将自定义对象保存到 NSUserDefaults [英] Save custom objects into NSUserDefaults

问题描述

我有一个新闻 ViewController 和一个 TeamViewController.TeamViewController 包含一个 teamObjects 的 tableView，当它被选中时被添加到数组中.我想将此数组添加到 NSUserDefaults 中，以便我可以从 NewsController 访问它们，其中包含需要 teamObjects 的 url 请求.但是我不断得到:

I'm having a news ViewController and a TeamViewController. The TeamViewController contain a tableView of teamObjects which when selected is added into array. I want to add this array into NSUserDefaults so i can access them from the NewsController which contain a url request where the teamObjects is needed. However i keep getting:

'尝试插入非属性列表对象(") 用于关键团队

'Attempt to insert non-property list object ( "" ) for key teams'

如果有比将其存储在 NSUserDefaults

didSelectRowAtIndexPath 方法

override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
    tableView.deselectRowAtIndexPath(indexPath, animated: true)


    let team = self.teamArray[indexPath.row] as Team
    var removed = false

    for (index, value) in enumerate(self.teamSelected) {
        if (value == team) {
            self.teamSelected.removeAtIndex(index)
            removed = true
        }
    }

    if (!removed) {
        self.teamSelected.append(team)
    }

    var userDefaults = NSUserDefaults.standardUserDefaults()
    userDefaults.setValue(self.teamSelected, forKey: "teams")
    userDefaults.synchronize()

    tableView.reloadData()
}

我的对象

class Team: NSObject{
    var id: Int!
    var name: NSString!
    var shortname: NSString!


    init(id: Int, name:NSString, shortname: NSString) {
        self.id = id
        self.name = name
        self.shortname = shortname

    }

}

推荐答案

实际上，您需要将自定义对象存档到 NSData 然后将其保存到用户默认值并从用户默认值中检索它并取消存档再说一遍.你可以这样存档

Actually, you will need to archive the custom object into NSData then save it to user defaults and retrieve it from user defaults and unarchive it again. You can archive it like this

let teams = [Team(id: 1, name: "team1", shortname: "t1"), Team(id: 2, name: "team2", shortname: "t2")]

var userDefaults = UserDefaults.standard
let encodedData: Data = NSKeyedArchiver.archivedData(withRootObject: teams)
userDefaults.set(encodedData, forKey: "teams")
userDefaults.synchronize()

然后像这样解压

let decoded  = userDefaults.data(forKey: "teams")
let decodedTeams = NSKeyedUnarchiver.unarchiveObject(with: decoded) as! [Team]

但是如果你这样做了，你就会得到

But if you just did that you will get

.Team encodeWithCoder:]: unrecognized selector sent to instance

你必须像这样让 Team 符合 NSCoding

You will have to make Team conform to NSCoding just like this

class Team: NSObject, NSCoding {
    var id: Int
    var name: String
    var shortname: String


    init(id: Int, name: String, shortname: String) {
        self.id = id
        self.name = name
        self.shortname = shortname

    }

    required convenience init(coder aDecoder: NSCoder) {
        let id = aDecoder.decodeInteger(forKey: "id")
        let name = aDecoder.decodeObject(forKey: "name") as! String
        let shortname = aDecoder.decodeObject(forKey: "shortname") as! String
        self.init(id: id, name: name, shortname: shortname)
    }

    func encode(with aCoder: NSCoder) {
        aCoder.encode(id, forKey: "id")
        aCoder.encode(name, forKey: "name")
        aCoder.encode(shortname, forKey: "shortname")
    }
}

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