Execute function on startup - ios

Question

I'm trying to develop an application for IOS using swift language that is a news for me. I want to fill a dictionary (tobaccoList) on the application startup. I have a csv file, so I take data from this file and than i fill the dictionary:
class DataManager{
var latitudes = Array<Double>()
var longitudes = Array<Double>()
var tobaccoList = Dictionary<Double, Tabacchino>()
init(){
if let url = NSURL(fileURLWithPath: "/Users/brunopistone/Developer/apptabacchi/LocationList_sorted.csv" , isDirectory: true) {
var error: NSErrorPointer = nil
if let csv = CSV(contentsOfURL: url, error: error) {
//put every tabbacchino in a Dictionary tobaccoList
let rows = csv.rows
let totalRows = rows.count
for var index = 1; index < totalRows; index++ {
let temp = csv.rows[index]
let tabacchino = Tabacchino(
name: temp["Name"]!, phone: temp["tnumber"]!, lat: NSString(string: temp["Latitude"]!).doubleValue, lon: NSString(string: temp["Longitude"]!).doubleValue
)
let keyGeo = NSString(string: temp["Latitude"]!).doubleValue
storeTobaccoShop(keyGeo, value: tabacchino)
var doubleLatitude = NSString(string: temp["Latitude"]!).doubleValue
var doubleLongitude = NSString(string: temp["Longitude"]!).doubleValue
storeLatitude(doubleLatitude)
storeLongitudes(doubleLongitude)
}
}
}
}
func storeTobaccoShop(key: Double, value: Tabacchino) {
self.tobaccoList[key] = value
}
In the viewController file of the home page i have:
class ViewController: UIViewController, CLLocationManagerDelegate {
let startFunction = DataManager()
let locationManager = CLLocationManager()
var latitude = Double()
var longitude = Double()
var tobaccoList = Dictionary<Double, Tabacchino>()
override func viewDidLoad() {
self.locationManager.delegate = self
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
self.locationManager.requestWhenInUseAuthorization()
locationManager.startUpdatingLocation()
tobaccoList = startFunction.getTobaccoList()
}
In the home page, I have a button that calls another view, and i want to pass the dictionary to the other view in order to use it, so I use this method:
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if segue.identifier == "tobaccoListSegue"{
let viewList = segue.destinationViewController as! ViewList
viewList.tabacchini = tobaccoList
}
}
The problem is, when i click on the button in order to call viewList, the application fills again the dictionary. What i want is to fill the dictionary only when I open the application.
Please help me fix this thing. Thanks

Answer 1

Put this line
let startFunction = DataManager()
Inside viewdidload() method.