子类化MKAnnotation并将对象添加到MapView

Question

I try to subclass the MKAnnotation protocol so I can add my own Store object to the MapView as Annotation

Store.h:

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

@interface Store : NSObject <MKAnnotation> {

    NSString *storeType;
    NSString *storeName;
    NSString *storeAddress;
    NSString *storeZip;
    NSString *storeCity;
    NSString *storeLinks;
    NSString *storeBrands;
    UIImage *storePicture;
    NSString *storeDescription;
    NSString *storeLatitude;
    NSString *storeLongitude;
}

@property (nonatomic, retain) NSString *storeType;
@property (nonatomic, retain) NSString *storeName;
@property (nonatomic, retain) NSString *storeAddress;
@property (nonatomic, retain) NSString *storeZip;
@property (nonatomic, retain) NSString *storeCity;
@property (nonatomic, retain) NSString *storeLinks;
@property (nonatomic, retain) NSString *storeBrands;
@property (nonatomic, retain) UIImage *storePicture;
@property (nonatomic, retain) NSString *storeDescription;
@property (nonatomic, retain) NSString *storeLatitude;
@property (nonatomic, retain) NSString *storeLongitude;

@end

Store.m:

#import "Store.h"

@implementation Store

@synthesize storeType, storeName, storeAddress, storeBrands, storeCity, storeLatitude, storeLinks, storeLongitude, storeZip, storePicture, storeDescription;


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

@end

ViewController.m (where I try to add the Store object as Annotation to the MapView:

for(Store *store in allStores) {
    NSString *location = [store storeAddress];
    location = [location stringByAppendingFormat:@", "];
    location = [location stringByAppendingFormat:[store storeZip]];
    location = [location stringByAppendingFormat:@" "];
    location = [location stringByAppendingFormat:[store storeCity]];

    CLLocationCoordinate2D annotationCoord;
    annotationCoord.latitude = [[store storeLatitude] floatValue];
    annotationCoord.longitude = [[store storeLongitude] floatValue];

    store.coordinate = annotationCoord;

    [self.mapView addAnnotation:store];
}

Error:

-[Store setCoordinate:]: unrecognized selector sent to instance 0x1742a9600
2014-10-29 14:54:01.992 TestMap[10417:2312661] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Store setCoordinate:]: unrecognized selector sent to instance 0x1742a9600'

Question:

• How can I add the Store object as Annotation to the MapView?
• How do I set the title and the subtitle of the annotation?

Answer 1

Your Store class needs a CLLocationCoordinate2D property named coordinate if you plan on not having any custom setters and getters, or setters and getters for that property if you do plan on having custom ones.

Title and subtitle are set similarily, either add properties named title and subtitle and they will be used automatically, or add getters for these two to return whatever text you like.

There's more detail here .

PS Ever since we got ARC, there is no need to synthesize all of your properties, so that line can be ommited. Additionally, you might want to consider not using iVars, and moving your properties to the .m file in the interface extension, unless you need them to be public.