ios - Realm 返回具有空 RLMArray 作为属性的对象

Question

我有类Country。它是 RLMObject 的一个简单子(monad)类。基本上，当我保存 Country 时，它们确实有 regions (RLMArray 类型的属性包含几个 Region 类型的对象。它们是 RLMObject 子类)但是当我获取它时来自 Realm 然后 regions 为零。

我用浏览器仔细检查了 Realm ，那些数据就在那里。也许我使用了错误的技术来获取这些数据？

此时我使用 realm-objc 因为我必须支持设备

国家/地区(27 行)

public class Country: RLMObject {
   public dynamic var name = ""
   public dynamic var desc = ""
    public dynamic var id = 0
    public var regions = RLMArray(objectClassName: Region.className())
    override public static func primaryKey() -> String? {
        return "id"
    }

    override init!() {
        super.init()
    }

    public func configure(id:Int,json:JSON){
        self.name = json["name"].stringValue
        if let desc = json["desc"].string {
            self.desc = desc
        }
        for (key:String, value:JSON) in json["regions"] {
            let region = Region()
            region.configure(key.toInt()!,json:value)
            self.regions.addObject(region)

        }
        self.id = json["id"].intValue
    }
}

CountryManager(36 行)

public class CountryManager: NSObject {

    public func saveWines(json:JSON) {
        var countriesForStore = [Country]()
        let db = RLMRealm.defaultRealm()
        for (key:String, subJson:JSON) in json{
            let country = Country() //Serialize each country
            country.configure(key.toInt()!,json:subJson)
            countriesForStore.append(country)
        }

        db.beginWriteTransaction()
        db.addOrUpdateObjectsFromArray(countriesForStore)
        db.commitWriteTransaction()
    }

    public func regionsForCountryWithNameLike(name:String) -> RLMResults {
        let db = RLMRealm.defaultRealm()
        let countryPredicate = NSPredicate(format: "name CONTAINS[c] %@", name)
        let countries = Country.objectsWithPredicate(countryPredicate)

        var rawRegionNames = [String]()
        for country in countries {
            if let c = country as? Country {
                for region in c.regions{
                    rawRegionNames.append((region as! Region).name)
                }
            }

        }
        let regionNames = "','".join(rawRegionNames)
        let regionPredicate = NSPredicate(format: "name IN {'\(regionNames)'}")
        let regions = Region.objectsInRealm(db, withPredicate: regionPredicate)
        return regions
    }
}

Answer 1

尝试将 public var regions 更改为 dynamic public var regions，因为 Realm 要求 RLMArray 属性是动态的。