Passing custom objects between two iOS Apps

Question

I need some help on something. I have two apps under my account.

I need to pass a custom object from App A to App B. How can I do this using app groups ?

I saw that using URL schemes is a old a way of doing it.

So what is the newest way of passing data two apps ?

Answer 1

IN YOUR APP A (SAVE OBJECT)

1. Under capabilities, Click "+" to add an App Group

2. In your Object Class, you need to extend the class you want to share to NSObject and NSCoding

   class Person : NSObject, NSCoding {
       var nom: String
       var prenom: String
   
       required init(name: String, prenom: String) {
          self.nom = name
          self.prenom = prenom
       }
   
       required init(coder decoder: NSCoder) {
           self.nom = decoder.decodeObject(forKey: "name") as? String ?? ""
           self.prenom = decoder.decodeObject(forKey: "prenom") as? String ?? ""
       }
       func encode(with coder: NSCoder) {
           coder.encode(nom, forKey: "nom")
           coder.encode(prenom, forKey: "prenom")
       }
   }
   

3. Save Data from your App A

   override func viewDidLoad() {
       super.viewDidLoad()
       // Do any additional setup after loading the view, typically from a nib.
       let person = Person(name: "Ugo", prenom: "Marinelli")
       saveData(person: person)
   }
   
   func saveData(person : Person){
       //Map Class to recognize it
       NSKeyedArchiver.setClassName("Person", for: Person.self)
   
       //Encode the object
       let personEncoded = NSKeyedArchiver.archivedData(withRootObject: person)
   
       //Push the object to the App Group
       UserDefaults(suiteName: "group.tag.testAppGroup")!.set(personEncoded, forKey: "FirstLaunch")
   }
   

IN YOUR APP B (GET OBJECT)

1. Add the same app group as the App A (see 1.1)

2. In the View controller you want to get the App A object :

   override func viewDidLoad() {
       super.viewDidLoad()
       // Do any additional setup after loading the view, typically from a nib.
   
       //Class Mapping
       NSKeyedUnarchiver.setClass(Person.self, forClassName: "Person")
   
       //Get The encoded data from App Group
       let personEncoded  = UserDefaults(suiteName: "group.tag.testAppGroup")!.object(forKey: "FirstLaunch") as! NSData
   
       //Decode to get our Person object
       let personDecoded = NSKeyedUnarchiver.unarchiveObject(with: personEncoded as Data) as? Person
   
       print(personDecoded?.prenom)
   }
   

Note that you need to implement your Person class in both file, the best practice would be to create your own framework with your model in it