How do I access an instance of a class in Swift - ios

Question

I have a user class defined in UserClass.swift like this:
class User {
var id:Int
var name:String
var phone:String
var email:String
init(id:Int, name:String, phone:String, email:String){
self.id = id
self.name = name
self.phone = phone
self.email = email
}
}
In my ProfileViewController I call a method on viewDidLoad called getUserData.
class ProfileViewController: UIViewController {
#IBOutlet weak var userNameLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
getUserData { myUser in
self.userNameLabel.text = myUser.name
}
}
getUserData pings my API and then instantiates and instance of the User class.
func getUserData(completionHandler:(User)->()) {
Alamofire.request(.GET, "apiEndPoint")
.responseJSON { response in
if let value: AnyObject = response.result.value {
let userData = JSON(value)
let userName = userData["name"].string!
let userId = userData["id"].int!
let userPhone = userData["phone"].string!
let userEmail = userData["email"].string!
let myUser = User(id:userId, name:userName, phone:userPhone, email:userEmail)
print("user: \(myUser.name)")
completionHandler(myUser)
}
}
}
I then pass that instance with a callback to the ProfileViewController so that I can update a label. This works great.
The problem is that now I want to look at a different property of the User instance myUser in a different place, outside of the callback. Eventually I want to get the user's id, but for now I'm just trying to access the instance at all, so I'm looking again at updating a label with the user's name:
class MyActivitiesViewController: UIViewController {
#IBOutlet weak var myActTempLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
self.myActTempLabel.text = myUser.name
}
}
This is giving me an error of Use of unresolved identifier 'myUser'. How do I access the instance of User that I already created?

Answer 1

You should keep a reference to the User object in a singleton in order to access it every where. Basically in cases like this you have a singleton class called say CurrentUser
class CurrentUser {
static var sharedInstance = CurrentUser()
var user:User?
}
Then in your network call or perhaps in the completion handler of the first view controller you where you know the first time the user is obtained you can set the User instance to the CurrentUser singleton.
CurrentUser.sharedInstance.user = myUser
Later you can use CurrentUser.sharedInstance.user in all the places where you want to get the user details.

Answer 2

it's very simple . just create a ref of User in your class and assign myUser to it
like:
class ProfileViewController: UIViewController {
var user: User?
#IBOutlet weak var userNameLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
getUserData { myUser in
self.user = myUser
self.userNameLabel.text = myUser.name
}
}

Answer 3

your instance myUser is just existed in your block. You need to create a variable to store this
class ProfileViewController: UIViewController {
var user:User?
#IBOutlet weak var userNameLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
getUserData { myUser in
self.userNameLabel.text = myUser.name
user = myUser
}
}
now you can use "user" property to access outside your block