Swift 通过分段控制更改地图类型(混合、卫星)
我试图改变地图类型使用分段控制按钮,我希望它改变地图类型与3个选项:标准,卫星和混合。到目前为止,我有这段代码,但一旦选择了不同的贴图类型,就不会发生任何事情:Swift 通过分段控制更改地图类型(混合、卫星),swift,mkmapview,hybrid,Swift,Mkmapview,Hybrid,我试图改变地图类型使用分段控制按钮,我希望它改变地图类型与3个选项:标准,卫星和混合。到目前为止,我有这段代码,但一旦选择了不同的贴图类型,就不会发生任何事情: @IBAction func segmentedControlAction(sender: UISegmentedControl!) { if sender.selectedSegmentIndex == 0{ mapView.mapType = MKMapType.Standard } el
@IBAction func segmentedControlAction(sender: UISegmentedControl!) {
if sender.selectedSegmentIndex == 0{
mapView.mapType = MKMapType.Standard
}
else if sender.selectedSegmentIndex == 1{
mapView.mapType = MKMapType.Satellite
}
else if sender.selectedSegmentIndex == 3{
mapView.mapType = MKMapType.Hybrid
}
}
我是Swift和Xcode新手,因此非常感谢您的帮助:)
谢谢首先,确保在分段控件选择更改时调用您的方法。很容易忘记连接出口方法。一旦您验证了这一点,请记住地图数据是异步加载的,因此您可能不会在选择其他模式后立即看到它的更改。但是,对于您发布的代码,您将永远看不到
.Hybrid
类型,因为三段控件中的selectedSegmentIndex
永远不会是3
实现此方法的更简洁的方法是:
@IBAction func segmentedControlAction(sender: UISegmentedControl!) {
switch (sender.selectedSegmentIndex) {
case 0:
mapView.mapType = .Standard
case 1:
mapView.mapType = .Satellite
default:
mapView.mapType = .Hybrid
}
}
请注意,Swift不需要在每个案例的结尾处使用break
语句
编辑:Swift 4.1
@IBAction func mapTypeSegmentSelected(_ sender: UISegmentedControl) {
switch sender.selectedSegmentIndex {
case 0:
mapView.mapType = .standard
case 1:
mapView.mapType = .satellite
default:
mapView.mapType = .hybrid
}
}
很可能。。mapView为nil或该方法未被调用。通常,最好解释一个解决方案,而不是仅仅发布几行匿名代码。您可以阅读,也可以是no.normal,它是:mapView.mapType=.standard
import CoreLocation
import MapKit
class ViewController: UIViewController,CLLocationManagerDelegate,MKMapViewDelegate {
@IBOutlet weak var my_map: MKMapView!
var my_location = CLLocationManager()
enum maptype:NSInteger
{
case standardmap = 0
case satellitemap = 1
case hybridmap = 2
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
self.my_map.showsUserLocation = true
self.my_map.delegate = self
self.my_location = CLLocationManager.init()
self.my_location.delegate = self
self.my_location.requestWhenInUseAuthorization()
self.my_location.stopUpdatingLocation()
let location = CLLocationCoordinate2DMake(11.004556, 76.961632)
let span = MKCoordinateSpanMake(0.1, 0.1)
let region = MKCoordinateRegionMake(location, span)
my_map.setRegion(region, animated: true)
let annotation = MKPointAnnotation()
annotation.coordinate = location
annotation.title = "coimbatore"
annotation.subtitle = "manchester city"
my_map.addAnnotation(annotation)
}
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView?
{
/*let annotationview = MKAnnotationView(annotation: annotation, reuseIdentifier: "pin")
annotationview.image = UIImage(named:"nature.jpeg")
//let transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
//annotationview.transform = transform
return annotationview*/
let annotationReuseId = "Place"
var anView = mapView.dequeueReusableAnnotationView(withIdentifier: annotationReuseId)
if anView == nil {
anView = MKAnnotationView(annotation: annotation, reuseIdentifier: annotationReuseId)
} else {
anView?.annotation = annotation
}
anView?.image = UIImage(named: "annotation")
let transform = CGAffineTransform(scaleX: 0.1, y: 0.1)
anView?.transform = transform
anView?.backgroundColor = UIColor.clear
anView?.canShowCallout = false
return anView
}
@IBAction func maptypes(_ sender: Any)
{
switch(sender as AnyObject).selectedSegmentIndex
{
case maptype.standardmap.rawValue:
my_map.mapType = .standard
case maptype.satellitemap.rawValue:
my_map.mapType = .satellite
case maptype.hybridmap.rawValue:
my_map.mapType = .hybrid
default:
break
}
}