How to save an Array with Objects to UserDefaults

Question

My Object conforms to the new Swift 4 Codeable protocol. How to save an array of these Objects in UserDefaults?

struct MyObject: Codeable {
    var name: String
    var something: [String]
}

myObjectsArray = [MyObject]() // filled with objects
UserDefaults.standard.set(myObjectsArray, forKey: "user_filters")

Error

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Attempt to insert non-property list object

Answer 1

Whew, I got it working:

Here is the Swift 4 Syntax to save an Array with Codeable Objects:

My solution is to encode it as a JSON Object and save that:

static var getAllObjects: [MyObject] {
      let defaultObject = MyObject(name: "My Object Name")
      if let objects = UserDefaults.standard.value(forKey: "user_objects") as? Data {
         let decoder = JSONDecoder()
         if let objectsDecoded = try? decoder.decode(Array.self, from: objects) as [MyObject] {
            return objectsDecoded
         } else {
            return [defaultObject]
         }
      } else {
         return [defaultObject]
      }
   }

 static func saveAllObjects(allObjects: [MyObject]) {
      let encoder = JSONEncoder()
      if let encoded = try? encoder.encode(allObjects){
         UserDefaults.standard.set(encoded, forKey: "user_objects")
      }
 }