[英]Nested array of double in realm (swift)
我有這個 JSON:
{
"location": {
"position": {
"type": "Point",
"coordinates": [
45.579553,
11.751805
]
}
}
}
屬於另一個 JSON 對象。
試圖用 Realm 和 ObjectMapper 映射它,我發現映射coordinates
屬性是一個雙精度數組的困難。
這就是閱讀文檔和 SO 似乎有意義的內容:
import Foundation
import RealmSwift
import ObjectMapper
class Coordinate:Object, Mappable{
dynamic var latitude:Double = 0.0
dynamic var longitude:Double = 0.0
required convenience init?(_ map: Map) {
self.init()
}
func mapping(map: Map) {
latitude <- map[""]
longitude <- map[""]
}
}
class Position: Object, Mappable{
var type:String = ""
var coordinates:Coordinate?
required convenience init?(_ map: Map) {
self.init()
}
func mapping(map: Map) {
type <- map["type"]
coordinates <- map["coordinates"]
}
}
class Location: Object, Mappable{
dynamic var id = ""
dynamic var position:Position?
dynamic var desc = ""
override static func indexedProperties()->[String]{
return["id"]
}
override class func primaryKey() -> String? {
return "id"
}
required convenience init?(_ map: Map) {
self.init()
}
func mapping(map: Map) {
id <- map["id"]
position <- map["position"]
}
}
但是我一直在理解如何映射“坐標”對象。 請注意,此問題與 ObjectMapper 本身無關,更多的是關於如何將 Double 數組分配給 Realm 模型中的屬性的問題。
我能夠按照此問題中的指示解決此問題:
https://github.com/realm/realm-cocoa/issues/1120 (學分@jazz-mobility)
class DoubleObject:Object{
dynamic var value:Double = 0.0
}
class Position: Object, Mappable{
var type:String = ""
var coordinates = List<DoubleObject>()
required convenience init?(_ map: Map) {
self.init()
}
func mapping(map: Map) {
type <- map["type"]
var coordinates:[Double]? = nil
coordinates <- map["coordinates"]
coordinates?.forEach { coordinate in
let c = DoubleObject()
c.value = coordinate
self.coordinates.append(c)
}
}
}
您現在可以簡單地使用List<Double>()
而無需存儲對象。
更多信息可以在這里找到: https : //academy.realm.io/posts/realm-list-new-superpowers-array-primitives/
@objcMembers class RealmObject: Object, Mappable {
dynamic var listValues = List<MyRealmObject>()
required convenience init?(map: Map) {
self.init()
}
// Mappable
func mapping(map: Map) {
listValues <- (map["listValues"], RealmlistObjectTransform())
}
}
@objcMembers class MyRealmObject: Object, Mappable {
required convenience init?(map: Map) {
self.init()
}
// Mappable
func mapping(map: Map) {
}
}
class RealmlistObjectTransform: TransformType {
typealias Object = List<MyRealmObject> // My Realm Object here
typealias JSON = [[String: Any]] // Dictionary here
func transformFromJSON(_ value: Any?) -> List<MyRealmObject>? {
let list = List<MyRealmObject>()
if let actors = value as? [[String: Any]] {
let objects = Array<MyRealmObject>(JSONArray: actors)
list.append(objectsIn: objects)
}
return list
}
func transformToJSON(_ value: List<MyRealmObject>?) -> [[String: Any]]? {
if let actors = value?.sorted(byKeyPath: "").toArray(ofType: MyRealmObject.self).toJSON() {
return actors
}
return nil
}
}
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.