Firebase Location to Maps - swift

Question

I am trying to add my locations values from firebase and turn them into annotation within my app. This is the code I have at the minute which is not working! Looking for a helping hand, feel like I am very close to getting this right but I have hit a mind block!
import UIKit
import Firebase
import MapKit
class ViewController: UIViewController {
#IBOutlet weak var mapView: MKMapView!
let locationsRef = FIRDatabase.database().reference(withPath: "locations")
override func viewDidLoad() {
super.viewDidLoad()
locationsRef.observe(.value, with: { snapshot in
for item in snapshot.children {
guard let locationData = item as? FIRDataSnapshot else { continue }
let locationValue = locationData.value as! [String: Any]
let location = CLLocationCoordinate2D(latitude: locationValue["lat"] as! Double, longitude: locationValue["lng"] as! Double)
let name = locationValue["name"] as! String
self.addAnnotation(at: location, name: name)
}
})
}
func addAnnotation(at location: CLLocationCoordinate2D, name: String) {
// add that annotation to the map
let annotation = MKPointAnnotation()
annotation.title = location["name"] as? String
annotation.coordinate = CLLocationCoordinate2D(latitude: location["latitude"] as! Double, longitude: location["lonitude"] as! Double)
mapView.addAnnotation(annotation)
}
}
My code is now working but I am getting this issue:
Could not cast value of type "NSTaggedPointerString' (0x10a708d10) to 'NSNumber' (0x109d10488).
Relating to this line of code:
let location = CLLocationCoordinate2D(latitude: locationValue["lat"] as! Double, longitude: locationValue["lng"] as! Double)
I have read something about converting a string to double but there is no string in this line? Can anybody help please?
Updated Code Subtitle
Subtitle
Update Error
Error

Answer 1

You are most likely storing the coordinates as String objects in your Firebase database. That's the most common reason that would cause that error. In that case, try the following
let lat = Double(locationValue["lat"] as! String)
let lng = Double(locationValue["lng"] as! String)
let location = CLLocationCoordinate2D(latitude: lat, longitude: lng)
Update
Some location entries of your database are stored as String objects, others as floating point numbers. You should have a consistent structure (i.e all of them be strings or doubles).
Either way, here's a solution for your error:
var location: CLLocationCoordinate2D!
if let lat = locationValue["lat"] as? String {
// stored as String
let lng = Double(locationValue["lng"] as! String)!
location = CLLocationCoordinate2D(latitude: Double(lat)!, longitude: lng)
}
else {
// stored as a floating point number
let lat = locationValue["lat"] as! Double
let lng = locationValue["lng"] as! Double
location = CLLocationCoordinate2D(latitude: lat, longitude: lng)
}
EDIT 2
Just remove the let here