ios - 单击注释并更改颜色

Question

我想在用户单击它时更改注释颜色。我的代码就是这样

- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation
{MKPinAnnotationView *annotationView = [[MKPinAnnotationView alloc]initWithAnnotation:view.annotation reuseIdentifier:@"annon1"];
[annotationView setPinColor:MKPinAnnotationColorGreen];
[annotationView setCanShowCallout:YES];
[innerMap selectAnnotation:annotationView.annotation animated:YES];
}

但不适合我。任何人都可以帮助我？？