Question

我想使用我自己的Image vor我在地图中的注释。但我只得到默认的针脚。

这是我的mapView：ForAnnotation：Method

  MKAnnotationView* annotationView = nil;
if ([annotation isKindOfClass:[PlayerLocation class]]){
   PlayerLocation* annotation2 = (PlayerLocation*)annotation;
    static NSString *identifier = @"MyView";   
    MKAnnotationView *annotationView = (MKAnnotationView *) [mapV dequeueReusableAnnotationViewWithIdentifier:identifier];
    if (annotationView == nil) {
        annotationView = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier];
    } else {
        annotationView.annotation = annotation;
    }


    NSString* path = [[NSBundle mainBundle] pathForResource:@"MKAnnotation" ofType:@"png"];
    UIImage* im = [[UIImage alloc] initWithContentsOfFile:path];

    annotationView.image= im;

    annotationView.enabled = YES;
    annotationView.canShowCallout = YES;
    //delete the flagged Locations
    [self performSelectorOnMainThread:@selector(deletePin:) withObject:annotation2.name waitUntilDone:NO];
}
return annotationView;

我无法找到它的错误。图像被发现不是nil。委托被设置。协议在那里，方法被调用。

以下是添加注释所涉及的全部代码。 “drawGamers”是入口点，由网络处理类调用。

-(void)drawGamers:(NSMutableArray*)locations{

    for(PlayerLocation* loc in locations ){
        [ self replacePin:loc.name withLocation:loc.coordinate];
    }

}

-(void)replacePin:(NSString *)gamerName  withLocation:(CLLocationCoordinate2D)location {
    // flag Location for deletion later
    for (PlayerLocation* annotation in _mapView.annotations){
        if ([annotation.name isEqualToString:gamerName])
            annotation.decomission = YES;
    }
    //add new Location
    PlayerLocation *pLoc = nil;
    pLoc = [[PlayerLocation alloc] initWithName:gamerName address:nil coordinate:location];
    [_mapView addAnnotation:pLoc];
}



- (MKAnnotationView *)mapView:(MKMapView *)mapV viewForAnnotation:(id <MKAnnotation>)annotation{
    MKAnnotationView* annotationView = nil;
    if ([annotation isKindOfClass:[PlayerLocation class]]){
       PlayerLocation* annotation2 = (PlayerLocation*)annotation;
        static NSString *identifier = @"MyView";   
        MKAnnotationView *annotationView = (MKAnnotationView *) [mapV dequeueReusableAnnotationViewWithIdentifier:identifier];
        if (annotationView == nil) {
            annotationView = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier];
        } else {
            annotationView.annotation = annotation;
        }


        NSString* path = [[NSBundle mainBundle] pathForResource:@"MKAnnotation" ofType:@"png"];
        UIImage* im = [[UIImage alloc] initWithContentsOfFile:path];

        annotationView.image= im;

        annotationView.enabled = YES;
        annotationView.canShowCallout = YES;
        //delete the flagged Locations
        [self performSelectorOnMainThread:@selector(deletePin:) withObject:annotation2.name waitUntilDone:NO];
    }
    return annotationView;
}

-(void)deletePin:(NSString *)stationCode{
    for (PlayerLocation *annotation in _mapView.annotations) {
        if ([annotation.name isEqualToString:stationCode]){  
            if (annotation.decomission==YES)
            [_mapView removeAnnotation:annotation];
        }
    }
}

我无法找到问题所在。

Answer 1

在viewForAnnotation中，annotationView变量被声明两次。

首先在顶部，然后再在if内。因此if内的设置对外部声明的变量没有影响。

return是在外部变量上完成的，该变量保持nil。

不要在if内重新声明变量 - 只需设置它。

Answer 2

- (MKAnnotationView *) mapView:(MKMapView *)mapingView viewForAnnotation:(id <MKAnnotation>) annotation {

     MKAnnotationView* annotationView = nil;
    if ([annotation isKindOfClass:[PlayerLocation class]])
    {
         PlayerLocation* annotation2 = (PlayerLocation*)annotation;
         static NSString *identifier = @"MyView";   

         annotationView = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier];


         NSString* path = [[NSBundle mainBundle] pathForResource:@"MKAnnotation" ofType:@"png"];
         UIImage* im = [[UIImage alloc] initWithContentsOfFile:path];

         annotationView.image= im;//you can set your image here.

         annotationView.enabled = YES;
         annotationView.canShowCallout = YES;
         //delete the flagged Locations
         [self performSelectorOnMainThread:@selector(deletePin:) withObject:annotation2.name waitUntilDone:NO];
     }
return annotationView;

}

-(void)deletePin:(NSString *)stationCode{
    for (PlayerLocation *annotation in _mapView.annotations) {
        if ([annotation.name isEqualToString:stationCode]){  
            if (annotation.decomission==YES)
            [_mapView removeAnnotation:annotation];
        }
    }
}

这可以帮助您解决问题。

MKAnnotation显示默认引脚而不是自己的Image，尝试了一切

2 个答案: