swift - 将文本从 MKMarkerAnnotation 传递到不同的 View Controller

Question

当点击标记时，我试图将文本从我在 MKMapView 上的标记传递到不同的 View Controller 。我在网上阅读后尝试使用一种方法，但由于我将文本传递到的 View Controller 没有导航 Controller ，我认为它不会起作用。请注意，我还使用 Firebase 检索将显示在标记上的数据， View Controller 看起来很奇怪的原因是因为我使用的是 ISHPullUp。

视觉呈现:https://imgur.com/a/zEW64aY

来自 TopViewController 的代码(MKMapView 和 MKMarker 数据)

var mainTitle = ""

.

Database.database().reference().child("posts").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)
            }
        }
    })

.

extension TopViewController: MKMapViewDelegate {
    func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
        guard let annotation = annotation as? Artwork else { return nil }
        let identifier = "marker"
        var view: MKMarkerAnnotationView
        if let dequeuedView = mapView.dequeueReusableAnnotationView(withIdentifier: identifier)
            as? MKMarkerAnnotationView {
            dequeuedView.annotation = annotation
            view = dequeuedView
        } else {
            view = MKMarkerAnnotationView(annotation: annotation, reuseIdentifier: identifier)
            mainTitle = annotation.title!
        }
        return view
    }

    func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
        let myVC = storyboard?.instantiateViewController(withIdentifier: "bottom") as! BottomViewController // Didn't work
        myVC.stringPassed = mainTitle
        navigationController?.pushViewController(myVC, animated: true)
        print(mainTitle)
    }
}

来自 BottomViewController 的代码(我正在尝试将文本发送到的 View Controller )

var stringPassed = ""

override func viewDidLoad() {
    super.viewDidLoad()

    toplabel.text = stringPassed
}

来自 ViewController 的代码

class ViewController: ISHPullUpViewController {
    private func commonInit() {
        let storyBoard = UIStoryboard(name: "Main", bundle: nil)
        let contentVC = storyBoard.instantiateViewController(withIdentifier: "content") as! TopViewController
        let bottomVC = storyBoard.instantiateViewController(withIdentifier: "bottom") as! BottomViewController
        contentViewController = contentVC
        bottomViewController = bottomVC
        bottomVC.pullUpController = self
        contentDelegate = contentVC
        sizingDelegate = bottomVC
        stateDelegate = bottomVC
    }
}

Answer 1

你需要实现MKMapViewDelegate的didSelect委托(delegate)方法

func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
        if view.annotation is MKUserLocation {
            return
        }
        let ann = view.annotation as! Artwork
        let storyBoard = UIStoryboard(name: "Main", bundle: nil)
        let bottomVC = storyBoard.instantiateViewController(withIdentifier: "bottom") as! BottomViewController
        bottomViewController = bottomVC
        bottomVC.pullUpController = self
        sizingDelegate = bottomVC
        vc.stringPassed = ann.title
}

//

override func prepare(for segue: UIStoryboardSegue, sender: Any?){
    if segue.identifier == "bottom" {
      let nextScene =  segue.destination  as! BottomViewController 
      nextScene.stringPassed = sender as! String
    }
}

//

还可以使用 push 而不是 segue embed TopViewController inside a UINavigationController