How to zoom out of an MKMapView without using didAddAnnotationViews?

Question

I am trying to find a way to do a zoom in and out via a button. If I put code within the method didAddAnnotationViews, it will set the initial zoom perfectly. I tried to get the zoom to change with the code below, but it keeps on crashing saying:

Unrecognized Selector sent to Instance

How can I run this in an IBAction?

-(IBAction)ZoomIn:(MKCoordinateSpan)coordinateSpanWithMapView:(MKMapView *)mv centerCoordinate:(CLLocationCoordinate2D)location
{
   MKCoordinateRegion region;
   MKCoordinateSpan span; 
   span.latitudeDelta=0.05;
   span.longitudeDelta=0.05;
   location = mv.userLocation.coordinate;
   location = mv.userLocation.location.coordinate;
   region.span=span;
   region.center=location;
   [mv setRegion:region animated:TRUE];
   [mv regionThatFits:region]; 
};

can you please post full error message? Why are you taking "location" as a input when you are assigning it to userlocation coordinate? — chatur, Jan 16 '12 at 11:12
Are you calling this method programmatically or is it hooked up to a button action in IB? If IB then this method doesn't have the correct signature for a button action method. If programmatically, show how you are calling it. — , Jan 16 '12 at 14:20
[MapView ZoomIn]: unrecognized selector sent to instance 0x8768200. I removed the passing in of location and it still breaks — logixologist, Jan 16 '12 at 17:31
For a control action, the first parameter will be the control sending the message. If the action is linked to a button, the first parameter will be the UIButton regardless of what parameter type or name you give in the method. See [Cocoa Target-Action](http://developer.apple.com/library/ios/#documentation/general/conceptual/Devpedia-CocoaApp/TargetAction.html). — , Jan 16 '12 at 18:12

score 0 · Answer 1 · edited Jan 08 '16 at 10:59

0

-(void)zoomOut:btnMinus
{
  MKCoordinateSpan span = mapView.region.span;
  span.latitudeDelta = span.latitudeDelta * 2;
  span.longitudeDelta = span.longitudeDelta * 2;
  region.span=span;
  [mapView setRegion:region animated:YES];
  for(int j=2;j<count;j++)
  { places[j]=1;}
  [self filterAnnotations];  
}

edited Jan 08 '16 at 10:59

Nagarjun

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answered Jan 31 '14 at 07:58

Ankit Goyal

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score 0 · Answer 2 · answered Jan 17 '12 at 04:33

My issue was that I was trying to pass in the MapView in the IBAction line which I couldnt do. It did not know what to do with it. I referenced my MapView in the code instead of trying to pass it in the method...

CLLocationCoordinate2D location;
MKCoordinateRegion region;
MKCoordinateSpan span; 
span.latitudeDelta=1.00;
span.longitudeDelta=1.00;
location = self.myMap.userLocation.coordinate;
location = self.myMap.userLocation.location.coordinate;
region.span=span;
region.center=location;
[self.LightUpMap setRegion:region animated:TRUE];
[self.LightUpMap regionThatFits:region];

You can put this is any IBAction method now and it will zoom in to the map.

How to zoom out of an MKMapView without using didAddAnnotationViews?

2 Answers2