CODEWITHSUNDEEP
iosswiftmapkitmkannotation
SHINTO JOSEPH
SHINTO JOSEPH

Reputation: 387

iOS Mapkit Annotation is not getting draggable

I am new to iOS development and I need to implement a draggable annotation in iOS maps. my code is given below.whater ever I do I can't get a draggable annotation can anyone help with the annotations after that I need to get address of the location where the pin is pointing

RegistrationViewController.swift

class RegistrationViewController: UIViewController,UIPickerViewDelegate,UIPickerViewDataSource,MKMapViewDelegate{
    @IBOutlet weak var mapView: MKMapView!

    override func viewDidLoad() {
        super.viewDidLoad()
        var centerLocation = CLLocationCoordinate2DMake(12.964370125970357, 77.59643554937497)
        var mapspan = MKCoordinateSpanMake(0.01, 0.01)
        var mapregion = MKCoordinateRegionMake(centerLocation, mapspan)
        self.mapView.setRegion(mapregion, animated: true)

        let pin = pinAnnotation(title:"hello",subtitle:"how are you",coordinate:centerLocation)
        mapView.addAnnotation(pin)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }

    func mapView(mapView: MKMapView!, viewForAnnotation annotation: MKAnnotation!) -> MKAnnotationView! {
        if annotation is MKPointAnnotation {
            let pinAnnotationView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "myPin")
            pinAnnotationView.pinColor = .purple
            pinAnnotationView.isDraggable = true
            pinAnnotationView.canShowCallout = true
            pinAnnotationView.animatesDrop = true

            return pinAnnotationView
        }

        return nil
    }

    func mapView(_ mapView: MKMapView, annotationView view: MKAnnotationView, didChange newState: MKAnnotationViewDragState, fromOldState oldState: MKAnnotationViewDragState) {
        switch newState {
        case .starting:
            view.dragState = .dragging
        case .ending, .canceling:
            view.dragState = .none
        default: break
        }
    }

pinAnnotation.swift

import MapKit

class pinAnnotation:NSObject,MKAnnotation {
    var title:String?
    var subtitle: String?
    var coordinate: CLLocationCoordinate2D
    init(title:String,subtitle:String,coordinate:CLLocationCoordinate2D) {
        self.title = title
        self.subtitle = subtitle
        self.coordinate = coordinate
    }
}

Upvotes: 4

Views: 2002

Answers (2)

Dharmesh Kheni
Dharmesh Kheni

Reputation: 71852

In your case annotation is not an MKPointAnnotation type. Thats why its not entering into if annotation is MKPointAnnotation { condition.

It should be like:

func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {

    if annotation is pinAnnotation {

        let pinAnnotationView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "myPin")
        pinAnnotationView.pinTintColor = .purple
        pinAnnotationView.isDraggable = true
        pinAnnotationView.canShowCallout = true
        pinAnnotationView.animatesDrop = true

        return pinAnnotationView
    }

    return nil
}

Because annotation is pinAnnotation type.

And I can not see mapView.delegate = self in your code. But if you assign it via storyboard thats fine otherwise add it in viewDidLoad method.

And your complete code will be:

import UIKit
import MapKit

class ViewController: UIViewController,MKMapViewDelegate{
    @IBOutlet weak var mapView: MKMapView!


    override func viewDidLoad() {
        super.viewDidLoad()
        mapView.delegate  = self
        let centerLocation = CLLocationCoordinate2D(latitude: 12.964370125970357, longitude: 77.59643554937497)
        let mapspan = MKCoordinateSpanMake(0.01, 0.01)
        let mapregion = MKCoordinateRegionMake(centerLocation, mapspan)
        self.mapView.setRegion(mapregion, animated: true)

        let pin = pinAnnotation(title:"hello",subtitle:"how are you",coordinate:centerLocation)
        mapView.addAnnotation(pin)

    }


    func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {

        if annotation is pinAnnotation {

            let pinAnnotationView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: "myPin")
            pinAnnotationView.pinTintColor = .purple
            pinAnnotationView.isDraggable = true
            pinAnnotationView.canShowCallout = true
            pinAnnotationView.animatesDrop = true

            return pinAnnotationView
        }

        return nil
    }

    func mapView(_ mapView: MKMapView, annotationView view: MKAnnotationView, didChange newState: MKAnnotationViewDragState, fromOldState oldState: MKAnnotationViewDragState) {
        switch newState {
        case .starting:
            view.dragState = .dragging
        case .ending, .canceling:
            view.dragState = .none
        default: break
        }
    }
}

EDIT

You can get new location with view.annotation?.coordinate

check below code:

func mapView(_ mapView: MKMapView, annotationView view: MKAnnotationView, didChange newState: MKAnnotationViewDragState, fromOldState oldState: MKAnnotationViewDragState) {
    switch newState {
    case .starting:
        view.dragState = .dragging
    case .ending, .canceling:
        //New cordinates
        print(view.annotation?.coordinate)
        view.dragState = .none
    default: break
    }
}

Upvotes: 5

pesch
pesch

Reputation: 1996

You have the first step done by setting the isDraggable property to true. Now you only need to handle when the user stops dragging and drops the annotation, see: how to manage drag and drop for MKAnnotationView on IOS

Besides, your pinAnnotation should have a settable coordinates.

From Apple documentation:

Marking Your Annotation View as Draggable Annotation views provide built-in dragging support, which makes it very easy to drag annotations around the map and to ensure that the annotation data is updated accordingly. To implement minimal support for dragging:

In your annotation objects, implement the setCoordinate: method to allow the map view to update the annotation’s coordinate point. When creating your annotation view, set its draggable property to YES. When the user touches and holds a draggable annotation view, the map view begins a drag operation for it. As the drag operation progresses, the map view calls the mapView:annotationView:didChangeDragState:fromOldState: method of its delegate to notify it of changes to the drag state of your view. You can use this method to affect or respond to the drag operation.

To animate your view during a drag operation, implement a custom dragState method in your annotation view. As the map view processes drag-related touch events, it updates the dragState property of the affected annotation view. Implementing a custom dragState method gives you a chance to intercept these changes and perform additional actions, such as animating the appearance of your view. For example, the MKPinAnnotationView class raises the pin off the map when a drag operation starts and drops the pin back down on the map when it ends.

You are missing the mapView:annotationView:didChangeDragState:fromOldState: method

Upvotes: 2

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