ios - 如何更改 MGLPolyline 的颜色？

Question

如何更改 MGLPolyline 的颜色？我看过here但答案不起作用。我还尝试了一些其他代码，但它太依赖苹果 map 了。那么我怎样才能改变线条的颜色，并且最好还能够编辑线条的其他方面呢？波纹管是我相信我应该进行这些编辑的代码的地方，但我不是 100%。

        @objc func useButtonTap(_ sender: UIGestureRecognizer) {
        print("use tap button pressed")
        startButton.backgroundColor = UIColor(red: 1.0, green: 1.0, blue: 1.0, alpha: 0.9)
        useTrackButton.backgroundColor = UIColor(red: 1.0, green: 1.0, blue: 1.0, alpha: 0.9)

        locationManager?.stopUpdatingLocation()

        print(locationList, "<-- location manager array in use button")
        if locationList == [] {
            print("nothing was tracked")
        } else {

            var mapCoordinates: [CLLocationCoordinate2D] = []

            for locationT in locationList {
                print(locationT, "<-- locationT")
                print(locationT.coordinate.latitude, "<-- latitude")
                print(locationT.coordinate.longitude, "<-- longitude")

                let locationLatitude = locationT.coordinate.latitude
                let locationLongitude = locationT.coordinate.longitude

                print(locationLatitude, "lat")
                print(locationLongitude, " long")
                let newCoord = CLLocationCoordinate2D(latitude: locationLatitude, longitude: locationLongitude) // - (0.0001/2)
                print(newCoord, "<-- new coord")
                mapCoordinates.append(newCoord)//+ 0.0001

            }

            polyline = MGLPolyline(coordinates: mapCoordinates, count: UInt(mapCoordinates.count))
//            toCome = polyline
//            mapView.add(polyline)

            mapView.addAnnotation(polyline) //used to be jsut .add, changed in order to try anwser for color chaning of polyline

        }
    }

Answer 1

你必须使mapView.delegate = self

然后实现这个方法:

func mapView(_ mapView: MGLMapView, strokeColorForShapeAnnotation annotation: MGLShape) -> UIColor {

  return .blue
}