问题
I managed to get a custom icon for a annotation pin in Swift, but now I am still stuck using 2 different images for different annotations. Right now a button adds a annotation to the map. There should be another button that also adds a annotation but with another icon.
Is there a way to use the reuseId for this?
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
}
回答1:
In the viewForAnnotation
delegate method, set the image
based on which annotation
the method is being called for.
Be sure to do this after the view is dequeued or created (and not only in the if anView == nil
part). Otherwise, annotations that use a dequeued view will show the image of the annotation that used the view previously.
With the basic MKPointAnnotation
, one crude way to tell annotations apart is by their title
but that's not very flexible.
A better approach is to use a custom annotation class that implements the MKAnnotation
protocol (an easy way to do that is to subclass MKPointAnnotation
) and add whatever properties are needed to help implement the custom logic.
In the custom class, add a property, say imageName
, which you can use to customize the image based on the annotation.
This example subclasses MKPointAnnotation
:
class CustomPointAnnotation: MKPointAnnotation {
var imageName: String!
}
Create annotations of type CustomPointAnnotation
and set their 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"
In viewForAnnotation
, use the imageName
property to set the view's 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
}
回答2:
iOS Swift Code With Help of Anna and Fabian Boulegue:
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!
}
来源:https://stackoverflow.com/questions/25631410/swift-different-images-for-annotation