将自定义对象保存到 NSUserDefaults

Question

我有一条新闻 ViewController 和一条 TeamViewController。 TeamViewController 包含一个 teamObjects 的 tableView，当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：

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

如果有比将其存储在 NSUserDefaults

中更好的方法，我愿意接受其他建议

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

    }

}

Answer 1

你可以尝试 NSKeyedUnarchiver，如下所示

这里我在 UserDefault 中存储了 UIColor 对象你可以用你的对象改变它

 NSData *colorData = [NSKeyedArchiver archivedDataWithRootObject:color];
[[NSUserDefaults standardUserDefaults] setObject:colorData forKey:@"myColor"];

并检索那个

NSData *colorData = [[NSUserDefaults standardUserDefaults] objectForKey:@"myColor"];
UIColor *color = [NSKeyedUnarchiver unarchiveObjectWithData:colorData];

注意：这是Objective C但我希望你能在Swift

中隐藏它

希望这能解决您的问题

更新：Swift 5

存档在 Swift

do{
    let colorAsData = try NSKeyedArchiver.archivedData(withRootObject: UIColor.red, requiringSecureCoding: true)
    UserDefaults.standard.set(colorAsData, forKey: "myColor")
    UserDefaults.standard.synchronize()
}catch (let error){ 
    #if DEBUG
        print("Failed to convert UIColor to Data : \(error.localizedDescription)")
    #endif
}

在 Swift

取消归档

do{
    if let colorAsData = UserDefaults.standard.object(forKey: "myColor") as? Data{
        if let color = try NSKeyedUnarchiver.unarchivedObject(ofClasses: [UIColor.self], from: colorAsData){
            // Use Color
        }
    }
}catch (let error){
    #if DEBUG
        print("Failed to convert UIColor to Data : \(error.localizedDescription)")
    #endif
}

Answer 2

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并再次取消存档。你可以这样存档

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()

然后像这样取消存档

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

但是如果你这样做你会得到

.Team encodeWithCoder:]: unrecognized selector sent to instance

你必须像这样让团队符合 NSCoding

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")
    }
}

将自定义对象保存到 NSUserDefaults

Save custom objects into NSUserDefaults

nsuserdefaults

ios

swift