如何設置MGLAnnotationView作爲sourceView爲酥料餅

Question

我想要做的就是呈現酥料餅與annotation作爲其源視圖/錨

使用委派功能didSelect annotationView我應該能夠做到這一點，但它似乎並沒有運行。 現在我只是通過didSelect註釋提出我酥料餅，並設置sourceView到導航欄，只是爲了顯示它的地方......

FYI： 我已經實現了Mapbox SDK到項目。 我沒有問題使用MapKit執行相同的任務。

有沒有人有什麼想法我可以做到這一點？

下面的代碼片段：

import UIKit 
import Mapbox 

class ViewController: UIViewController, MGLMapViewDelegate, UIPopoverPresentationControllerDelegate { 

@IBOutlet var theMap: MGLMapView! 

override func viewDidLoad() { 
    super.viewDidLoad() 

    theMap.delegate = self 

    let point = MGLPointAnnotation() 
    point.coordinate = CLLocationCoordinate2D(latitude: 55.6, longitude: 13.0) 
    point.title = "Some place" 
    point.subtitle = "Malmö, Sweden" 
    theMap.addAnnotation(point) 
} 

func mapView(_ mapView: MGLMapView, didSelect annotationView: MGLAnnotationView) { 
    print("annotation view: ", annotationView) 
    // this method doesn't seem to get called at all... 
    // but ideally this is the place to present the popover. 
} 

func mapView(_ mapView: MGLMapView, didSelect annotation: MGLAnnotation) { 
    print("annotation: ", annotation) 
    // present the popover 
    presentPopover() 
} 

func presentPopover(){ 
    let popover = storyboard?.instantiateViewController(withIdentifier: "MyCalloutVC") as! MyCallout 

    popover.modalPresentationStyle = UIModalPresentationStyle.popover 
    popover.popoverPresentationController?.backgroundColor = UIColor.white 
    popover.popoverPresentationController?.delegate = self 

    // I would like to set the source anchor to the selected annotation view. 
    popover.popoverPresentationController?.sourceView = UINavigationBar() // set to nav bar for now... 
    popover.popoverPresentationController?.permittedArrowDirections = .any 
    // popover size set in MyCallout 
    self.present(popover, animated: true) 
    } 
} 

Answer 1

的功能不被調用，因爲沒有標註視圖，可以選擇的。這意味着您只需添加點註釋而不是註釋視圖。因此您必須這樣做： 當您添加註釋時，func mapView(_ mapView: MGLMapView, viewFor annotation: MGLAnnotation) -> MGLAnnotationView? {}被調用，您可以在其中定義註釋視圖並將其返回。然後選定的函數將被調用。看看示例代碼：https://www.mapbox.com/ios-sdk/examples/annotation-views/

import Mapbox 

// Example view controller 
class ViewController: UIViewController, MGLMapViewDelegate { 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     let mapView = MGLMapView(frame: view.bounds) 
     mapView.autoresizingMask = [.flexibleWidth, .flexibleHeight] 
     mapView.styleURL = MGLStyle.darkStyleURL(withVersion: 9) 
     mapView.tintColor = .lightGray 
     mapView.centerCoordinate = CLLocationCoordinate2D(latitude: 0, longitude: 66) 
     mapView.zoomLevel = 2 
     mapView.delegate = self 
     view.addSubview(mapView) 

     // Specify coordinates for our annotations. 
     let coordinates = [ 
      CLLocationCoordinate2D(latitude: 0, longitude: 33), 
      CLLocationCoordinate2D(latitude: 0, longitude: 66), 
      CLLocationCoordinate2D(latitude: 0, longitude: 99), 
     ] 

     // Fill an array with point annotations and add it to the map. 
     var pointAnnotations = [MGLPointAnnotation]() 
     for coordinate in coordinates { 
      let point = MGLPointAnnotation() 
      point.coordinate = coordinate 
      point.title = "\(coordinate.latitude), \(coordinate.longitude)" 
      pointAnnotations.append(point) 
     } 

     mapView.addAnnotations(pointAnnotations) 
    } 

    // MARK: - MGLMapViewDelegate methods 

    // This delegate method is where you tell the map to load a view for a specific annotation. To load a static MGLAnnotationImage, you would use `-mapView:imageForAnnotation:`. 
    func mapView(_ mapView: MGLMapView, viewFor annotation: MGLAnnotation) -> MGLAnnotationView? { 
     // This example is only concerned with point annotations. 
     guard annotation is MGLPointAnnotation else { 
      return nil 
     } 

     // Use the point annotation’s longitude value (as a string) as the reuse identifier for its view. 
     let reuseIdentifier = "\(annotation.coordinate.longitude)" 

     // For better performance, always try to reuse existing annotations. 
     var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: reuseIdentifier) 

     // If there’s no reusable annotation view available, initialize a new one. 
     if annotationView == nil { 
      annotationView = CustomAnnotationView(reuseIdentifier: reuseIdentifier) 
      annotationView!.frame = CGRect(x: 0, y: 0, width: 40, height: 40) 

      // Set the annotation view’s background color to a value determined by its longitude. 
      let hue = CGFloat(annotation.coordinate.longitude)/100 
      annotationView!.backgroundColor = UIColor(hue: hue, saturation: 0.5, brightness: 1, alpha: 1) 
     } 

     return annotationView 
    } 

    func mapView(_ mapView: MGLMapView, annotationCanShowCallout annotation: MGLAnnotation) -> Bool { 
     return true 
    } 
} 

// 
// MGLAnnotationView subclass 
class CustomAnnotationView: MGLAnnotationView { 
    override func layoutSubviews() { 
     super.layoutSubviews() 

     // Force the annotation view to maintain a constant size when the map is tilted. 
     scalesWithViewingDistance = false 

     // Use CALayer’s corner radius to turn this view into a circle. 
     layer.cornerRadius = frame.width/2 
     layer.borderWidth = 2 
     layer.borderColor = UIColor.white.cgColor 
    } 

    override func setSelected(_ selected: Bool, animated: Bool) { 
     super.setSelected(selected, animated: animated) 

     // Animate the border width in/out, creating an iris effect. 
     let animation = CABasicAnimation(keyPath: "borderWidth") 
     animation.duration = 0.1 
     layer.borderWidth = selected ? frame.width/4 : 2 
     layer.add(animation, forKey: "borderWidth") 
    } 
}