Handling Asynchronous Call by Alamofire - ios

Question

I am using Swift 3 with XCode 8
I am pretty new to IOS development and using Swift. I am currently having a problem where some required code does not run after the asynchronous call has successfully been completed.
In my constants file:
typealias DownloadComplete = () -> ()
In my WeatherVC.swift file:
var currentWeather = CurrentWeather()
override func viewDidLoad() {
super.viewDidLoad()
TableView.delegate = self
TableView.dataSource = self
currentWeather.downloadWeatherDetails{
//setup UI to load downloaded data
print("Done 2")
self.updateMainUI()
}
}
In my CurrentWeather.swift class:
func downloadWeatherDetails(completed: #escaping DownloadComplete){
//Alamofire download
let currentWeatherURL = URL(string: CURRENT_WEATHER_URL)!
Alamofire.request(currentWeatherURL).responseJSON { response in
let result = response.result
if let dict = result.value as? Dictionary<String, AnyObject>{
if let name = dict["name"] as? String{
self._cityName = name.capitalized
print(self._cityName)
}
if let weather = dict["weather"] as? [Dictionary<String, AnyObject>]{
if let main = weather[0]["main"] as? String{
self._weatherType = main.capitalized
print(self._weatherType)
}
}
if let main = dict["main"] as? Dictionary<String, AnyObject>{
if let currentTemperature = main["temp"] as? Double {
let kelvinToCelsius = currentTemperature - 273.15
self._currentTemp = kelvinToCelsius
print(self._currentTemp)
}
}
}
print("Done 1")
}
completed() //Make sure to tell download is done
}}
When Executing the code, "Done 2" is being printed out first, before "Done 1", when I want it to be the other way around.
How can I fix this? (FYI: Following Weather App Tutorial on Udemy)

Answer 1

Update: It was just simply moving completed inside the responseJSON closure.