非兼容對象的NSCoding（MKMapItem）

Question

嘗試將MKMapItem保存爲我的自定義類的一部分。

import UIKit 
import MapKit 

class Place: NSObject, NSCoding { 

var mapItem : MKMapItem! 
var type : Category! 

init(mapItem: MKMapItem, type: Category) { 
    self.mapItem = mapItem 
    self.type = type 

} 

// MARK: NSCoding 
    required init?(coder decoder: NSCoder) { 

     mapItem = decoder.decodeObject(forKey: "mapItem") as! MKMapItem? 
     type = decoder.decodeObject(forKey: "type") as! Category? 
    } 

    func encode(with coder: NSCoder) { 

     coder.encode(mapItem, forKey: "mapItem") 
     coder.encode(type, forKey: "type") 
    } 

} 

但是這不起作用，因爲MKMapItem不符合NSCoding（編譯器不抱怨，雖然）。我確實懂得如何對自定義類進行編碼，但無法弄清楚如何爲已經由iOS定義的對象執行此操作。

我知道在Objective-C上有一個答案，但真的很喜歡Swift解決方案。謝謝。

PS我試圖繼承MKMapItem並提供「新」初始值設定項，即使這需要在其他地方進行大量的代碼更改。但是，這導致「不能分配給財產：'地標'是一個只能得到的財產」。 「地標」和「isCurrentLocation」都是隻讀的。

import UIKit 
import MapKit 

class NewMapItem: MKMapItem { 


    required init(placemark: MKPlacemark, isCurrentLocation:Bool, name: String,   phoneNumber: String, url: URL, timeZone: TimeZone) { 
    self.placemark = placemark //compiler complains "get-only" 
    self.isCurrentLocation = isCurrentLocation //compiler complains "get-only" 
    self.name = name 
    self.phoneNumber = phoneNumber 
    self.url = url 
    self.timeZone = timeZone 

} 

// MARK: NSCoding 

init?(coder decoder: NSCoder) { 

    placemark = (decoder.decodeObject(forKey: "placemark") as! MKPlacemark?)! //compiler complains "get-only" 
    isCurrentLocation = decoder.decodeBool(forKey: "isCurrentLocation") //compiler complains "get-only" 
    name = decoder.decodeObject(forKey: "name") as? String 
    phoneNumber = decoder.decodeObject(forKey: "phoneNumber") as? String 
    url = decoder.decodeObject(forKey: "url") as! URL? 
    timeZone = decoder.decodeObject(forKey: "timeZone") as! TimeZone? 
} 

func encode(with coder: NSCoder) { 

    coder.encode(placemark, forKey: "placemark") 
    coder.encode(isCurrentLocation, forKey: "isCurrentLocation") 
    coder.encode(name, forKey: "name") 
    coder.encode(phoneNumber, forKey: "phoneNumber") 
    coder.encode(url, forKey: "url") 
    coder.encode(timeZone, forKey: "timeZone") 
} 
} 

Answer 1

我已經想通了。

打破「FUNC編碼（含編碼器：NSCoder）」的mapItem中和「？的init（編碼解碼器：NSCoder）」回來了構建它

我沒拿MKMapItem初始化與標的優勢。

這是我的工作類：

import UIKit 
import MapKit 

class Place: NSObject, NSCoding { 

    var mapItem : MKMapItem! 
    var type : Category! 

    init(mapItem: MKMapItem, type: Category) { 
    self.mapItem = mapItem 
    self.type = type 
    } 

// MARK: NSCoding 
    required init?(coder decoder: NSCoder) { 

    //liberate the properties of mapItem and rebuild it 
    // let isCurrentLocation = decoder.decodeObject(forKey: "isCurrentLocation") as! Bool //don't need set already 
     let name = decoder.decodeObject(forKey: "name") as! String? 
     let phoneNumber = decoder.decodeObject(forKey: "phoneNumber") as! String? 
     let url = decoder.decodeObject(forKey: "url") as! URL? 
     let timeZone = decoder.decodeObject(forKey: "timeZone") as! TimeZone? 
     let placemark = decoder.decodeObject(forKey: "placemark") as! MKPlacemark? 

    self.mapItem = MKMapItem(placemark: placemark!) 
    self.mapItem.name = name 
    self.mapItem.url = url 
    self.mapItem.phoneNumber = phoneNumber 
    //self.mapItem.isCurrentLocation = isCurrentLocation //don't need this. Set already 
    self.mapItem.timeZone = timeZone 

    type = decoder.decodeObject(forKey: "type") as! Category? 

    } 

    func encode(with coder: NSCoder) { 
    let placemark = mapItem.placemark 
    let name = mapItem.name 
    let phoneNumber = mapItem.phoneNumber 
    let url = mapItem.url 
    let timeZone = mapItem.timeZone 

    coder.encode(name, forKey: "name") 
    coder.encode(phoneNumber,forKey: "phoneNumber") 
    coder.encode(url, forKey: "url") 
    coder.encode(timeZone, forKey: "timeZone") 
    coder.encode(type, forKey: "type") 
    coder.encode(placemark, forKey: "placemark") 

    } 

}