ios - 从根节点映射嵌套对象不起作用

Question

使用 ObjectMapper( https://github.com/Hearst-DD/ObjectMapper )，我正在将 JSON 转换为 Swift 对象。应用程序在访问 user.profession 时崩溃。

基本上，我不知道如何解析模型中具有相同 JSON 映射根节点的另一个可映射对象，我想，我做错了。我在任何地方都找不到相同的文档。

JSON 字典:

user: {
  "name": "Dinesh",
  "url": "https://dinaraja.me",
  "company": "IIINC",
  "designation": "Developer"
}

型号:

struct User: Mappable {
  var name: String!
  var url: URL!
  var profession: Profession!
  init(_ map: Map) {
    name <- map["name"]
    url <- map["url"]
    profession <- map   // FIXME: It's not working. Find out what we do here is right/wrong
  }
}
struct Profession: Mappable {
  var company: String!
  var designation: String!
  init(_ map: Map) {
    company <- map["company"]
    designation <- map["designation"]
  }
}

我做了什么:

let user = Mapper<User>().map(myJSONDictionary)
print(user.profession.company) //FIXME: Crashes here

如有任何帮助，我们将不胜感激。

Answer 1

自 profession其模型未直接包含在 user 中json 模型你不应该使用对象映射器 <-运营商在这种情况下。相反，您应该初始化新的 Profession直接来自 user 的对象映射函数

struct User: Mappable {
    var name: String!
    var url: URL!
    var profession: Profession!

    init(map: Map) {

    }

    mutating func mapping(map: Map) {

        name <- map["name"]
        url <- map["url"]
        profession = Profession(map: map)
    }
}

struct Profession: Mappable {
    var company: String!
    var designation: String!

    init(map: Map) {
        company <- map["company"]
        designation <- map["designation"]
    }

    mutating func mapping(map: Map) {
        company <- map["company"]
        designation <- map["designation"]
    }
}