Userdefaults can not retrieve custom Struct in Share Extension

Question

I have an App and also a Share Extension . Between them I share data via UserDefaults . But it stopped working all of a sudden. Only bools or Strings can now be retrieved inside the Share Extension but when trying to retrieve a Custom Struct it is always returning nil .

Custom Struct getter/setter in UserDefaults :

//MARK: dataSourceArray
func setDataSourceArray(data: [Wishlist]?){
    set(try? PropertyListEncoder().encode(data), forKey: Keys.dataSourceKey)
    synchronize()
}


func getDataSourceArray() -> [Wishlist]? {
    if let data = self.value(forKey: Keys.dataSourceKey) as? Data {
        do {
            _ = try PropertyListDecoder().decode(Array < Wishlist > .self, from: data) as [Wishlist]
        } catch let error {
            print(error)
        }
        if let dataSourceArray =
            try? PropertyListDecoder().decode(Array < Wishlist > .self, from: data) as[Wishlist] {
                return dataSourceArray
            } 
    }
    return nil
}

I am calling it like this inside my Extension as well as in my Main App:

   if let defaults = UserDefaults(suiteName: UserDefaults.Keys.groupKey) {
        if let data = defaults.getDataSourceArray() {
            print("working")
        } else {
            print("error getting datasourceArray")
        }
    }

This is printing "working" in the Main App but "error getting datasourceArray" in my Extension . I don't understand the issue, especially because simple Bool-Getter are working also from my Share Extension, the issue is only with the Custom Struct .

What am I missing here?

Wishlist Struct:

import UIKit

enum PublicState: String, Codable {
    case PUBLIC
    case PUBLIC_FOR_FRIENDS
    case NOT_PUBLIC
}

struct Wishlist: Codable {
    var id: String
    var name: String
    var image: UIImage
    var wishes: [Wish]
    var color: UIColor
    var textColor: UIColor
    var index: Int
    var publicSate: PublicState

    enum CodingKeys: String, CodingKey {
        case id, name, image, wishData, color, textColor, index, isPublic, isPublicForFriends, publicSate
    }

    init(id: String, name: String, image: UIImage, wishes: [Wish], color: UIColor, textColor: UIColor, index: Int, publicSate: PublicState) {
        self.id = id
        self.name = name
        self.image = image
        self.wishes = wishes
        self.color = color
        self.textColor = textColor
        self.index = index
        self.publicSate = publicSate
    }

    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        id = try values.decode(String.self, forKey: .id)
        name = try values.decode(String.self, forKey: .name)
        wishes = try values.decode([Wish].self, forKey: .wishData)
        color = try values.decode(Color.self, forKey: .color).uiColor
        textColor = try values.decode(Color.self, forKey: .textColor).uiColor
        index = try values.decode(Int.self, forKey: .index)
        publicSate = try values.decode(PublicState.self, forKey: .publicSate)

        let data = try values.decode(Data.self, forKey: .image)
        guard let image = UIImage(data: data) else {
            throw DecodingError.dataCorruptedError(forKey: .image, in: values, debugDescription: "Invalid image data")
        }
        self.image = image
    }

    func encode(to encoder: Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encode(id, forKey: .id)
        try container.encode(name, forKey: .name)
        try container.encode(wishes, forKey: .wishData)
        try container.encode(Color(uiColor: color), forKey: .color)
        try container.encode(Color(uiColor: textColor), forKey: .textColor)
        try container.encode(index, forKey: .index)
        try container.encode(image.pngData(), forKey: .image)
        try container.encode(publicSate, forKey: .publicSate)
    }
}

Update

This is the part where it fails:

if let data = self.value(forKey: Keys.dataSourceKey) as? Data

Is there any way to catch an error ?

I also found out that this feature is actually working for other users. The app is live: https://apps.apple.com/de/app/wishlists-einfach-w%C3%BCnschen/id1503912334

But it is not working for me? I deinstalled the app, downloaded it from the App Store but it is still not working.

Answer 1

I had the same problem but with another type of extension. Hope it works for you too.

1. Create a file you share between the two targets and put the following code there:

//MARK: - Model
struct WishlistStruct: Codable {
//your wishlist struct, I'll assume you'll have a name and some items
  var name : String
    var items : [String]
}
typealias Wishlist = WishlistStruct

//MARK: - Defaults
let sharedUserdefaults = UserDefaults(suiteName: SharedDefault.suitName)
struct SharedDefault {
    static let suitName = "yourAppGroupHere"
    
    struct Keys{
        static let WishlistKey = "WishlistKey"
       
    }
}

var myWishlist: [Wishlist] {
   get {
    if let data = sharedUserdefaults?.data(forKey: SharedDefault.Keys.WishlistKey) {
            let array = try! PropertyListDecoder().decode([Wishlist].self, from: data)
        return array
    } else{
        //Here you should return an error but I didn't find any way to do that so I put this code which hopefully will never be executed
    return sharedUserdefaults?.array(forKey: SharedDefault.Keys.WishlistKey) as? [Wishlist] ?? [Wishlist]()
    }
   } set {
       
   }
}

2. Now, whenever you need to retrieve the struct, both in app and extension, use the following code:

 var wishlist  : [Wishlist] = []
 var currentWishlist = myWishlist

//In your viewDidLoad call
wishlist.append(contentsOf: myWishlist)

3. To edit the data inside of your wishlist use the following code

 wishlist.append(Wishlist(name: "wishlist", items: ["aaa","bbb","ccc"]))
        currentWishlist.append(Wishlist(name: "wishlist", items: items: ["aaa","bbb","ccc"]))
        if let data = try? PropertyListEncoder().encode(currentWishlist) {
            sharedUserdefaults?.set(data, forKey: SharedDefault.Keys.WishlistKey)
        }

Let me know if you need more clarifications

Answer 2

Updated code to your struct. You should change some type of properties to yours(i remove some field for test).

import UIKit

enum PublicState: String, Codable {
    case PUBLIC
    case PUBLIC_FOR_FRIENDS
    case NOT_PUBLIC
}

struct Wishlist: Codable {
    var id: String = ""
    var name: String = ""
    var image: Data = Data()//TODO: use Data type
    var color: String = ""//TODO: change it to your class
//    var wish: //TODO: add this filed, i don't have it
    var textColor: String = "" //TODO: change it to your class
    var index: Int = 0
    var publicSate: PublicState = .PUBLIC

    enum CodingKeys: String, CodingKey {
        case id, name, image, color, textColor, index, publicSate
    }

    init() {}
    
    init(id: String, name: String, image: Data, color: String, textColor: String, index: Int, publicSate: PublicState) {
        self.id = id
        self.name = name
        self.image = image
        self.color = color
        self.textColor = textColor
        self.index = index
        self.publicSate = publicSate
    }
}

struct WishlistContainer: Codable {
    var list: [Wishlist] = []

    enum CodingKeys: String, CodingKey {
        case list
    }
}


class UserDefaultsManager {

//be sure your correctly setup your app groups
private var currentDefaults: UserDefaults = UserDefaults(suiteName: "put here your app group ID")!

private func getFromLocalStorage<T: Codable>(model: T.Type, key: String) -> T? {
    
    if let decoded = currentDefaults.object(forKey: key) as? String {
        
        guard let data = decoded.data(using: .utf8) else { return nil }
        
        if let product = try? JSONDecoder().decode(model.self, from: data) {
            return product
        }
    }
    
    return nil
}

private func saveToLocalStorage(key: String, encodedData: String) {
    currentDefaults.set(encodedData, forKey: key)
}

private func removeObject(key: String) {
    currentDefaults.removeObject(forKey: key)
}

var wishList: WishlistContainer? {
    set {
        guard let value = newValue else {
            removeObject(key: "wishList")
            return
        }
        
        let encoder = JSONEncoder()
        encoder.outputFormatting = .prettyPrinted
        
        guard let jsonData = try? encoder.encode(value) else { return }
        
        guard let jsonString = String(data: jsonData, encoding: .utf8) else { return }
        
        saveToLocalStorage(key: "wishList", encodedData: jsonString)
    }
    get {
        guard let value = getFromLocalStorage(model: WishlistContainer.self, key: "wishList") else {
            return nil
        }
        
        return value
    }
  }
}

//MARK: - Usage
let list: [Wishlist] = [Wishlist()]
let container: WishlistContainer = WishlistContainer(list: list)
UserDefaultsManager().wishList = container //set
UserDefaultsManager().wishList // get