Question

I added an MKAnnotationView on an MKMapView, when I long press on it, I hope it can be lifted and move to another location.

How to? Special thanks!

Answer 1

For iOS 4.0 or later

From Apple’s Location Awareness Guide > Marking Your Annotation View as Draggable:

To implement minimal support for dragging, you must do the following:

• 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.

Implementing setCoordinate:

#import <MapKit/MapKit.h>
@interface mapAnnotation : NSObject<MKAnnotation> {
    double latitude, longitude; 
}
@end

@implementation mapAnnotation
- (void)setCoordinate:(CLLocationCoordinate2D)coordinate{
    latitude = coordinate.latitude;
    longitude = coordinate.longitude;
}

-(CLLocationCoordinate2D)coordinate {
    CLLocationCoordinate2D coordinate = {latitude,longitude};
    return coordinate;
}
// ...
@end

Creating the annotation view in the view controller:

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{
    static NSString * const identifier = "identifier";
    MKPinAnnotationView *pinView = (MKPinAnnotationView*)[mapView dequeueReusableAnnotationViewWithIdentifier:identifier];
    if (pinView ==nil) {
        pinView = [[MKPinAnnotationView alloc]initWithAnnotation:annotation reuseIdentifier:identifier];
        pinView.animatesDrop = YES;
        pinView.draggable = YES;    
    }
    return pinView;
}

For any iOS version

Track the user touches and move the pin view accordingly. Look at DDAnnotationView at the bottom of this page: http://digdog.tumblr.com/post/252784277/mapkit-annotation-drag-and-drop-with-callout-info

When the user stops dragging convert the view position to map coordinates and change the annotation coordinates. Throw in some animations for the pin.

Here is a working example : https://github.com/digdog/MapKitDragAndDrop Try adding the classes DDAnnotationView and DDAnnotation to your project, and using the MKMapViewDelegate methods below this line.