MKUserLocation点的iOS 10标题箭头

Question

iOS 10中的地图应用程序现在包含一个标题方向箭头MKUserLocation MKAnnotationView.有什么方法可以MKMapView在我自己的应用程序中添加它吗？

编辑:我很乐意手动执行此操作,但我不确定它是否可行？我可以在地图上添加注释并让它跟随用户的位置,包括动画移动吗？

Answer 1

我也遇到了同样的问题(需要一个方向指示器,而不需要地图旋转,类似于Apple Maps应用程序).不幸的是,Apple还没有提供'蓝色图标'标题'API.

我创建了以下@ alku83实现的解决方案.

1. 确保该类符合MKViewDelegate

2. 添加委托方法以将蓝色箭头图标添加到地图位置点

   func mapView(_ mapView: MKMapView, didAdd views: [MKAnnotationView]) {
       if views.last?.annotation is MKUserLocation {
           addHeadingView(toAnnotationView: views.last!)
       }
   }
   

3. 添加方法以创建"蓝色箭头图标".

   func addHeadingView(toAnnotationView annotationView: MKAnnotationView) {
       if headingImageView == nil {
           let image = #YOUR BLUE ARROW ICON#
           headingImageView = UIImageView(image: image)
           headingImageView!.frame = CGRect(x: (annotationView.frame.size.width - image.size.width)/2, y: (annotationView.frame.size.height - image.size.height)/2, width: image.size.width, height: image.size.height)
           annotationView.insertSubview(headingImageView!, at: 0)
           headingImageView!.isHidden = true
        }
   }
   

4. 加入var headingImageView: UIImageView?你的班级.这主要用于变换/旋转蓝色箭头图像.

5. (在不同的类/对象中,具体取决于您的体系结构)创建一个位置管理器实例,该类符合CLLocationManagerDelegate协议

   lazy var locationManager: CLLocationManager = {
       let manager = CLLocationManager()
       // Set up your manager properties here
       manager.delegate = self
       return manager
   }()
   

6. 确保您的位置管理员正在跟踪用户标题数据,locationManager.startUpdatingHeading()并在适当时停止跟踪locationManager.stopUpdatingHeading()

7. 添加var userHeading: CLLocationDirection?哪个将保留方向值

8. 添加委托方法以通知标题值何时更改,并相应地更改userHeading值

   func locationManager(_ manager: CLLocationManager, didUpdateHeading newHeading: CLHeading) {
        if newHeading.headingAccuracy < 0 { return }
   
        let heading = newHeading.trueHeading > 0 ? newHeading.trueHeading : newHeading.magneticHeading
        userHeading = heading
        NotificationCenter.default.post(name: Notification.Name(rawValue: #YOUR KEY#), object: self, userInfo: nil)
       }
   

9. 现在,在符合MKMapViewDelegate的类中,添加方法以"变换"标题图像的方向

      func updateHeadingRotation() {
           if let heading = # YOUR locationManager instance#,
               let headingImageView = headingImageView {
   
               headingImageView.isHidden = false
               let rotation = CGFloat(heading/180 * Double.pi)
               headingImageView.transform = CGAffineTransform(rotationAngle: rotation)
           }
       }
   

Answer 2

是的,您可以手动执行此操作.

基本思想是跟踪用户的位置,CLLocationManager并使用它的数据在地图上放置和旋转注释视图.

这是代码.我忽略了与问题没有直接关系的某些事情(例如,我假设用户已经授权您的应用程序进行位置访问等),所以您可能希望稍微修改一下这段代码

ViewController.swift

import UIKit
import MapKit

class ViewController: UIViewController, CLLocationManagerDelegate, MKMapViewDelegate {
    @IBOutlet var mapView: MKMapView!
    lazy var locationManager: CLLocationManager = {
        let manager = CLLocationManager()
        manager.delegate = self
        return manager
    }()

    var userLocationAnnotation: UserLocationAnnotation!

    override func viewDidLoad() {
        super.viewDidLoad()

        locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation

        locationManager.startUpdatingHeading()
        locationManager.startUpdatingLocation()

        userLocationAnnotation = UserLocationAnnotation(withCoordinate: CLLocationCoordinate2D(), heading: 0.0)

        mapView.addAnnotation(userLocationAnnotation)
    }

    func locationManager(_ manager: CLLocationManager, didUpdateHeading newHeading: CLHeading) {
        userLocationAnnotation.heading = newHeading.trueHeading
    }

    func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        userLocationAnnotation.coordinate = locations.last!.coordinate
    }

    public func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
        if let annotation = annotation as? UserLocationAnnotation {
            let annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: "UserLocationAnnotationView") ?? UserLocationAnnotationView(annotation: annotation, reuseIdentifier: "UserLocationAnnotationView")
            return annotationView
        } else {
            return MKPinAnnotationView(annotation: annotation, reuseIdentifier: nil)
        }
    }

}

在这里,我们正在进行地图视图的基本设置,并开始跟踪用户的位置和标题CLLocationManager.

UserLocationAnnotation.swift

import UIKit
import MapKit

class UserLocationAnnotation: MKPointAnnotation {
    public init(withCoordinate coordinate: CLLocationCoordinate2D, heading: CLLocationDirection) {
        self.heading = heading

        super.init()
        self.coordinate = coordinate
    }

    dynamic public var heading: CLLocationDirection
}

非常简单的MKPointAnnotation子类,能够存储航向.dynamic关键字是关键所在.它允许我们heading用KVO 观察属性的变化.

UserLocationAnnotationView.swift

import UIKit
import MapKit

class UserLocationAnnotationView: MKAnnotationView {

    var arrowImageView: UIImageView!

    private var kvoContext: UInt8 = 13

    override public init(annotation: MKAnnotation?, reuseIdentifier: String?) {
        super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)

        arrowImageView = UIImageView(image: #imageLiteral(resourceName: "Black_Arrow_Up.svg"))
        addSubview(arrowImageView)
        setupObserver()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        arrowImageView = UIImageView(image: #imageLiteral(resourceName: "Black_Arrow_Up.svg"))
        addSubview(arrowImageView)
        setupObserver()
    }

    func setupObserver() {
        (annotation as? UserLocationAnnotation)?.addObserver(self, forKeyPath: "heading", options: [.initial, .new], context: &kvoContext)
    }

    override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
        if context == &kvoContext {
            let userLocationAnnotation = annotation as! UserLocationAnnotation
            UIView.animate(withDuration: 0.2, animations: { [unowned self] in
                self.arrowImageView.transform = CGAffineTransform(rotationAngle: CGFloat(userLocationAnnotation.heading / 180 * M_PI))
            })
        }
    }

    deinit {
        (annotation as? UserLocationAnnotation)?.removeObserver(self, forKeyPath: "heading")
    }
}

MKAnnotationView执行heading属性观察的子类,然后将适当的旋转变换设置为它的子视图(在我的例子中,它只是带箭头的图像.您可以创建更复杂的注释视图并仅旋转它的一部分而不是整个视图. )

UIView.animate是可选的.添加它以使旋转更平滑.CLLocationManager不能每秒观察60次航向值,因此当快速旋转时,动画可能会有点不连贯.UIView.animate电话解决了这个小问题.

妥善处理coordinate值更新已经实施了MKPointAnnotation,MKAnnotationView和MKMapView我们班的,所以我们不必自己动手.

Answer 3

我通过向annotationView添加子视图解决了这个问题MKUserLocation，就像这样

func mapView(mapView: MKMapView, didAddAnnotationViews views: [MKAnnotationView]) {
if annotationView.annotation is MKUserLocation {
    addHeadingViewToAnnotationView(annotationView)
    }
}

func addHeadingViewToAnnotationView(annotationView: MKAnnotationView) {
    if headingImageView == nil {
        if let image = UIImage(named: "icon-location-heading-arrow") {
            let headingImageView = UIImageView()
            headingImageView.image = image
            headingImageView.frame = CGRectMake((annotationView.frame.size.width - image.size.width)/2, (annotationView.frame.size.height - image.size.height)/2, image.size.width, image.size.height)
            self.headingImageView = headingImageView
        }
    }

    headingImageView?.removeFromSuperview()
    if let headingImageView = headingImageView {
        annotationView.insertSubview(headingImageView, atIndex: 0)
    }

    //use CoreLocation to monitor heading here, and rotate headingImageView as required
}