Firestore instantiate objects with data recover Swift 5.0 - arrays

Question

I get all the data from my snapshot and create an object list with the data.
My problem: I can't return a list to use my objects in other code functions.
I tried to browse my list to create using my snapshot to implement a new list of objects declared above in my code.
class ViewController: UIViewController {
lazy var usersCollection = Firestore.firestore().collection("ship")
var ships: [MyShip] = []
override func viewDidLoad() {
super.viewDidLoad()
getUsers()
print(ships.count)
}
The getData function:
func getUsers() {
usersCollection.getDocuments { (snapshot, _) in
//let documents = snapshot!.documents
// try! documents.forEach { document in
//let myUser: MyUser = try document.decoded()
//print(myUser)
//}
let myShip: [MyShip] = try! snapshot!.decoded()
// myShip.forEach({print($0)})
for elt in myShip {
print(elt)
self.ships.append(elt)
}
print(self.ships[1].nlloyds)
}
}
result console
Result in the console:
- my list is not filled return 0
- I print the objects well and I print them well
- I print the ships object[1].nloyds = 555 well in the function

Answer 1

Your print(ships.count) call in viewDidLoad is printing an empty array because the .getDocuments() method is asynchronous. Try writing getUsers as a closure like this:
func getUsers(completion: #escaping ([MyShip]) -> Void) {
usersCollection.getDocuments { (snapshot, _) in
let myShip: [MyShip] = try! snapshot!.decoded()
completion(myShip)
}
}
and then use it in the viewDidLoad method like this:
override func viewDidLoad() {
super.viewDidLoad()
getUsers() { shipsFound in
self.ships = shipsFound
print(self.ships.count)
}
}