Adding a pin annotation to a map view on a long press in swift

问题

I'm trying to make an iPhone app which requires users to be able to long press on a place on a map view to drop a pin there. Does anybody know how this is done?

The behaviour is observable in apple maps when you long press on the screen. It will drop a pin and present an annotation saying "dropped pin"

回答1:

1) Instantiate a UILongPressGestureRecognizer and add it to the MKMapView.

2) When the selector gets called after the user has a long press, call the addAnnotation method in MKMapView with the appropriate title and coordinate.

3) Then make sure you conform to the MKMapViewDelegate and implement viewForAnnotation: which will be called right after you add the annotation and return a MKPinAnnotationView

回答2:

add UILongPressGestureRecognizer to your MapView

var uilgr = UILongPressGestureRecognizer(target: self, action: "addAnnotation:")
uilgr.minimumPressDuration = 2.0

map.add (uilgr)

//IOS 9
map.addGestureRecognizer(uilgr)

Add annotation on Long press detect - func:

func addAnnotation(gestureRecognizer:UIGestureRecognizer){
    if gestureRecognizer.state == UIGestureRecognizerState.Began {
        var touchPoint = gestureRecognizer.locationInView(map)
        var newCoordinates = map.convertPoint(touchPoint, toCoordinateFromView: map)
        let annotation = MKPointAnnotation()
        annotation.coordinate = newCoordinates

        CLGeocoder().reverseGeocodeLocation(CLLocation(latitude: newCoordinates.latitude, longitude: newCoordinates.longitude), completionHandler: {(placemarks, error) -> Void in
            if error != nil {
                println("Reverse geocoder failed with error" + error.localizedDescription)
                return
            }

        if placemarks.count > 0 {
            let pm = placemarks[0] as! CLPlacemark

            // not all places have thoroughfare & subThoroughfare so validate those values
            annotation.title = pm.thoroughfare + ", " + pm.subThoroughfare
            annotation.subtitle = pm.subLocality
            self.map.addAnnotation(annotation)
            println(pm)
        }
        else {
            annotation.title = "Unknown Place"
            self.map.addAnnotation(annotation)
            println("Problem with the data received from geocoder")
        }
        places.append(["name":annotation.title,"latitude":"\(newCoordinates.latitude)","longitude":"\(newCoordinates.longitude)"])
    })
}
}

or you can add annotation without any title:

func action(gestureRecognizer:UIGestureRecognizer){
    var touchPoint = gestureRecognizer.locationInView(map)
    var newCoordinates = map.convertPoint(touchPoint, toCoordinateFromView: map)
    let annotation = MKPointAnnotation()
    annotation.coordinate = newCoordinates
    map.addAnnotation(annotation)
}

回答3:

First declare UIGestureRecognizer in viewDidLoad

let longGesture = UILongPressGestureRecognizer(target: self, action: #selector(addWaypoint(longGesture:)))
mapView.addGestureRecognizer(longGesture)

Second add the function for longPress

@objc func addWaypoint(longGesture: UIGestureRecognizer) {

    let touchPoint = longGesture.location(in: mapView)
    let wayCoords = mapView.convert(touchPoint, toCoordinateFrom: mapView)
    let location = CLLocation(latitude: wayCoords.latitude, longitude: wayCoords.longitude)
    myWaypoints.append(location)

    let wayAnnotation = MKPointAnnotation()
    wayAnnotation.coordinate = wayCoords
    wayAnnotation.title = "waypoint"
    myAnnotations.append(location)
}

I recommend creating the annotations in an array that will serve you later if you want to delete it, like this...

var myAnnotations = [CLLocation]()

If you have different annotations, you can delete only the annotations you want, for that when you add a new annotation add to the array. To delete only one group of annotations just do the following

for dots in myAnnotations{
    mapView.removeAnnotation(dots)
}

To delete all annotations try

mapView.removeAnnotations(mapView.annotations)

Apologies for the translation....

回答4:

Update Swift3

func action(gestureRecognizer:UIGestureRecognizer){
    let touchPoint = gestureRecognizer.location(in: mapView)
    let newCoordinates = mapView.convert(touchPoint, toCoordinateFrom: mapView)
    let annotation = MKPointAnnotation()
    annotation.coordinate = newCoordinates
    mapView.addAnnotation(annotation)
}

来源：https://stackoverflow.com/questions/30858360/adding-a-pin-annotation-to-a-map-view-on-a-long-press-in-swift

标签

ios

swift

annotations

maps

mkmapview