更改地图图钉（颜色或图像）

Question

我知道这是一个经常被问到的问题。一段时间以来，我一直在阅读有关此问题的许多问题。我希望有人能用更简单的方法使用我必须用图像替换地图上的图钉的代码。我对目标 c 仍然很陌生。我拥有的代码非常简短。我在网上找到的大部分用于在地图上张贴图钉的内容都很长而且很长。我的地图视图有以下类和控制器：

LocationsViewController.h

#import "TechBookAppDelegate.h"
#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>


@interface LocationsViewController : UIViewController <MKMapViewDelegate>
{

    IBOutlet MKMapView *worldView;
    IBOutlet UIActivityIndicatorView *activityIndicator;

}
@end

LocationsViewController.m

 #import "LocationsViewController.h"
#import "MapAnnotation.h"
@interface LocationsViewController ()


@end

@implementation LocationsViewController


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Initialization code


    }
    return self;
}



- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.


    CLLocationCoordinate2D wisconsin = {.latitude =  xx.xxxxxxx, .longitude =  -xx.xxxxxx};
    CLLocationCoordinate2D pennsyvainia = {.latitude =  xx.xxxxxxx, .longitude =  -xx.xxxxxx};
    CLLocationCoordinate2D nevada = {.latitude =  xx.xxxxxxx, .longitude =  -xx.xxxxxx};
    CLLocationCoordinate2D texas = {.latitude =  xx.xxxxxxx, .longitude =  -xx.xxxxxx};
    MapAnnotation *pinWI = [[MapAnnotation alloc] initWithCoordinate: wisconsin];
    MapAnnotation *pinPA = [[MapAnnotation alloc] initWithCoordinate: pennsyvainia];
    MapAnnotation *pinNV = [[MapAnnotation alloc] initWithCoordinate: nevada];
    MapAnnotation *pinTX = [[MapAnnotation alloc] initWithCoordinate: texas];

    [worldView addAnnotation:pinTX];
    [worldView addAnnotation:pinNV];
    [worldView addAnnotation:pinWI];
    [worldView addAnnotation:pinPA];


}

MapAnnotation.h

  #import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>

@interface MapAnnotation : NSObject <MKAnnotation> {
    CLLocationCoordinate2D _coordinate;
    MKAnnotationView *mapView;
}

- (id)initWithCoordinate:(CLLocationCoordinate2D)coordinate;

@end

MapAnnotation.m

#import "MapAnnotation.h"
#import "LocationsViewController.h"

@implementation MapAnnotation
@synthesize coordinate = _coordinate;

- (id)initWithCoordinate:(CLLocationCoordinate2D)coordinate
{
    self = [super init];

    if (self != nil)
    {
        _coordinate = coordinate;
    }

    return self;
}
@end

我尝试过实现类似的方法：

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

使用各种类型的代码，但无济于事。不知道我做错了什么。没有比我目前在网上看到的更短的方法来做我在想的事情。

我希望有类似的东西：

MapAnnotation *pinWI = [[[MapAnnotation alloc] initWithCoordinate: wisconsin] initWithPinImage:@"imagename.png"];

或者我可以实现类似的东西： pinWI:MKPinAnnotationColorGreen; 仅定义了图像位置？

或类似的东西。提前感谢大家对新手的帮助和耐心。

我真的需要将图钉更改为自定义图像。我尝试过的一种编码模式是这样的：

    - (MKAnnotationView *)mapView:(MKMapView *)map viewForAnnotation:(id <MKAnnotation>)annotation
{
    static NSString *AnnotationViewID = @"annotationViewID";

    MKAnnotationView *annotationView = (MKAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:AnnotationViewID];

    if (annotationView == nil)
    {
        annotationView = [[[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:AnnotationViewID] autorelease];
    }

    annotationView.image = [UIImage imageNamed:@"location.png"];
    annotationView.annotation = annotation;

    return annotationView;
}

工作代码：

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

    static NSString *AnnotationViewID = @"annotationViewID";

    MKAnnotationView *annotationView = (MKAnnotationView *)[worldView dequeueReusableAnnotationViewWithIdentifier:AnnotationViewID];

    if (annotationView == nil)
    {
        annotationView = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:AnnotationViewID];
    }

    annotationView.image = [UIImage imageNamed:@"locations_marker.png"];
    annotationView.annotation = annotation;

    return annotationView;
}

Answer 1

将类型属性（example-firstPin、secondPin、thirdPin 等）添加到您的自定义MapViewAnnotation 类中。

MapViewAnnotation *newAnnotation = [[MapViewAnnotation alloc] init...
newAnnotation.type = @"firstPin";  // <-- set property in annotation
[self.mapView addAnnotation:newAnnotation];

并在您的 - (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation 方法中进行简单检查

MapViewAnnotation *mvAnn = (MapViewAnnotation *)annotation;
if ([mvAnn.type isEqualToString:@"firstPin"])
{
    annView.pinColor = MKPinAnnotationColorGreen;
}
else if ([mvAnn.type isEqualToString:@"secondPin"])
{
    annView.pinColor = MKPinAnnotationColorRed;
}
else if ([mvAnn.type isEqualToString:@"thirdPin"])
{
    annView.pinColor = MKPinAnnotationColorOrange;
}