我在我的大项目中使用 MKMapView。当我加载大量注释(超过 700 个)并在 MapKit 上的这些点之间画线时,我收到 xcode 错误消息“由于内存错误而终止”并且应用程序正在崩溃。你可以在图片上看到:
.
我正在添加这样的行:
如果我的注释少于 700 条,那么它运行良好。我在想它有一些记忆问题。我该如何解决这个问题?任何建议。
// adding annodation
for (int i=0; i<[fetcher.locations count]; i++)//fetcher.locations is NSMutableArray and inside have locationInfoClass objects . locationInfoClass is hold CLLocationCoordinate2D.
{
locationInfoClass * loc=[fetcher2.locations objectAtIndex:i];
CLLocationCoordinate2D coordinate1;
coordinate1.latitude = loc.lat;
coordinate1.longitude = loc.lon;
myAnnotation * ann = [[myAnnotation alloc] initWithCoordinate:annCoordinate title:@"uniqtitle" subtitle:@"uniqsubtitle"];
[mapView addAnnotation:ann];
}
#pragma mark -
#pragma mark -mapview overlay
CLLocationCoordinate2D *coordinates
= malloc(sizeof(CLLocationCoordinate2D) * [mapView.annotations count]);
for (int i=0; i<[mapView.annotations count]; i++) {
myAnnotation * ann=[mapView.annotations objectAtIndex:i];
coordinates[i]=ann.coordinate;
}
self.routeLine = [MKPolyline polylineWithCoordinates:coordinates count:mapView.annotations.count]; // pinlerin sayısı ne kadarsa o kadar çizgi çiziyor.
free(coordinates);
[self.mapView setVisibleMapRect:[self.routeLine boundingMapRect]]; //If you want the route to be visible
dispatch_async(dispatch_get_main_queue(), ^{
[self.mapView addOverlay:self.routeLine];
});
.h 文件有
@property (nonatomic, retain) MKPolyline *routeLine; //your line
@property (nonatomic, retain) MKPolylineView *routeLineView; //overlay view
MKMapView 委托方法。
-(MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id<MKOverlay>)overlay
{
if(overlay == self.routeLine)
{
if(nil == self.routeLineView)
{
self.routeLineView = [[MKPolylineView alloc] initWithPolyline:self.routeLine];
self.routeLineView.fillColor = [UIColor redColor];
self.routeLineView.strokeColor = [UIColor redColor];
self.routeLineView.lineWidth = 3;
}
return self.routeLineView;
}
return nil;
}
/*
- (void)mapView:(MKMapView *)mv didAddAnnotationViews:(NSArray *)views
{
MKAnnotationView *annotationView = [views objectAtIndex:0];
id <MKAnnotation> mp = [annotationView annotation];
MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance([mp coordinate], 1500, 1500);
[mv setRegion:region animated:YES];
}*/
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{
MKAnnotationView *pinView = nil;
if(annotation != mapView.userLocation)
{
static NSString *defaultPinID = @"ftffggf";
pinView = (MKAnnotationView *)[self.mapView dequeueReusableAnnotationViewWithIdentifier:defaultPinID];
if ( pinView == nil )
pinView = [[MKAnnotationView alloc]
initWithAnnotation:annotation reuseIdentifier:defaultPinID];
//pinView.pinColor = MKPinAnnotationColorGreen;
pinView.canShowCallout = YES;
//pinView.animatesDrop = YES;
UIImage * image=[UIImage imageNamed:@"pin.png"];
CGSize size=CGSizeMake(50, 63);//set the width and height
pinView.image = image
}
else {
[self.mapView.userLocation setTitle:@"I am here"];
}
pinView.centerOffset = CGPointMake(0,-23);
return pinView;
}