Showing details when pin tapped (MapKit)

[TelTikky]

I am trying to show the details of a location when the pin is tapped on the map view, I have added the following code:

- (void)mapView:(MKMapView *)map annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control
{
    printf("yes tapped!");
}


- (MKAnnotationView *) mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>) annotation{
    //...
}

Now viewForAnnotation does what it is supposed to do, but annotationView does not get called when a pin is tapped?


This is what's in the .h file:

@interface MapView : UIViewController <MKMapViewDelegate, CLLocationManagerDelegate, UIAlertViewDelegate>
    //...

Anyone has any idea in why it is not working? (will post more code if required).

[apatsufas]

From the documentation of

- (void)mapView:(MKMapView *)map annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control

Accessory views contain custom content and are positioned on either side of the annotation title text. If a view you specify is a descendant of the UIControl class, the map view calls this method as a convenience whenever the user taps your view. You can use this method to respond to taps and perform any actions associated with that control. For example, if your control displayed additional information about the annotation, you could use this method to present a modal panel with that information.

So this method handles taps on the accessoryView of the callout not on the callout it self.

Have you set annotationView.canShowCallout = YES in

- (MKAnnotationView *) mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>) annotation

?

[TelTikky]

Yeah I did, here is my complete viewForAnnotation function.

- (MKAnnotationView *) mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>) annotation{
    MKPinAnnotationView *aView=[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"pin"];
    
    if(spinShouldShow == TRUE)
    {
        [mapSpinner stopAnimating];
        [mapSpinner setHidden:YES];
        spinShouldShow = FALSE;   
    }
    if(annotation.title == @"Current Location" || annotation.title == @"Specified Location")
        aView.pinColor = MKPinAnnotationColorGreen;
    if(annotation.title == @"Start Location" || annotation.title == @"End Location")
    {
        aView.pinColor = MKPinAnnotationColorPurple;
    }
    aView.animatesDrop=TRUE;
    aView.canShowCallout = YES;
    aView.calloutOffset = CGPointMake(-5, 5);
    return aView;
}

Do I have to to init AssessoryView?

Is there anyway I could just tap on the pin and then show the details of the location (possibly in subtitle or in text)? The details should only be updated when the pin is tapped.

[apatsufas]

You don't need the AccessoryView if you don't want it. For the callout View to be shown you must have set at least the title for the annotation.

Put an NSLog in your code to see if you annotation has an title.

Also MKPinAnnotationView is reusable and Apple suggest to reuse it. Also you are leaking the MKPinAnnotationView. It should be autoreleased.

You can try something like this.

static NSString *identifier = @"pin";  

 MKPinAnnotationView *aView = (MKPinAnnotationView *) [self.map dequeueReusableAnnotationViewWithIdentifier:identifier];
        if (aView == nil) {
            aView = [[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier] autorelease];
        } else {
            aView.annotation = annotation;
        }

[TelTikky]

Thanks for the reply.

In my app the pins actually show titles and subtitles. But what I am trying to achieve is when people tap on any particular pin, it will request more info to be displayed. Which means I need to find out when a user tap a pin and which pin is tapped. Then I will use the id stored in that pin to retrieve more info from the web.

[apatsufas]

Then use leftCalloutAccessoryView or rightCalloutAccessoryView to add a View to the pins Callout View. You can handle touches on the AccessoryView with

- (void)mapView:(MKMapView *)map annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control

[KushIP]

Originally Posted by TelTikky

Thanks for the reply.

In my app the pins actually show titles and subtitles. But what I am trying to achieve is when people tap on any particular pin, it will request more info to be displayed. Which means I need to find out when a user tap a pin and which pin is tapped. Then I will use the id stored in that pin to retrieve more info from the web.

Use first method to get the tap on the annotation, derive your annotation class from the view object, do your operation and show the info. on the screen by un hiding a UIView with labels.

Use second method to hide that UIView again.

- (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view{
   
   
}

- (void)mapView:(MKMapView *)mapView didDeselectAnnotationView:(MKAnnotationView *)view{

   
}

[TelTikky]

Originally Posted by KushIP

Use first method to get the tap on the annotation, derive your annotation class from the view object, do your operation and show the info. on the screen by un hiding a UIView with labels.

Use second method to hide that UIView again.

- (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view{
   
   
}

- (void)mapView:(MKMapView *)mapView didDeselectAnnotationView:(MKAnnotationView *)view{

   
}

Thanks for the info. How do I get the MKAnnotation associated with the selected MKAnnotationView in didSelectAnnotationView?

[TelTikky]

Originally Posted by TelTikky

Thanks for the info. How do I get the MKAnnotation associated with the selected MKAnnotationView in didSelectAnnotationView?

Ok this is what you do ...

 - (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view
 {
 
     MapAnnotation *currentAnnotation = view.annotation;
// ...
     

 }

[KushIP]

Originally Posted by TelTikky

Ok this is what you do ...

 - (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view
 {
 
     MapAnnotation *currentAnnotation = view.annotation;
// ...
     

 }

Yes, but be careful if you have multiple type of annotations...

[TelTikky]

Ok, I got the customised MKAnnotationView working, although it looked weird - instead of one view with title, subtitle and the details, I have the normal MKAnnotationView and a separate rectangle for the details.

Has anyone ever worked out how to have one view and put everything inside that view?