Saving UIColor within Struct Array to UserDefaults

Question

I have tried to implement the solution by Vadian here: Make UIColor Codable

But I am getting an error that I haven't been able to overcome.

Here is my implementation of the above mention solution:

struct Color : Codable {
    var red : CGFloat = 0.0, green: CGFloat = 0.0, blue: CGFloat = 0.0, alpha: CGFloat = 0.0

    var uiColor : UIColor {
        return UIColor(red: red, green: green, blue: blue, alpha: alpha)
    }

    init(uiColor : UIColor) {
        uiColor.getRed(&red, green: &green, blue: &blue, alpha: &alpha)
    }
}

struct Tasting: Codable {

    private enum CodingKeys: String, CodingKey { case id, title, color, textColor, notes }

    var id: Int
    var title: String
    var color : UIColor
    var textColor : UIColor
    var notes: String

    init(id: Int, title: String, color : UIColor, textColor : UIColor, notes: String) {
        self.id = id
        self.title = title
        self.color = color
        self.textColor = textColor
        self.notes = notes
    }
    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        id = try container.decode(Int.self, forKey: .id)
        title = try container.decode(String.self, forKey: .title)
        color = try container.decode(Color.self, forKey: .color).uiColor
        textColor = try container.decode(Color.self, forKey: .textColor).uiColor
        notes = try container.decode(String.self, forKey: .notes)

    }

    public func encode(to encoder: Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encode(id, forKey: .id)
        try container.encode(title, forKey: .title)
        try container.encode(Color(uiColor: color), forKey: .color)
        try container.encode(Color(uiColor: color), forKey: .textColor)
        try container.encode(notes, forKey: .notes)
    }
}

And here:

//Encodes UIColor so it can be saved
        let tastings = [
            Tasting(id: 0, title: "(Delete this row after you add your first tasting!)", color: .green, textColor: .black, notes: "Add notes here.")
        ]
        do {
            let data = try JSONEncoder().encode(tastings)
            print(String(data: data, encoding: .utf8)!)
            let newTastings = try JSONDecoder().decode(Tasting.self, from: data)
            print("newTastings \(newTastings)")
        } catch {
            print("newTastings \(error)")
        }

Then saving it to UserDefaults.


        //Saves new brand to device memory
        let savedTastings = tastings
        UserDefaults.standard.set(savedTastings, forKey: "tastings")

These are the errors I am getting:

newTastings typeMismatch(Swift.Dictionary<Swift.String, Any>, Swift.DecodingError.Context(codingPath: [], debugDescription: "Expected to decode Dictionary<String, Any> but found an array instead.", underlyingError: nil))

2019-07-25 11:38:05.909711-0700 WhiskyTasting[10601:3581697] [User Defaults] Attempt to set a non-property-list object (
    "WhiskyTasting.Tasting(id: 0, title: \"(Delete this row after you add your first tasting!)\", color: UIExtendedSRGBColorSpace 0 1 0 1, textColor: UIExtendedGrayColorSpace 0 1, notes: \"Add notes here.\")"
) as an NSUserDefaults/CFPreferences value for key tastings
2019-07-25 11:38:05.910207-0700 WhiskyTasting[10601:3581697] *** 

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Attempt to insert non-property list object (
    "WhiskyTasting.Tasting(id: 0, title: \"(Delete this row after you add your first tasting!)\", color: UIExtendedSRGBColorSpace 0 1 0 1, textColor: UIExtendedGrayColorSpace 0 1, notes: \"Add notes here.\")"
) for key tastings'

I hope y'all see a simple typo that I'm missing. Been struggling with variations of this for a few days.

https://stackoverflow.com/q/46522572/2303865\ – Leo Dabus Jul 25 '19 at 19:04 — Leo Dabus, Jul 25 '19 at 19:04

score 0 · Accepted Answer · answered Jul 25 '19 at 19:13

0

The errors are not related to my solution.

The first error tells you that the object is an array. Please read your code, tastings is clearly an array.
So you have to decode an array
```
let newTastings = try JSONDecoder().decode([Tasting].self, from: data)
```
The second error tells you that in your struct is a type which is not property list compliant. This type is UIColor. You cannot save Tasting instances to UserDefaults, but you can save JSON-/ or PropertyList-encoded Tasting instances.
```
 let data = try JSONEncoder().encode(tastings)
 UserDefaults.standard.set(data, forKey: "tastings")
```

answered Jul 25 '19 at 19:13

vadian

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Thanks! That solved the error. I knew it was some syntax that I missed. Now I just need to find the correct way to decode it when I recall the data from UserDefaults. This encode/decode is all new to me. First couple tries failed. I may return for a push if I hit a wall. – Freedlun Jul 25 '19 at 20:41
1

Do it just the opposite way: Load the data as `Data` and decode it as in the answer – vadian Jul 25 '19 at 21:22

Saving UIColor within Struct Array to UserDefaults

1 Answers1