How to clear all map after switching storyboards?

Question

I have 2 storyboards. I need to switch between them. The first storyboard has a map view controller. When I switch to the second storyboard, I change rootViewController, as below

let appDelegate = UIApplication.shared.delegate! as! AppDelegate
let storyboard = UIStoryboard(name: "LoginController", bundle: nil)
let viewController = storyboard.instantiateViewController(withIdentifier: "LoginController")
appDelegate.window?.rootViewController = viewController
appDelegate.window?.makeKeyAndVisible()

But when I open the first storyboard I see all annotations as earlier. How can I remove cache from map?

let annotations = mapView.annotations; mapView.removeAnnotations(annotations) — El Tomato, Mar 29 '19 at 13:22
Possible duplicate of [How to delete all Annotations on a MKMapView](https://stackoverflow.com/questions/3027392/how-to-delete-all-annotations-on-a-mkmapview) — AamirR, Mar 29 '19 at 13:48

score 0 · Answer 1 · answered Mar 29 '19 at 13:10

its because the mapviewController is still exist with the map annotations just remove all annotations before switching below is the required code:-

for (int i =0; i < [mapView.annotations count]; i++) { 
    if ([[mapView.annotations objectAtIndex:i] isKindOfClass:[MyAnnotationClass class]]) {                      
         [mapView removeAnnotation:[mapView.annotations objectAtIndex:i]]; 
       } 
    }

score 0 · Answer 2 · edited Mar 29 '19 at 14:01

0

Only to remove the annotations during the transition to second storyboard, you could try

override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)
    self.mapView.removeAnnotations(mapView.annotations)
}

edited Mar 29 '19 at 14:01

AamirR

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answered Mar 29 '19 at 13:32

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Use `mapView.removeAnnotations(mapView.annotations)`, if statement will cause compile error, `mapView.annotations` never returns `nil` – AamirR Mar 29 '19 at 13:43
@AamirR Updated – iOS Mar 29 '19 at 13:54

How to clear all map after switching storyboards?

2 Answers2