MKAnnotation - Map Pin callout pops up behind other map pins

Question

My map pins can be quite densely populated so that when a pin is selected the callout pops up but is mostly obscured by all the other map pins - I can bring the Map Pin to the front it there were a delegate for selected map pin ( not tapped callout, selected pin ).

Any suggestions for a work around ?

Answer 1

If you are using custom annotation views you can add an observer for the selected property which would act like a delegate for when the pin is selected.

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation{
    MKAnnotation *annview = ...code to either dequeue or create new object...
    [annview addObserver:self forKeyPath:@"selected" options:NSKeyValueObservingOptionNew context:@"selectedmapannotation"];               
    return annview;
}

then you can monitor the selected state with

- (void)observeValueForKeyPath:(NSString *)keyPath
                  ofObject:(id)object
                    change:(NSDictionary *)change
                   context:(void *)context;

The answer linked by Mugunth Kumar will also give you the desired results it's just that you made mention of delegate like functionality in your question.

EDIT:

Here is an example of the contents of the observeValueForKeyPath:ofObject:change:context: method

NSString *action = (NSString*)context;

if([action isEqualToString:@"selectedmapannotation"]){
    BOOL annotationAppeared = [[change valueForKey:@"new"] boolValue];
    MKAnnotationView *ann = (MKAnnotationView *)object;

    if (annotationAppeared) {
        // do something with the annotation when it is selected
    }
    else {
        // do something with the annotation when it is de-selected
    }
}

Answer 2

UICallout view is the subview of the MKAnnotationView. So, I think if you will bring Map ping to the front, UICAlloutView will be there too.