ios - 更改 map 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，我一直在阅读这里的许多问题。我希望有人能有一种更简单的方法，使用我必须用图像替换 map 上的图钉的代码。我对 objective-c 还是很陌生。我的代码非常简短。我在网上找到的大多数用于将图钉张贴到 map 上的东西都很长而且很长。我的 map View 有以下类和 Controller :

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

我曾尝试实现与此类似的方法:

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

各种类型的代码，但无济于事。不确定我做错了什么。有没有比我到目前为止在网上看到的更短的方法来做我想做的事情。

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。在此先感谢大家对新手的帮助和耐心。

我真的需要将 pin 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。

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

在你的- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation方法进行简单检查

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;
}