I had to get the coordinate of a point where the user touch on a MKMapView. I\'m not working with the Interface Builder. Can you give me one example?
Thanks to Anna for providing such a great answer! Here is a Swift version if anybody is interested (the answer has been updated to Swift 4.1 syntax).
Creating UILongPressGestureRecognizer:
let longPressRecogniser = UILongPressGestureRecognizer(target: self, action: #selector(MapViewController.handleLongPress(_:)))
longPressRecogniser.minimumPressDuration = 1.0
mapView.addGestureRecognizer(longPressRecogniser)
Handling the gesture:
@objc func handleLongPress(_ gestureRecognizer : UIGestureRecognizer){
if gestureRecognizer.state != .began { return }
let touchPoint = gestureRecognizer.location(in: mapView)
let touchMapCoordinate = mapView.convert(touchPoint, toCoordinateFrom: mapView)
let album = Album(coordinate: touchMapCoordinate, context: sharedContext)
mapView.addAnnotation(album)
}
You can use a UILongPressGestureRecognizer for this. Wherever you create or initialize the mapview, first attach the recognizer to it:
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc]
initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 2.0; //user needs to press for 2 seconds
[self.mapView addGestureRecognizer:lpgr];
[lpgr release];
Then in the gesture handler:
- (void)handleLongPress:(UIGestureRecognizer *)gestureRecognizer
{
if (gestureRecognizer.state != UIGestureRecognizerStateBegan)
return;
CGPoint touchPoint = [gestureRecognizer locationInView:self.mapView];
CLLocationCoordinate2D touchMapCoordinate =
[self.mapView convertPoint:touchPoint toCoordinateFromView:self.mapView];
YourMKAnnotationClass *annot = [[YourMKAnnotationClass alloc] init];
annot.coordinate = touchMapCoordinate;
[self.mapView addAnnotation:annot];
[annot release];
}
YourMKAnnotationClass is a class you define that conforms to the MKAnnotation protocol. If your app will only be running on iOS 4.0 or later, you can use the pre-defined MKPointAnnotation class instead.
For examples on creating your own MKAnnotation class, see the sample app MapCallouts.