swift: what is the correct way of working with current location

Question

I am quite new to swift and IOS development.

I would like to ask experienced members what is the correct way of creating mapview and tableview in one viewcontroller and populating them.

The logic of application is the following:

• get current location of user
• read plist file with POI coordinates
• for each POI run a function which calculates distance between user and point
• populate table with data from plist file plus newly calculated data.

Both mapview and tableview are in the same viewcontroller.

in viewDidLoad I am getting users location.

in viewwillappear I am running functions to read plist file and calculate distances between POIs and user.

Everything is working but it is not stable ... sometimes it might show user's location but table will be empty. So I doubt that I am doing everything correctly. Also probably it is not correct to put both map and table inside one class?

Update
Here is the code:

import UIKit
import MapKit
import CoreLocation


class MapViewController: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate, UITableViewDataSource, UITableViewDelegate  {

    @IBOutlet weak var theMapView: MKMapView!
    @IBOutlet weak var tableView: UITableView!
    

    var locationManager: CLLocationManager!
    var branches = [Branch]()
    

    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        locationManager = CLLocationManager()
        
        self.locationManager.requestAlwaysAuthorization()
        self.locationManager.requestWhenInUseAuthorization()
        
        if CLLocationManager.locationServicesEnabled() {
            locationManager.delegate = self
            locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
            locationManager.startUpdatingLocation()
        }
        
        
        
        
        
        
            tableView.dataSource = self
            tableView.delegate = self

        
            locationManager.startUpdatingLocation()
            locationManager.startUpdatingHeading()
       
        
            //mapview setup to show user location
            theMapView.delegate = self
            theMapView.showsUserLocation = true
            theMapView.mapType = MKMapType(rawValue: 0)!
            theMapView.userTrackingMode = MKUserTrackingMode(rawValue: 2)! 
    }
    

    
    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)

        readFromPlist()

    }

    
    
    
 
    
    //MARK: UITableView methods
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return branches.count
    }

    
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell: MapCustomCell = tableView.dequeueReusableCellWithIdentifier("mapCell") as! MapCustomCell
        let brnch = branches[indexPath.row]
        cell.mapSetupCell(brnch.cityName, AddressLabel: brnch.address, DistanceLabel: brnch.distance)
        return cell
    }


    
    //MARK: FUNC TO CALCULATE DISTANCE
    func calculateDistance (lat1 lat1: Double, lon1: Double, lat2: Double, lon2: Double) -> String {
        
        return "100km"
    }
    
    
    
    func locationManager (manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
       
        let myCoordinates = locations.last
        let myLat = myCoordinates!.coordinate.latitude
        let myLong = myCoordinates!.coordinate.longitude
        
        let myCoordinates2D = CLLocationCoordinate2DMake(myLat, myLong)
        
        let myLatDelta = 0.10
        let myLongDelta = 0.10
        let mySpan = MKCoordinateSpanMake(myLatDelta, myLongDelta)
        
        let myRegion = MKCoordinateRegion(center: myCoordinates2D, span: mySpan)
        
        theMapView.setRegion(myRegion, animated: true)
        
        let myAnno = MKPointAnnotation()
        myAnno.coordinate = myCoordinates2D
        
        self.locationManager.stopUpdatingLocation()
    }


    func locationManager(manager: CLLocationManager, didFailWithError error: NSError) {
        print("error:" + error.localizedDescription)
    }
    
    
    
    func readFromPlist() {
        
        //read plist file to extract banks coordinates
        let path = NSBundle.mainBundle().pathForResource("poi", ofType: "plist")
        let POIarrays = NSArray(contentsOfFile: path!)
        
        for arr in POIarrays! {
            
            var ctName : String!
            var brnchAddress : String!
            var wrkngHours : String!
            var lat : Double!
            var long : Double!
            
            ctName  = arr.objectForKey("cityName")! as! String
            brnchAddress  = arr.objectForKey("address")! as! String
            wrkngHours  = arr.objectForKey("workingHours")! as! String
            lat  = Double(arr.objectForKey("latitude")! as! String)
            long  = Double(arr.objectForKey("longitude")! as! String)

                
                let latitude: CLLocationDegrees = lat
                let longitude : CLLocationDegrees = long
                
                let bankLocation : CLLocationCoordinate2D = CLLocationCoordinate2DMake(latitude, longitude)
                
                
                let annotation = MKPointAnnotation()
                annotation.coordinate = bankLocation
                annotation.title = bnkName
                annotation.subtitle = brnchAddress
                
                self.theMapView.addAnnotation(annotation)
                
                
                let myLatitude = self.locationManager.location?.coordinate.latitude
                let myLongitude = self.locationManager.location?.coordinate.longitude
                
                if myLatitude != nil {
                    
                    let dist = calculateDistance(lat1: latitude, lon1: longitude, lat2: myLatitude!, lon2: myLongitude!)
                
                    let b = Branch(cityName: ctName!, address: brnchAddress!, distance: dist)
                
                    branches.append(b)
            
            }
        }

    }

    
}

Sometimes I got an error

"error:The operation couldn’t be completed. (kCLErrorDomain error 0.)"

and current location doesn't appear on my map.