[Swift] Realm data migration

 

 

class AppDelegate: UIResponder, UIApplicationDelegate {
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {



func migrate(){

                let config = Realm.Configuration(

                    // Set the new schema version. This must be greater than the previously used

                    // version (if you've never set a schema version before, the version is 0).

                    schemaVersion: 1,

                    

                    // Set the block which will be called automatically when opening a Realm with

                    // a schema version lower than the one set above

                    migrationBlock: { migration, oldSchemaVersion in

                        

                        if oldSchemaVersion < 1 {

                            migration.enumerateObjects(ofType: Item.className()) { oldObject, newObject in

                                newObject?["dateCreated"] = Date()

                            }

                        }

                }

                )

                Realm.Configuration.defaultConfiguration = config
                
                }

            }