Place multiple markers on MKMapView from Firebase Database - ios

Question

I'm creating an iOS app that uses Apple Maps to display markers for Garage/Yard Sales in the local area. So far I've been able to figure out how to place one marker on Apple Maps from the Firebase Database, but I'm not sure how to do it with multiple markers. I've done similar tasks using cells to display different content in a UITableView from Firebase Database but this is my first time doing it map-wise. I was reading an article here that showed how it was possible with JSON data, but due to the fact the marker information will be live, it wouldn't be possible that way for my app. What would be the best way to add multiple markers to a MKMapView?
Snippet from ViewController (Only setup for one marker)
Database.database().reference().child("posts").observeSingleEvent(of: .value, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let artwork = Artwork(title: dictionary["title"] as! String,
locationName: dictionary["location"] as! String,
discipline: dictionary["category"] as! String,
coordinate: CLLocationCoordinate2D(latitude: dictionary["lat"] as! Double, longitude: dictionary["long"] as! Double))
self.mapView.addAnnotation(artwork)
}
})
Artwork.swift
class Artwork: NSObject, MKAnnotation {
let title: String?
let locationName: String
let discipline: String
let coordinate: CLLocationCoordinate2D
init(title: String, locationName: String, discipline: String, coordinate: CLLocationCoordinate2D) {
self.title = title
self.locationName = locationName
self.discipline = discipline
self.coordinate = coordinate
super.init()
}
var subtitle: String? {
return locationName
}
}

Answer 1

I was able to figure out a way to this thanks to the link #kosuke-ogawa posted.
Snippet within ViewController.swift
override func viewDidLoad() {
super.viewDidLoad()
let ref = Database.database().reference()
let postsRef = ref.child("posts")
postsRef.observeSingleEvent(of: .value, with: { (snapshot) in
for snap in snapshot.children {
let postSnap = snap as! DataSnapshot
if let dict = postSnap.value as? [String:AnyObject] {
let title = dict["title"] as! String
let locationName = dict["location"] as! String
let discipline = dict["category"] as! String
let coordinate = CLLocationCoordinate2D(latitude: dict["lat"] as! Double, longitude: dict["long"] as! Double)
let artwork = Artwork(title: title, locationName: locationName, discipline: discipline, coordinate: coordinate)
self.mapView.addAnnotation(artwork)
}
}
})
}
If there is a cleaner way to do this feel free to edit my code to help others in the future.

Answer 2

for multiple place marker on MKMapView you can take array of ArtWork That you Have created, please try this bellow solution
var arrArtworks: [Artwork] = []
override func viewDidLoad() {
super.viewDidLoad()
intializeData()
PlaceMarker()
}
func intializeData(){
Database.database().reference().child("posts").observeSingleEvent(of: .value, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let artwork = Artwork(title: dictionary["title"] as! String,
locationName: dictionary["location"] as! String,
discipline: dictionary["category"] as! String,
coordinate: CLLocationCoordinate2D(latitude: dictionary["lat"] as! Double, longitude: dictionary["long"] as! Double))
arrArtworks.append(Artwork)
}
})
}
func PlaceMarker() {
mapView.addAnnotations(arrArtworks)
}

Answer 3

For example, you can use for loop:
Database.database().reference().child("posts").observeSingleEvent(of: .value, with: { (snapshot) in
for child in snapshot.children.allObjects as! [DataSnapshot] {
if let dictionary = child.value as? [String: AnyObject] {
let artwork = Artwork(title: dictionary["title"] as! String,
locationName: dictionary["location"] as! String,
discipline: dictionary["category"] as! String,
coordinate: CLLocationCoordinate2D(latitude: dictionary["lat"] as! Double, longitude: dictionary["long"] as! Double))
self.mapView.addAnnotation(artwork)
}
}
})
cf. http://takeip.com/swift-3-firebase-to-mapkit.html