从 Firebase 数据库在 MKMapView 上放置多个标记

Place multiple markers on MKMapView from Firebase Database

我正在创建一个 iOS 应用程序,该应用程序使用 Apple 地图显示本地 Garage/Yard 销售的标记。到目前为止,我已经能够弄清楚如何从 Firebase 数据库中在 Apple Maps 上放置一个标记,但我不确定如何使用多个标记来做到这一点。我已经完成了类似的任务,使用单元格在 Firebase 数据库的 UITableView 中显示不同的内容,但这是我第一次在地图上这样做。我正在阅读一篇文章 here,它展示了如何使用 JSON 数据,但由于标记信息将是实时的,我的应用程序不可能那样做。将多个标记添加到 MKMapView 的最佳方法是什么?

来自 ViewController 的片段(仅设置一个标记)

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
    }
}

对于 MKMapView 上的多个位置标记,您可以获取您创建的艺术品数组,请尝试以下解决方案

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)
}

例如,您可以使用 for 循环:

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)
    }
  }
})

比照。 http://takeip.com/swift-3-firebase-to-mapkit.html

多亏了 link @kosuke-ogawa 的帖子,我才找到解决这个问题的方法。

ViewController.swift

中的片段
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)
                }
            }
        })
    }

如果有更简洁的方法来执行此操作,请随时编辑我的代码以在将来帮助其他人。