass:[CRCriteria class]];

criteriaMapping.setDefaultValueForMissingAttributes = YES;
[criteriaMapping mapKeyPathsToAttributes:
 @"type", @"type",
 @"fromDate", @"fromDate",
 @"toDate", @"toDate",
 @"radius", @"radius",
 nil];
[criteriaMapping mapKeyPath:@"geometry" toRelationship:@"geometry" withMapping:geoPointMapping];
[objectManager.mappingProvider registerMapping:criteriaMapping withRootKeyPath:@"criteria"];

// Build a serialization mapping by inverting our object mapping. Includes attributes and relationships
RKObjectMapping* criteriaSerializationMapping = [criteriaMapping inverseMapping];
// You can customize the mapping here as necessary -- adding/removing mappings
[[RKObjectManager sharedManager].mappingProvider setSerializationMapping:criteriaSerializationMapping forClass:[CRCriteria class]];

【讨论】：