快速添加不同的图像进行注释

Question

我设法在Swift中为注释图钉获得了一个自定义图标，但现在我仍然对2个不同的注释使用不同的图像。现在，一个按钮会向地图添加注释。应该有另一个按钮，该按钮也添加了注释，但带有另一个图标。

是否有办法为此使用复用标识？

class ViewController: UIViewController, MKMapViewDelegate {

@IBOutlet weak var Map: MKMapView!

@IBAction func btpressed(sender: AnyObject) {

    var lat:CLLocationDegrees = 40.748708
    var long:CLLocationDegrees = -73.985643
    var latDelta:CLLocationDegrees = 0.01
    var longDelta:CLLocationDegrees = 0.01

    var span:MKCoordinateSpan = MKCoordinateSpanMake(latDelta, longDelta)
    var location:CLLocationCoordinate2D = CLLocationCoordinate2DMake(lat, long)
    var region:MKCoordinateRegion = MKCoordinateRegionMake(location, span)

    Map.setRegion(region, animated: true)


    var information = MKPointAnnotation()
    information.coordinate = location
    information.title = "Test Title!"
    information.subtitle = "Subtitle"

    Map.addAnnotation(information)
}

func mapView(mapView: MKMapView!, viewForAnnotation annotation: MKAnnotation!) -> MKAnnotationView! {
    if !(annotation is MKPointAnnotation) {
        return nil
    }

    let reuseId = "test"

    var anView = mapView.dequeueReusableAnnotationViewWithIdentifier(reuseId)
    if anView == nil {
        anView = MKAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
        anView.image = UIImage(named:"1.png")
        anView.canShowCallout = true
    }
    else {
        anView.annotation = annotation
    }

    return anView
}

Answer 1

在viewForAnnotation委托方法中，根据要调用的方法image设置annotation。

请确保执行此操作[，使视图出列或创建视图（不仅在if anView == nil部分中）。否则，使用出队视图的注释将显示以前使用该视图的注释的图像。

使用基本的MKPointAnnotation，区分注释的一种粗略方法是通过它们的title，但这不是很灵活。

一种更好的方法是使用实​​现MKAnnotation协议的自定义注释类（一种简单的方法是将MKPointAnnotation子类化，并添加帮助实现自定义逻辑所需的任何属性。

在自定义类中，添加一个属性，例如imageName，可用于基于注释自定义图像。

此示例子类为MKPointAnnotation：

class CustomPointAnnotation: MKPointAnnotation {
    var imageName: String!
}

创建类型为CustomPointAnnotation的注释并设置其imageName：
var info1 = CustomPointAnnotation()
info1.coordinate = CLLocationCoordinate2DMake(42, -84)
info1.title = "Info1"
info1.subtitle = "Subtitle"
info1.imageName = "1.png"

var info2 = CustomPointAnnotation()
info2.coordinate = CLLocationCoordinate2DMake(32, -95)
info2.title = "Info2"
info2.subtitle = "Subtitle"
info2.imageName = "2.png"

在viewForAnnotation中，使用imageName属性设置视图的image：
func mapView(mapView: MKMapView!, viewForAnnotation annotation: MKAnnotation!) -> MKAnnotationView! {
    if !(annotation is CustomPointAnnotation) {
        return nil
    }

    let reuseId = "test"

    var anView = mapView.dequeueReusableAnnotationViewWithIdentifier(reuseId)
    if anView == nil {
        anView = MKAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
        anView.canShowCallout = true
    }
    else {
        anView.annotation = annotation
    }

    //Set annotation-specific properties **AFTER**
    //the view is dequeued or created...

    let cpa = annotation as CustomPointAnnotation
    anView.image = UIImage(named:cpa.imageName)

    return anView
}

Answer 2

借助Anna和Fabian Boulegue的iOS Swift代码：

import UIKit
import MapKit

class ViewController: UIViewController, MKMapViewDelegate {

    @IBOutlet weak var mapView: MKMapView!

    override func viewDidLoad() {
        super.viewDidLoad()

        self.mapView.delegate = self

        var info1 = CustomPointAnnotation()
        info1.coordinate = CLLocationCoordinate2DMake(26.889281, 75.836042)
        info1.title = "Info1"
        info1.subtitle = "Subtitle"
        info1.imageName = "flag.png"

        var info2 = CustomPointAnnotation()
        info2.coordinate = CLLocationCoordinate2DMake(26.862280, 75.815098)
        info2.title = "Info2"
        info2.subtitle = "Subtitle"
        info2.imageName = "flag.png"

        mapView.addAnnotation(info1)
        mapView.addAnnotation(info2)
    }

    func mapView(mapView: MKMapView!, viewForAnnotation annotation: MKAnnotation!) -> MKAnnotationView! {

        println("delegate called")

        if !(annotation is CustomPointAnnotation) {
            return nil
        }

        let reuseId = "test"

        var anView = mapView.dequeueReusableAnnotationViewWithIdentifier(reuseId)
        if anView == nil {
            anView = MKAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
            anView.canShowCallout = true
        }
        else {
            anView.annotation = annotation
        }

        //Set annotation-specific properties **AFTER**
        //the view is dequeued or created...

        let cpa = annotation as CustomPointAnnotation
        anView.image = UIImage(named:cpa.imageName)

        return anView
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

class CustomPointAnnotation: MKPointAnnotation {
    var imageName: String!
}

Answer 3

SWIFT 5

let pointAnnotation = MKPointAnnotation()

override func viewDidLoad()
{
   mapVw.delegate = self
 pointAnnotation.coordinate = CLLocationCoordinate2D(latitude: yourLatitude, longitude:yourLongitude)
 mapVw.addAnnotation(pointAnnotation)

}

// MARK:- MapView Delegate


func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView?
{
    if annotation is MKUserLocation
    {
        return nil;
    }else{
        let pinIdent = "Pin";
        var pinView: MKAnnotationView?
        if let dequeuedView = mapView.dequeueReusableAnnotationView(withIdentifier: pinIdent)
        {
            dequeuedView.annotation = annotation;
            pinView = dequeuedView;
        }
        else
        {
            pinView = MKAnnotationView(annotation: annotation, reuseIdentifier: pinIdent);
            pinView?.image = UIImage(named: "yourImage")

        }


        return pinView;
    }
}