问题描述
我对根据情况更改注释的图钉颜色感兴趣.在一个函数中，我发送了一个数组，该数组确定图钉注释的颜色是什么.到目前为止，我已经设置了一个称为ColorPointAnnotation的子类，该子类将确定pinColor.然后，在switch语句中，为注释设置ColorPointAnnotation.然后在viewForAnnotation中，将新的注释与颜色一起放置.根据我对文档注释的理解，这就是所需要的，但是，销钉颜色在mapView上没有改变.我不确定这可能是什么问题.
I am interested in changing the pin color of an annotation based on a case scenario. In one function, I have an array sent that determines what color the pin annotation is. Thus far, I have set a subclass called ColorPointAnnotation which will determine the pinColor. Then, in the switch statement, I set the ColorPointAnnotation for the annotation. And in the viewForAnnotation, I place the new annotation with the color. From my understanding of annotations from documentation, that is all that is required, however, the pin color is not changing on the mapView. I am not sure what could be the issue.
class ColorPointAnnotation: MKPointAnnotation {
var pinColor: UIColor
init(pinColor: UIColor) {
self.pinColor = pinColor
super.init()
}
}
//here is the function that pulls the array from another view controller
func add(newLocation location_one:[String:Any]) {
let momentaryLat = (location_one["latitude"] as! NSString).doubleValue
let momentaryLong = (location_one["longitude"] as! NSString).doubleValue
var annotation = MKPointAnnotation()
switch String(describing: location_one["eventType"]!) {
case "No":
print("Attending Event")
annotation = ColorPointAnnotation(pinColor: UIColor.red)
case "Yes":
print("Hosting Event")
annotation = ColorPointAnnotation(pinColor: UIColor.green)
default:
print("The pin color is purple")
annotation = ColorPointAnnotation(pinColor: UIColor.purple)
}
annotation.title = location_one["title"] as? String
annotation.coordinate = CLLocationCoordinate2D(latitude: momentaryLat as CLLocationDegrees, longitude: momentaryLong as CLLocationDegrees)
DispatchQueue.main.async {
self.map.addAnnotation(annotation)
}
self.map.centerCoordinate = annotation.coordinate
}
func mapView(_ map: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
// if (annotation is MKUserLocation) {
// return nil
// }
let identifier = "pinAnnotation"
var annotationView = map.dequeueReusableAnnotationView(withIdentifier: identifier) as? MKPinAnnotationView
if annotationView == nil {
annotationView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: identifier)
annotationView?.canShowCallout = true
let colorPointAnnotation = annotation as! ColorPointAnnotation
annotationView?.pinTintColor = colorPointAnnotation.pinColor
}
// else {
// annotationView?.annotation = annotation
//
// }
// map.showAnnotations(map.annotations, animated: true)
return annotationView
}
推荐答案
我认为您的主要问题是您尚未设置map.delegate = self，或者您的视图控制器没有继承自MKMapViewDelegate.
I think your main problem is that you have either have not set map.delegate = self, or your view controller is not inheriting from MKMapViewDelegate.
我也整理了您的代码，下面的代码正常运行.
I have tidied up your code as well, and this code below is functioning properly.
我还修改了您的ColorPointAnnotation类以使其工作更好.
I have also modified your ColorPointAnnotation class to work better.
class ColorPointAnnotation: MKPointAnnotation {
var color: UIColor!
}
视图控制器
import UIKit
import MapKit
class ViewController: UIViewController, MKMapViewDelegate {
@IBOutlet weak var map: MKMapView!
var locations = Array<Dictionary<String,Any>>()
override func viewDidLoad() {
super.viewDidLoad()
// Add some test pins
var attending = Dictionary<String,Any>()
attending["latitude"] = 40.83
attending["longitude"] = -73.93
attending["eventType"] = "No"
attending["title"] = "Testing Attending"
self.locations.append(attending)
var hosting = Dictionary<String,Any>()
hosting["latitude"] = 37.77
hosting["longitude"] = -122.45
hosting["eventType"] = "Yes"
hosting["title"] = "Testing Hosting"
self.locations.append(hosting)
var location = Dictionary<String,Any>()
location["latitude"] = 33.73
location["longitude"] = -84.39
location["title"] = "Testing Default"
self.locations.append(location)
// Add test pins to map
for item in locations {
add(new: item)
}
}
func add(new location: Dictionary<String,Any>) {
guard
let latitude = location["latitude"] as? Double,
let longitude = location["longitude"] as? Double,
let title = location["title"] as? String
else {
print("Incomplete Data")
return
}
let annotation = ColorPointAnnotation()
if let eventType = location["eventType"] as? String {
switch eventType {
case "No":
print("Attending Event")
annotation.color = .red
break
case "Yes":
print("Hosting Event")
annotation.color = .green
break
default :
// I don't need to set this to purple because if
// annotation.color is nil purple will be the default
break
}
}
annotation.title = title
annotation.coordinate = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
self.map.addAnnotation(annotation)
}
func mapView(_ map: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
if let pin = annotation as? ColorPointAnnotation {
let identifier = "pinAnnotation"
if let view = map.dequeueReusableAnnotationView(withIdentifier: identifier) as? MKPinAnnotationView {
view.pinTintColor = pin.color ?? .purple
return view
} else {
let view = MKPinAnnotationView(annotation: annotation, reuseIdentifier: identifier)
view.canShowCallout = true
view.pinTintColor = pin.color ?? .purple
return view
}
}
return nil
}
}
这篇关于Swift 3.0针脚颜色注释在MapView中未更改的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！