Question

我正在做一个需要将用户数据存储在本地的应用程序。我阅读了Apple网站上的文档，它介绍了如何编码基本类型的部分信息，例如String和Int。但是，当我尝试使用[CLLocation]类型进行编码时，它失败了。我在问一些专家是否可以给我一些关于如何在Swift中编码这种类型的提示？

这是关于Model类的代码。

import Foundation
import UIKit
import CoreLocation
import os.log
import CoreData

//route model
//store the model in the local database.
//change all the [CLLocations] to become the String inorder to store it in local.???? not willing
class Route:  NSObject, NSCoding {
    //MARK: Properties
     var name :String
     var area : String
     var image: UIImage?
     var date : DispatchTime
     var routePoints = [CLLocation]()
     var rating: Int

     //MARK: Achieving paths
    //static properties, belong to the
    static let DocumentsDirectory = FileManager().urls(for: .documentDirectory, in: .userDomainMask).first!
    static let ArchiveURL = DocumentsDirectory.appendingPathComponent("Routes")

    //MARK: NSCoding
    func encode(with aCoder: NSCoder) {
        aCoder.encode(name, forKey: PropertyKey.name)
        aCoder.encode(image, forKey: PropertyKey.image)
        aCoder.encode(date, forKey: PropertyKey.date)
        aCoder.encode(area, forKey: PropertyKey.area)
        //unable to encode the [cllocation]
        aCoder.encode(routePoints, forKey: PropertyKey.routePoints)
        aCoder.encode(rating, forKey: PropertyKey.rating)
    }
    //should also added in the locations as one of the variable.
    init?(Name: String, Area: String, Date: DispatchTime, Image: UIImage?, RoutePoints: [CLLocation], Rating: Int) {
        guard (Rating >= 0) && (Rating <= 5) else {
            return nil
        }
        self.name = Name
        self.area = Area
        self.image = Image
        self.date = Date
        self.routePoints = RoutePoints
        self.rating = Rating
    }



    required convenience init?(coder aDecoder: NSCoder){
        //this is the necessary property
        //these are optional properties
        let rating = aDecoder.decodeInteger(forKey: PropertyKey.rating)
       guard   let date = aDecoder.decodeObject(forKey: PropertyKey.date) as? DispatchTime,
        let name = aDecoder.decodeObject(forKey: PropertyKey.name) as? String,
        let image = aDecoder.decodeObject(forKey: PropertyKey.image) as? UIImage,
        let area = aDecoder.decodeObject(forKey: PropertyKey.area) as? String,
        let routePoints = aDecoder.decodeObject(forKey: PropertyKey.routePoints) as? [CLLocation] else{
            print("Unable to decode")
            return nil
        }
        self.init(Name: name, Area: area, Date: date, Image: image, RoutePoints: routePoints, Rating: rating)

    }



    //MARK: Types
    struct PropertyKey {
        static let name = "name"
        static let image = "image"
        static let date = "date"
        static let area = "area"
        static let rating = "rating"
        static let routePoints = "routePoints"
    }


}

祝福

Answer 1

原因是CLLocation不能与NSCoder一起存储。您可以使用swift map为这种类型的值实现一个简单的编码器/解码器，以基本上将位置存储在字典中。

else if(strLine.equals("quit")){
        while(!stack.isEmpty()){
        pw.println(getObject(stack.pop()));
    } 
} // quit


private Object getObject(Object obj) {
        String objStr = null;
        if(obj instanceof String){
          String objStr = (String)obj;
          }
    Object resp = (objStr == null)? obj: objStr.replaceAll("\"","");
    return resp;
}

如何在swift中正确编码[CLLocation]？

1 个答案: