removing/adding annotations to mapview cause memory leaks - iphone

Question

I've been trying to get rid of memory leaks in mapview. I am using custom map pin class.
Everything works, but problem is - I need to filter mapview results. when i remove all mapview annotations - and add filtered results - performance tool finds leaks. but in this mapPin class I am using are used autorelease, so they should be released, but they aren't. what am I doing wrong?
MapPin.h
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
#import <MapKit/MKMapView.h>
#import <MapKit/MKAnnotation.h>
#interface MapPin : NSObject<MKAnnotation> {
CLLocationCoordinate2D coordinate;
NSString * picture;
NSInteger tag_number;
}
#property (nonatomic,assign) CLLocationCoordinate2D coordinate;
#property (nonatomic, copy) NSString *title;
#property (nonatomic, copy) NSString *subtitle;
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord;
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title;
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title subtitle:(NSString *) subtitle;
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title subtitle:(NSString *) subtitle image:(NSString *) pic;
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title subtitle:(NSString *) subtitle image:(NSString *) pic num:(NSInteger) number;
- (void) setPic:(NSString *) picture;
- (NSString* ) getPic;
- (void) setNum:(NSInteger) tag_number;
- (NSInteger ) getNum;
#end
MapPin.m
#import "MapPin.h"
#implementation MapPin
#synthesize coordinate = _coordinate;
#synthesize title = _title;
#synthesize subtitle = _subtitle;
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord
{
return [self initWithCoordinate:coord title:#""];
}
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title {
return [self initWithCoordinate:coord title:title subtitle:#""];
}
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title subtitle:(NSString *) subtitle {
return [self initWithCoordinate:coord title:title subtitle:subtitle image:#""];}
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title subtitle:(NSString *) subtitle image:(NSString *) pic{
MapPin * me = [[[MapPin alloc] init] autorelease];
me.coordinate = coord;
me.title = title;
me.subtitle = subtitle;
[me setPic:pic];
return me;
}
- (id) initWithCoordinate:(CLLocationCoordinate2D) coord title:(NSString *) title subtitle:(NSString *) subtitle image:(NSString *) pic num:(NSInteger) number{
MapPin * me = [[[MapPin alloc] init] autorelease];
me.coordinate = coord;
me.title = title;
me.subtitle = subtitle;
[me setPic:pic];
[me setNum:number];
return me;
}
- (void) setPic:(NSString*) pic {
picture = pic;
}
- (NSString * ) getPic{
return picture;
}
- (void) setNum:(NSInteger) number {
tag_number = number;
}
- (NSInteger ) getNum{
return tag_number;
}
#end

Answer 1

I have been using cutom map pin created by Mayur Birari, which i tweaked a little bit, to support custom map pin images and id's.
CustomMapPin.h
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
#interface CustomMapPin : NSObject<MKAnnotation> {
CLLocationCoordinate2D coordinate;
NSString* title;
NSString* subtitle;
NSString* pic;
NSInteger tag_number;
}
#property (nonatomic, assign) CLLocationCoordinate2D coordinate;
#property (nonatomic, copy) NSString* title;
#property (nonatomic, copy) NSString* subtitle;
#property (nonatomic, copy) NSString* pic;
#property (nonatomic) NSInteger tag_number;
#end
CustomMapPin.m
#import "CustomMapPin.h"
#implementation CustomMapPin
#synthesize title;
#synthesize subtitle;
#synthesize coordinate;
#synthesize pic;
#synthesize tag_number;
- (void)dealloc
{
self.title = nil;
self.pic = nil;
self.subtitle = nil;
[super dealloc];
}
#end
and using it in class like this:
CLLocationCoordinate2D pinlocation;
in a loop I set up required values and create a map pin:
pinlocation.latitude = ...;
pinlocation.longitude = ...;
NSInteger pinID = ....;
CustomMapPin* customMapPin=[[CustomMapPin alloc] init];
customMapPin.coordinate=(CLLocationCoordinate2D
{pinlocation.latitude,pinlocation.longitude};
customMapPin.title=#"title";
customMapPin.subtitle=#"subtitle";
customMapPin.pic = #"customImageName";
customMapPin.tag_number = pinId;
[mapView addAnnotation:customMapPin];
Setting up custom image:
- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation
{
if ([annotation isKindOfClass: [CustomMapPin class]])
{
CustomMapPin * a = annotation;
[annView setImage:[UIImage imageNamed:a.pic]];
}
}
Getting pin id on callout:
- (void)mapView:(MKMapView *)mp annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control
{
CustomMapPin * v = (CustomMapPin *) view.annotation;
int tagNumber = v.tag_number;
....
}
and finally - in my project It was required to have filter buttons - so I needed to remove all pins, and add required. By default calling mapview to remove all annotations created memory leaks. So when I need to clear mapview from annotations, I call this function:
- (void)removeAnnotations
{
NSMutableArray *toRemove = [NSMutableArray arrayWithCapacity:[mapView.annotations count]];
for (id annotation in mapView.annotations)
{
if (annotation != mapView.userLocation)
{
[toRemove addObject:annotation];
}
}
[mapView removeAnnotations:toRemove];
for(int i = 0; i < [toRemove count]; i++)
{
CustomMapPin * a = [toRemove objectAtIndex:i];
[a release];
a = nil;
}
}
Hope this helps
Happy coding! :)

Answer 2

You were just missing dealloc implementation!
for example:
- (void)dealloc
{
[self.title release];
self.title = nil;
self.subtitle release];
self.subtitle = nil;
[super dealloc];
}