为什么没有调用MKMapView委托方法?

时间:2011-04-26 21:25:26

标签: objective-c delegates mkmapview mkannotation

我对iphone开发很新,我正在尝试注释地图。我已经能够在硬编码坐标的地图上获得3个位置点,现在我正在尝试自定义引脚。我知道要这样做,你需要实现:-(MKAnnotationView *)mapView:(MKMapView *)mV viewForAnnotation:(id <MKAnnotation>)annotation {委托方法。

出于某种原因,我甚至无法得到它。这是我在控制器头中的内容:

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

@interface TestViewController : UIViewController <MKMapViewDelegate> {
    MKMapView *mapView;
    NSMutableArray *mapAnnotations;
    float results_lat[3];
    float results_long[3];
    NSMutableArray *results_title;
    NSMutableArray *Arts;

}
@property (nonatomic, retain) IBOutlet MKMapView *mapView;
@property (nonatomic, retain) NSMutableArray *mapAnnotations;

@end

以下是我在控制器实现中的内容:

- (void)viewDidLoad {
    results_long[0] = -122.477989;
    results_lat[0] = 37.810000;
    results_long[1] = -122.480000;
    results_lat[1] = 37.820000;
    results_long[2] = -122.4850000;
    results_lat[2] = 37.830000;

    self.mapAnnotations = [[NSMutableArray alloc] initWithCapacity:3];
    Arts = [[NSMutableArray alloc] initWithCapacity:3];
    for(int x = 0; x<3; x++)
    {
        // creates an ArtPiece object and sets its lat and long
        ArtPiece *a = [[ArtPiece alloc] init];
        a.longitude = [NSNumber numberWithDouble:results_long[x]];
        a.latitude = [NSNumber numberWithDouble:results_lat[x]];
        a.title = @"please show up";
        // add objects to annotation array
        [self.mapAnnotations insertObject:a atIndex:x];
        [a release];

    }
    // center screen on cali area
    [self gotoLocation];
    for(int x = 0; x<3; x++)
    {
        [mapView addAnnotations:mapAnnotations];
    }
}

-(MKAnnotationView *)mapView:(MKMapView *)mV viewForAnnotation:(id <MKAnnotation>)annotation {
    NSLog(@"This is not printing to to console...");
    MKPinAnnotationView *pinView = nil; 
    if(annotation != mapView.userLocation) 
    {
        static NSString *defaultPinID = @"com.invasivecode.pin";
        pinView = (MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:defaultPinID];
        if ( pinView == nil ) pinView = [[[MKPinAnnotationView alloc]
                                          initWithAnnotation:annotation reuseIdentifier:defaultPinID] autorelease];

        pinView.pinColor = MKPinAnnotationColorPurple; 
        pinView.canShowCallout = YES;
        pinView.animatesDrop = YES;
    } 
    else {
        [mapView.userLocation setTitle:@"I am here"];
    }
    return pinView;
}

这是ArtPiece类的实现:

   #import "TestViewController.h"
    #import "ArtPiece.h"
    #import <MapKit/MapKit.h>
    #import <CoreData/CoreData.h>

    @implementation ArtPiece

    @synthesize title, artist, series, description, latitude, longitude;

    - (CLLocationCoordinate2D)coordinate
    {
        CLLocationCoordinate2D theCoordinate;
        theCoordinate.latitude = [self.latitude doubleValue];
        theCoordinate.longitude = [self.longitude doubleValue];
        return theCoordinate;
    }



    @end

这可能很简单。我的方法声明有问题吗?我是否宣布代表错了?我无法弄明白,再次,我对这个目标c /委托的东西很新。谢谢你的帮助。

1 个答案:

答案 0 :(得分:3)

addAnnotations方法需要符合MKAnnotation协议的NSArray对象。

您正在添加ArtPiece类型的对象,这些对象似乎没有实现具有coordinate属性(不是latitudelongitude属性)的MKAnnotation。

更新您的ArtPiece课程以符合MKAnnotation(或使用预定义的MKPointAnnotation课程)。但更新自定义类是一个更好的解决方法。