Question

我有一个对象 OrganizationalUnit ，它通过 parentId 属性链接到父实体。 OrganizationalUnit 还有一个主键属性 ouId （从JSON“_id”字段映射）。

这是我的代码：

RKManagedObjectMapping *ouMapping = [RKManagedObjectMapping mappingForClass:[OrganizationalUnit class] inManagedObjectStore:manager.objectStore];
[ouMapping mapAttributes:@"name",@"type", nil];
[ouMapping mapKeyPath:@"_id" toAttribute:@"ouId"];
[ouMapping setPrimaryKeyAttribute:@"ouId"];

[ouMapping mapKeyPath:@"parent" toAttribute:@"parentId"];

[ouMapping hasOne:@"parent" withMapping:ouMapping];
[ouMapping connectRelationship:@"parent" withObjectForPrimaryKeyAttribute:@"parentId"];

其工作方式与RestKit中的示例相同：

RKManagedObjectMapping* taskMapping = [RKManagedObjectMapping mappingForClass:[Task class] inManagedObjectStore:objectStore];
taskMapping.primaryKeyAttribute = @"taskID";
[taskMapping mapKeyPath:@"id" toAttribute:@"taskID"];
[taskMapping mapKeyPath:@"name" toAttribute:@"name"];
[taskMapping mapKeyPath:@"assigned_user_id" toAttribute:@"assignedUserID"];
[objectManager.mappingProvider setMapping:taskMapping forKeyPath:@"task"];

// Hydrate the assignedUser association via primary key
[taskMapping hasOne:@"assignedUser" withMapping:userMapping];
[taskMapping connectRelationship:@"assignedUser" withObjectForPrimaryKeyAttribute:@"assignedUserID"];

应根据id在本地创建对象之间的关系。

不幸的是，在运行时，当发生接收数据的实际映射时，我收到错误：

*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<__NSCFString 0x6d9c6f0> valueForUndefinedKey:]: this class is not key value coding-compliant for the key _id.'

有什么想法吗？

Answer 1

我认为我已经找到问题的根源，可能是由于孩子们因为他们尚不存在而无法引用父母而引起的。

RestKit映射对象引用id

1 个答案: