我想获取当前位置的地址并将其设置为注释的标题。但它没有用。我认为这是因为阻止,但我不知道如何解决它。任何帮助将不胜感激。最相关的代码如下:
WhereAmIAnnotation.h
#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
@interface WhereAmIAnnotation : NSObject <MKAnnotation>
{
CLLocation *myLocation;
NSString *addr;
}
@property (nonatomic, retain) CLLocation *myLocation;
@property (nonatomic, copy) NSString *addr;
@end
WhereAmIAnnotation.m
#import "WhereAmIAnnotation.h"
@implementation WhereAmIAnnotation
@synthesize myLocation, addr;
- (CLLocationCoordinate2D)coordinate;
{
return self.myLocation.coordinate;
}
- (NSString *)title
{
return self.addr;
}
@end
MapViewController.m
- (IBAction)gotoCurrentLocation{
self.mapView.showsUserLocation = YES;//a bar button linked with this action
}
- (void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation
{
CLLocation *currentLocation = userLocation.location;
MKCoordinateRegion newRegion;
newRegion.center = currentLocation.coordinate;
newRegion.span.latitudeDelta = 0.02;
newRegion.span.longitudeDelta = 0.02;
[self.mapView setRegion:newRegion animated:YES];
WhereAmIAnnotation *whereAmIAnnotation = [[WhereAmIAnnotation alloc] init];
whereAmIAnnotation.myLocation = currentLocation;
whereAmIAnnotation.addr = [self addrAtLocation:currentLocation];
[self.mapView addAnnotation:whereAmIAnnotation];
self.mapView.showsUserLocation = NO;
}
- (NSString *)addrAtLocation:(CLLocation *)location{
[self.geocoder reverseGeocodeLocation:location completionHandler:^(NSArray *placemark, NSError *error) {
CLPlacemark *topResult = [placemark objectAtIndex:0];
self.addr = [NSString stringWithFormat:@"%@ %@ %@ %@", topResult.country, topResult.locality, topResult.subLocality, topResult.thoroughfare];
}];
return self.addr;
}
我应该实现这个方法
- (MKAnnotationView *)mapView:(MKMapView *)theMapView viewForAnnotation:(id )annotation{}
抱歉这个愚蠢的问题!
答案 0 :(得分:3)
在异步块中修改地址时返回地址。您应该在块内移动返回,或者创建一个协议来处理将此信息传递回调用者。
将块更改为:
- (void)addrAtLocation:(CLLocation *)location{
[self.geocoder reverseGeocodeLocation:location completionHandler:^(NSArray *placemark, NSError *error) {
CLPlacemark *topResult = [placemark objectAtIndex:0];
whereAmIAnnotation.addr = [NSString stringWithFormat:@"%@ %@ %@ %@", topResult.country, topResult.locality, topResult.subLocality, topResult.thoroughfare];
}];
}
然后将whereAmIAnnotation
作为成员变量。你明白为什么这会解决你的问题吗?
答案 1 :(得分:0)
创建.h文件
@interface MapPinClass : NSObject <MKAnnotation>{
CLLocationCoordinate2D coordinate;
NSString *title;
NSString *subtitle,*color,*index,*locationId;
}
@property (nonatomic, assign) CLLocationCoordinate2D coordinate;
@property (nonatomic, copy) NSString *title;
@property (nonatomic, copy) NSString *subtitle,*color,*index,*locationId;
创建.m文件
@implementation MapPinClass
@synthesize coordinate,title,subtitle,color,index,locationId;
-(void)dealloc{
[title release];
[super dealloc];
}
编写设置
的代码 MapPinClass *ann = [[MapPinClass alloc] init];
ann.title = AppMain.Heading;
ann.subtitle = AppMain.Detail;
ann.coordinate = region.center;
[myMapView addAnnotation:ann];
答案 2 :(得分:0)
我应该实现这个方法
- (MKAnnotationView *)mapView:(MKMapView *)theMapView viewForAnnotation:(id <MKAnnotation>)annotation{}
抱歉这个愚蠢的问题。