MKAnnotationView
在异步请求完成并包含有关注释状态的信息后,我无法找到更新自定义图像的方法。到目前为止,我有这个:
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation {
static NSString *identifier = @"EstacionEB";
if ([annotation isKindOfClass:[EstacionEB class]]) {
EstacionEB *location = (EstacionEB *) annotation;
CustomPin *annotationView = (CustomPin *) [_mapita dequeueReusableAnnotationViewWithIdentifier:identifier];
if (annotationView == nil) {
annotationView = [[CustomPin alloc] initWithAnnotation:annotation reuseIdentifier:identifier];
} else {
annotationView.annotation = annotation;
}
UIImage * image = [UIImage imageNamed:[NSString stringWithFormat:@"%@.png", [location elStatus]]];
annotationView.enabled = YES;
annotationView.canShowCallout = YES;
annotationView.image = image;
NSDictionary *temp = [[NSDictionary alloc]
initWithObjects:[NSArray arrayWithObjects:annotationView, location, nil]
forKeys:[NSArray arrayWithObjects:@"view", @"annotation", nil]
];
//This array is synthesized and inited in my controller's viewDidLoad
[self.markers setObject:temp forKey:location.eid];
return annotationView;
}
return nil;
}
不久之后,我做了一个请求,结果是一个 NSDictionary,我正在尝试执行以下操作,这两个元素都返回 null:
- (void)updateStation:(NSString *)eid withDetails:(NSDictionary *)details
{
NSInteger free = [details objectForKey:@"free"];
NSInteger parkings = [details objectForKey:@"parkings"];
NSDictionary *storedStations = [self.markers objectForKey:eid];
CustomPin *pin = [storedStations objectForKey:@"view"]; //nil
EstacionEB *station = [referencia objectForKey:@"annotation"]; //nil as well
[station setSubtitle:free];
NSString *status;
if( free==0 ){
status = @"empty";
} else if( (free.intValue>0) && (parkings.intValue<=3) ){
status = @"warning";
} else {
status = @"available";
}
UIImage * image = [UIImage imageNamed:[NSString imageWithFormat:@"%@.png", status]];
pin.image = image;
}
这不会产生任何错误(假设我正确粘贴和转换了所有内容),但是 NSMutableDictionary 应该包含我的自定义 MKAnnotationView 和 MKAnnotation,但是即使我在请求完成之前将它们全部记录并且它正确显示,当请求完成时好像 MKAnnotationView 和 MKAnnotation 都不是我所期望的,因此,我无法修改注释以更改图像或更新注释视图。
任何想法,将不胜感激!