如何创建符合 <MKAnnotation> 协议的自定义 class
how to create a custom class that conforms to <MKAnnotation> protocol
我有一张显示所有餐厅对象的地图。我正在尝试将餐厅对象传递给地图注释,以便我可以显示包含所有餐厅信息的详细视图。经过研究,我试图创建一个符合协议的 class,但是我无法在地图中放置注释。这是我的代码:
RestaurantAnnotationClass.h(自定义 class):
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
#import "Restaurant.h"
static NSString *restaurantAnnotationIdentifier = @"restaurantAnnotationIdentifier";
@interface RestaurantAnnotation : NSObject <MKAnnotation>
@property (copy, nonatomic) NSString *title;
@property (copy, nonatomic) NSString *subtitle;
@property (nonatomic) CLLocationCoordinate2D coordinate;
@property (nonatomic, strong) Restaurant *restaurant;
- (id)initWithTitle:(NSString *)newTitle subtitle:(NSString *)newSubtitle restaurant:(Restaurant *)newRestaurant location:(CLLocationCoordinate2D)location;
- (MKAnnotationView *)annotationView;
@end
RestaurantAnnotationClass.m
#import "RestaurantAnnotation.h"
@implementation RestaurantAnnotation
- (id)initWithTitle:(NSString *)newTitle subtitle:(NSString *)newSubtitle restaurant:(Restaurant *)newRestaurant location:(CLLocationCoordinate2D)location {
self = [super init];
if (self) {
self.title = newTitle;
self.coordinate = location;
self.subtitle = newSubtitle;
self.restaurant = newRestaurant;
}
return self;
}
- (MKAnnotationView *)annotationView {
MKAnnotationView *annotationView = [[MKAnnotationView alloc] initWithAnnotation:self reuseIdentifier:restaurantAnnotationIdentifier];
annotationView.enabled = YES;
annotationView.canShowCallout = YES;
annotationView.rightCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
return annotationView;
}
@end
我的地图控制器
- (NSArray *)convertRestaurantToMKAnnotationsFromArray:(NSArray *)restaurantsArray {
NSMutableArray *mkPointAnnotations = [NSMutableArray new];
double mileToMeters = 1609.344;
CLLocation *userLocation = [[CLLocation alloc] initWithLatitude:self.userCurrentLocation.coordinate.latitude longitude:self.userCurrentLocation.coordinate.longitude];
for (Restaurant *restaurant in restaurantsArray) {
CLLocation *restaurantLocation = [[CLLocation alloc] initWithLatitude:restaurant.geoLocation.latitude longitude:restaurant.geoLocation.longitude];
RestaurantAnnotation *newRestaurantAnnotation = [[RestaurantAnnotation alloc] initWithTitle:restaurant.name subtitle:[NSString stringWithFormat:@"%.02f",[userLocation distanceFromLocation:restaurantLocation] / mileToMeters] restaurant:restaurant location:CLLocationCoordinate2DMake(restaurant.geoLocation.latitude, restaurant.geoLocation.longitude)];
[mkPointAnnotations addObject: newRestaurantAnnotation];
}
return mkPointAnnotations;
}
我在这里实现 vuewforannotation 方法
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation {
if ([annotation isKindOfClass:[MKUserLocation class]])
return nil;
if ([annotation isKindOfClass:[RestaurantAnnotation class]]) {
RestaurantAnnotation *restaurant = (RestaurantAnnotation *)annotation;
MKAnnotationView *restaurantAnnotationView = [mapView dequeueReusableAnnotationViewWithIdentifier:restaurantAnnotationIdentifier];
if (restaurantAnnotationView == nil)
restaurantAnnotationView = restaurant.annotationView;
else
restaurantAnnotationView.annotation = annotation;
return restaurantAnnotationView;
} else
return nil;
}
提前致谢
我在应用 viewForAnnotation 方法时犯了一个错误,现在这是我的代码
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation {
if ([annotation isKindOfClass:[MKUserLocation class]]) {
return nil;
}
if ([annotation isKindOfClass:[RestaurantAnnotation class]]) {
RestaurantAnnotation *restauntAnnotation = (RestaurantAnnotation *)annotation;
MKAnnotationView *restaurantAnnotationView = [mapView dequeueReusableAnnotationViewWithIdentifier:restaurantAnnotationIdentifier];
if (restaurantAnnotationView == nil) {
restaurantAnnotationView = restauntAnnotation.annotationView;
} else {
restaurantAnnotationView.annotation = annotation;
return restaurantAnnotationView;
}
}
return nil;
我有一张显示所有餐厅对象的地图。我正在尝试将餐厅对象传递给地图注释,以便我可以显示包含所有餐厅信息的详细视图。经过研究,我试图创建一个符合协议的 class,但是我无法在地图中放置注释。这是我的代码:
RestaurantAnnotationClass.h(自定义 class):
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
#import "Restaurant.h"
static NSString *restaurantAnnotationIdentifier = @"restaurantAnnotationIdentifier";
@interface RestaurantAnnotation : NSObject <MKAnnotation>
@property (copy, nonatomic) NSString *title;
@property (copy, nonatomic) NSString *subtitle;
@property (nonatomic) CLLocationCoordinate2D coordinate;
@property (nonatomic, strong) Restaurant *restaurant;
- (id)initWithTitle:(NSString *)newTitle subtitle:(NSString *)newSubtitle restaurant:(Restaurant *)newRestaurant location:(CLLocationCoordinate2D)location;
- (MKAnnotationView *)annotationView;
@end
RestaurantAnnotationClass.m
#import "RestaurantAnnotation.h"
@implementation RestaurantAnnotation
- (id)initWithTitle:(NSString *)newTitle subtitle:(NSString *)newSubtitle restaurant:(Restaurant *)newRestaurant location:(CLLocationCoordinate2D)location {
self = [super init];
if (self) {
self.title = newTitle;
self.coordinate = location;
self.subtitle = newSubtitle;
self.restaurant = newRestaurant;
}
return self;
}
- (MKAnnotationView *)annotationView {
MKAnnotationView *annotationView = [[MKAnnotationView alloc] initWithAnnotation:self reuseIdentifier:restaurantAnnotationIdentifier];
annotationView.enabled = YES;
annotationView.canShowCallout = YES;
annotationView.rightCalloutAccessoryView = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
return annotationView;
}
@end
我的地图控制器
- (NSArray *)convertRestaurantToMKAnnotationsFromArray:(NSArray *)restaurantsArray {
NSMutableArray *mkPointAnnotations = [NSMutableArray new];
double mileToMeters = 1609.344;
CLLocation *userLocation = [[CLLocation alloc] initWithLatitude:self.userCurrentLocation.coordinate.latitude longitude:self.userCurrentLocation.coordinate.longitude];
for (Restaurant *restaurant in restaurantsArray) {
CLLocation *restaurantLocation = [[CLLocation alloc] initWithLatitude:restaurant.geoLocation.latitude longitude:restaurant.geoLocation.longitude];
RestaurantAnnotation *newRestaurantAnnotation = [[RestaurantAnnotation alloc] initWithTitle:restaurant.name subtitle:[NSString stringWithFormat:@"%.02f",[userLocation distanceFromLocation:restaurantLocation] / mileToMeters] restaurant:restaurant location:CLLocationCoordinate2DMake(restaurant.geoLocation.latitude, restaurant.geoLocation.longitude)];
[mkPointAnnotations addObject: newRestaurantAnnotation];
}
return mkPointAnnotations;
}
我在这里实现 vuewforannotation 方法
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation {
if ([annotation isKindOfClass:[MKUserLocation class]])
return nil;
if ([annotation isKindOfClass:[RestaurantAnnotation class]]) {
RestaurantAnnotation *restaurant = (RestaurantAnnotation *)annotation;
MKAnnotationView *restaurantAnnotationView = [mapView dequeueReusableAnnotationViewWithIdentifier:restaurantAnnotationIdentifier];
if (restaurantAnnotationView == nil)
restaurantAnnotationView = restaurant.annotationView;
else
restaurantAnnotationView.annotation = annotation;
return restaurantAnnotationView;
} else
return nil;
}
提前致谢
我在应用 viewForAnnotation 方法时犯了一个错误,现在这是我的代码
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation {
if ([annotation isKindOfClass:[MKUserLocation class]]) {
return nil;
}
if ([annotation isKindOfClass:[RestaurantAnnotation class]]) {
RestaurantAnnotation *restauntAnnotation = (RestaurantAnnotation *)annotation;
MKAnnotationView *restaurantAnnotationView = [mapView dequeueReusableAnnotationViewWithIdentifier:restaurantAnnotationIdentifier];
if (restaurantAnnotationView == nil) {
restaurantAnnotationView = restauntAnnotation.annotationView;
} else {
restaurantAnnotationView.annotation = annotation;
return restaurantAnnotationView;
}
}
return nil;