Ios MapView Pin注释存在问题-缩放/平移地图/更改区域时，Pin会失去颜色

我有一个地图视图，显示现金点的位置。注释将被删除，并且可以单击标注以转到包含该位置更多详细信息的页面。有两种类型的现金点，免费和付费，免费现金点PIN是绿色的，另一种是红色的。别针掉落时，颜色正确。一切正常，直到我缩放到用户位置或地图的其他区域，然后当我返回到PIN时，它们的颜色格式已丢失，并且都是原始的红色

我假设这与地图下载分幅时重新加载有关，但没有正确地重新加载插脚，尽管我可能错了

任何帮助都将不胜感激

这是我的密码：

#import "CashPointMapViewController.h"
#import "PinDrop.h"
#import "CashPointDetailViewController.h"

@implementation CashPointMapViewController
@synthesize app, theCashList, mapview, ann, count, myArray, pinColor;

- (IBAction) getlocation { 

    MKCoordinateRegion region;
    region.center = self.mapview.userLocation.coordinate;
    region.span.longitudeDelta = 0.01f;
    region.span.longitudeDelta = 0.01f;
    [mapview setRegion:region animated:YES];
}

- (void)viewDidLoad {

    [super viewDidLoad];

    mapview.showsUserLocation = YES;

    [mapview setMapType:MKMapTypeStandard];
    [mapview setZoomEnabled:YES];
    [mapview setScrollEnabled:YES];

    MKCoordinateRegion region = { {0.0, 0.0 }, {0.0, 0.0 } };
    region.center.latitude = 53.801279;
    region.center.longitude = -1.548567;
    region.span.longitudeDelta = 0.3f;
    region.span.longitudeDelta = 0.3f;
    [mapview setRegion:region animated:YES];

    app = [[UIApplication sharedApplication]delegate];

    UIImage *locate = [UIImage imageNamed:@"location arrow white.png"];

    UIBarButtonItem *userlocatebutton = [[UIBarButtonItem alloc] initWithImage:locate     style:UIBarButtonItemStylePlain target:self action:@selector(getlocation)];

    self.navigationItem.rightBarButtonItem = userlocatebutton;

    [self performSelectorInBackground:@selector(annloop) withObject:self];

}


-(void) annloop {

    int i;
    for (i=0; i<=count-1; i = i+1) {
    theCashList = [myArray objectAtIndex:i];

    NSString *trimlat = [theCashList.lat stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
    NSString *trimlon = [theCashList.lon stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];

    double latdouble = [trimlat doubleValue];
    double londouble = [trimlon doubleValue];

    CLLocationCoordinate2D coord = {(latdouble),(londouble)};

    ann = [[PinDrop alloc] init];

    ann.index = i;

    ann.title = [theCashList.name stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];

    NSString *street = [theCashList.street stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
    NSString *town = [theCashList.town stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
    NSString *postcode = [theCashList.postcode stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];

    NSString *address = [[NSString alloc] initWithFormat:@"%@, %@, %@", street, town, postcode];

    ann.subtitle = address;
    ann.coordinate = coord;

    NSString *trimprice = [theCashList.price stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];

    if ([trimprice isEqualToString:@"Free"])
    {
        ann.price = 1;
    }
    else
    {
        ann.price = 0;
    }
    [mapview performSelectorOnMainThread:@selector(addAnnotation:) withObject:ann waitUntilDone:YES];
    }
}


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

    if ([annotation isKindOfClass:[MKUserLocation class]])
    return nil;

    MKPinAnnotationView *mypin = [[MKPinAnnotationView alloc]initWithAnnotation:ann reuseIdentifier:@"current"];
    mypin.backgroundColor = [UIColor clearColor];
    UIButton *goToDetail = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
    mypin.rightCalloutAccessoryView = goToDetail;
    mypin.draggable = NO;
    mypin.animatesDrop = TRUE;
    mypin.canShowCallout = YES;


    if (ann.price == 1)
    {
        mypin.pinColor = MKPinAnnotationColorGreen;
    }
    else
    {
        mypin.pinColor = MKPinAnnotationColorRed;
    }
    return mypin;
    }


- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view
calloutAccessoryControlTapped:(UIControl *)control {

   PinDrop *annView = view.annotation;
    CashPointDetailViewController *detailView = [[CashPointDetailViewController alloc]init];
    theCashList = [myArray objectAtIndex:annView.index];
    detailView.theCashList = theCashList;
    [self.navigationController pushViewController:detailView animated:YES];

}


- (void)viewDidUnload {

    [super viewDidUnload];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:   (UIInterfaceOrientation)interfaceOrientation {
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

@end

#导入“CashPointMapViewController.h”
#导入“PinDrop.h”
#导入“CashPointDetailViewController.h”
@CashPointMapViewController的实现
@综合应用程序、现金清单、地图视图、人工神经网络、计数、myArray、pinColor；
-（iAction）getlocation{
协调区域；
region.center=self.mapview.userLocation.coordinate；
region.span.longitudeDelta=0.01f；
region.span.longitudeDelta=0.01f；
[地图视图设置区域：区域动画：是]；
}
-（无效）viewDidLoad{
[超级视图下载]；
mapview.showsUserLocation=是；
[mapview setMapType:MKMapTypeStandard]；
[mapview SetZoomeEnabled:是]；
[地图视图设置可克隆：是]；
MKCoordinateRegion={0.0,0.0}，{0.0,0.0}；
region.center.lation=53.801279；
region.center.longitude=-1.548567；
region.span.longitudeDelta=0.3f；
region.span.longitudeDelta=0.3f；
[地图视图设置区域：区域动画：是]；
app=[[UIApplication sharedApplication]委托]；
UIImage*locate=[UIImage ImageName:@“location arrow white.png”]；
UIBarButtonItem*userlocatebutton=[[UIBarButtonItem alloc]initWithImage:locate样式：UIBarButtonItemStylePlain目标：自我操作：@selector（getlocation）]；
self.navigationItem.rightBarButtonItem=userlocatebutton；
[self-performSelectorInBackground:@selector（annloop）with object:self]；
}
-（void）循环{
int i；
对于（i=0；i而言，这与贴图重新加载分幅无关

问题是，
viewForAnnotation
委托中的代码使用的是
ann
对象，错误地假设只要调用委托方法，类实例级
ann
对象就会与之同步

viewForAnnotation
委托不一定按照添加注释的顺序调用，如果地图返回视图时需要重新显示注释，则可以为同一注释多次调用委托

当为先前添加的批注再次调用委托方法时，
ann
和
annotation
不再指向同一个对象。
ann
现在可能指向最后添加的批注，因此所有批注都变为其颜色

在该委托方法中，必须使用
annotation
参数，该参数是地图视图希望在当前调用中查看的注释的引用（可能与外部循环完全无关）

所以这一行：

MKPinAnnotationView *mypin = [[MKPinAnnotationView alloc] 
    initWithAnnotation:ann reuseIdentifier:@"current"];

应该是：

MKPinAnnotationView *mypin = [[MKPinAnnotationView alloc] 
    initWithAnnotation:annotation reuseIdentifier:@"current"];
                       ^^^^^^^^^^

检查注释的属性时，请使用
注释
参数（并将其强制转换到自定义类以获取自定义属性）：



一个单独的、不相关但强烈建议的建议是，通过使用
dequeueReusableAnnotationViewWithIdentifier
，实现注释视图重用。这将在有大量注释时提高性能。
swift 2.0有任何解决方案吗？
MKPinAnnotationView *mypin = [[MKPinAnnotationView alloc] 
    initWithAnnotation:annotation reuseIdentifier:@"current"];
                       ^^^^^^^^^^

PinDrop *ann = (PinDrop *)annotation;
//Note that this local "ann" is NOT the same as the class-level "ann".
//May want to use a different name to avoid confusion.
//The compiler may also warn you about this.

if (ann.price == 1)
...