6.5. Displaying Pins with Different Colors on a Map View
Problem
The default color for pins dropped on a map view is red. You want to be able to display pins in different colors in addition to the default color.
Solution
Return instances of MKPinAnnotationView
to your map view through
the mapView:viewForAnnotation:
delegate
method.
Every annotation that is added to an instance of MKMapView
has a
corresponding view that gets displayed on the map view. These views
are called annotation views. An annotation view is an object of type
MKAnnotationView
, which is a
subclass of UIView
. If the delegate
object of a map view implements the mapView:viewForAnnotation:
delegate method,
the delegate object will have to return instances of the MKAnnotationView
class
to represent (and optionally, customize) the annotation views to be
displayed on a map view.
Discussion
To set up our program so we can customize the color (choosing
from the default SDK pin colors) of the annotation view that gets
dropped on a map view to represent the annotation, we must return an
instance of the MKPinAnnotationView
class instead of an instance of MKAnnotationView
in the mapView:viewForAnnotation:
delegate method.
Bear in mind that the MKPinAnnotationView
class is a subclass of
the MKAnnotationView
class.
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation{ MKAnnotationView *result = nil; if ([annotation isKindOfClass:[MyAnnotation class]] == NO){ return result; } if ([mapView ...
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