Save Custom Dictionary to User default

Question

struct AllItemsData {
    var DSTBID: String!
    var CCAS: String!
    var BCAS: String!
}

This is my structure from which I create an array of type AllItemsDataArray = [AllItemsData()]

After adding some data, now I want to store it into user defaults.

I did it this way:

AllItemsDataArray.removeFirst()

let archivedArray = NSKeyedArchiver.archivedData(withRootObject: All_ItemsDataArray)
            print(archivedArray)
            preference.set(archivedArray, forKey: allItemsDataKey)

But the error is like:

ios[1540:537869] -[_SwiftValue encodeWithCoder:]: unrecognized selector sent to instance 0x15d1e200

The values in the array just before the crash happens is:

AllItemsData(DSTBID: GGGGGGGGGGGG, CCAS: , BCAS: )
AllItemsData(DSTBID: HHHHHHHHHHHH, CCAS: , BCAS: )

yeah :( its a pity that a struct never conform to NSCoding - i am also looking to a nice solution for this - how to save and restor a struct (and nested struct) from and to UserDefaults — muescha, Jan 31 '17 at 17:37
on struct you get a `error: non-class type 'AllItemsData' cannot conform to class protocol 'NSCoding'` so you never have a chance to implement `NSCoding` :( — muescha, Jan 31 '17 at 17:39

Grzegorz Krukowski · Answer 1 · 2017-02-01T11:39:16.727

2

You need to implement NSCoding protocol for you object, and use class instead of struct

class AllItemsData: NSObject, NSCoding {
    var DSTBID: String!
    var CCAS: String!
    var BCAS: String!

    required convenience init?(coder decoder: NSCoder) {
        let DSTBID = decoder.decodeObjectForKey("DSTBID") as? String,
        let CCAS = decoder.decodeObjectForKey("CCAS") as? String,
        let BCAS = decoder.decodeObjectForKey("BCAS") as? [String]

        self.init(
            DSTBID: DSTBID,
            CCAS: CCAS,
            BCAS: BCAS
        )
    }

    func encodeWithCoder(coder: NSCoder) {
        coder.encodeObject(self.DSTBID, forKey: "DSTBID")
        coder.encodeObject(self.CCAS, forKey: "CCAS")
        coder.encodeInt(Int32(self.BCAS), forKey: "BCAS")
    }
}

edited Feb 01 '17 at 11:39

answered Jan 31 '17 at 16:53

Grzegorz Krukowski

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you forget to say that he need to change it into a class. mot anymore by value - now by reference. – muescha Feb 01 '17 at 01:43
You have the wrong signature if this is supposed to be Swift 3. – rmaddy Feb 08 '17 at 20:44
Yeah for swift3 it should be "encode(with coder: NSCoder)" – Grzegorz Krukowski Feb 08 '17 at 22:09

Save Custom Dictionary to User default

1 Answers1