在 Swift 3 中以编程方式创建地图以显示用户位置和注释

Question

我正在尝试复制我在另一个项目中所拥有的内容，在该项目中我只使用代码来使用情节提要。我正在努力使用的视图控制器是地图视图控制器。

我正在尝试创建一个显示用户位置的地图，在启动时围绕该位置缩放到合适的级别，然后允许用户在地图上放置一个图钉，该图钉将在销。

我已经成功地创建了地图并显示了用户位置，但是在地图启动时正在努力设置区域以放大位置。我已经为此苦苦挣扎了几天。

我知道我需要在某处使用 CLlocation2D，但目前不确定在哪里/如何使用它。

我还尝试使用函数设置我的地图，到目前为止的代码如下（这是一个来自不同来源的拙劣工作，试图使其符合我的目标，如果它很混乱，请道歉）

> import UIKit 
> import MapKit 
> import CoreLocation
>
> class MapViewController: UIViewController, MKMapViewDelegate,
> CLLocationManagerDelegate {

>     var mapView: MKMapView!
>     var locationManager = CLLocationManager()
>     
> override func viewDidLoad() {
>         super.viewDidLoad()
>  
>         setupMapView()
> 
>     }
>     
>     override func viewWillAppear(_ animated: Bool) {
>         super.viewWillAppear(animated)
>         
>     }
> 
>     func setupMapView() {
>         let mapView = MKMapView()
> 
>         let leftMargin:CGFloat = 0
>         let topMargin:CGFloat = 0
>         let mapWidth:CGFloat = view.frame.size.width
>         let mapHeight:CGFloat = view.frame.size.height
> 
>         mapView.frame = CGRect(x: leftMargin, y: topMargin, width: mapWidth, height: mapHeight)
> 
>         mapView.mapType = MKMapType.standard
>         mapView.isZoomEnabled = true
>         mapView.isScrollEnabled = true
>         mapView.showsCompass = true
>         mapView.showsScale = true
>         mapView.showsUserLocation = true
>         
>         let noLocation = CLLocationCoordinate2D()
>         let span:MKCoordinateSpan = MKCoordinateSpanMake(0.05, 0.05)
>         let viewLocation = MKCoordinateRegionMake(noLocation, span)
>         
>         
>         mapView.setRegion(viewLocation, animated: true)
>         print(viewLocation)
> 
>         view.addSubview(mapView)
>     }
>  
>     //add function to create circle overlay
> 
> //    override func didReceiveMemoryWarning() { //       
> super.didReceiveMemoryWarning() //        // Dispose of any resources
> that can be recreated. //    }
>     
> 
>     /*
>     // MARK: - Navigation
> 
>     // In a storyboard-based application, you will often want to do a little preparation before navigation
>     override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
>         // Get the new view controller using segue.destinationViewController.
>         // Pass the selected object to the new view controller.
>     }
>     */
> 
> }

对于图钉，我在情节提要中使用了

@IBAction func pinDrop(_ sender: UILongPressGestureRecognizer)

但不确定如何将其转换为程序代码。

任何帮助都会很棒！

Answer 1

像这样添加长按

let longPress = UILongPressGestureRecognizer(target: self, action: #selector(self.addAnnotation(_:)))

self.mapView.addGestureRecognizer(longPress)

//

获取新闻坐标

@objc func addAnnotation(_ gestureRecognizer:UIGestureRecognizer)
{

   if gestureRecognizer.state != UIGestureRecognizerState.began
    {
      return
    }
     let touchPoint = gestureRecognizer.location(in: self.mapView)
     let newCoordinates = self.mapView.convert(touchPoint, toCoordinateFrom: self.mapView)

}

//

 let noLocation =  self.mapView.userLocation.coordinate

 let span:MKCoordinateSpan = MKCoordinateSpanMake(0.05, 0.05)

 let viewLocation = MKCoordinateRegionMake(noLocation, span)

 mapView.setRegion(viewLocation, animated: true)