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objective-ccocoa-touchiphone-sdk-3.0mapkitmkannotation

How to Add Multiple Placemarks and Annotations to Map


I have a class that loads a map, get my current location, then does a search on my database for companies in an area based on a zip code radius. I am doing a for loop to loop through each address, forward geocode, now I want to put a placemark and annotation for each location. How can I accomplish this. Here is my code:

- (void)locationUpdate:(CLLocation *)location {
locationLabel.text = [location description];
NSNumber *lat = [[NSString alloc] initWithFormat:@"%g", location.coordinate.latitude];
float latValue = [lat floatValue];
NSNumber *lng = [[NSString alloc] initWithFormat:@"%g", location.coordinate.longitude];
float lngValue = [lng floatValue];

mapView=[[MKMapView alloc] initWithFrame:self.view.bounds];
mapView.showsUserLocation=TRUE;
mapView.mapType=MKMapTypeStandard;
mapView.delegate=self;

/*Region and Zoom*/
MKCoordinateRegion region;
MKCoordinateSpan span;
span.latitudeDelta=0.2;
span.longitudeDelta=0.2;

CLLocationCoordinate2D location1=mapView.userLocation.coordinate;

location1.latitude=latValue;
location1.longitude=lngValue;
region.span=span;
region.center=location1;

/*Geocoder Stuff*/

geoCoder=[[MKReverseGeocoder alloc] initWithCoordinate:location1];
geoCoder.delegate=self;
[geoCoder start];

[mapView setRegion:region animated:TRUE];
[mapView regionThatFits:region];
[self.view insertSubview:mapView atIndex:0];
}
- (void)reverseGeocoder:(MKReverseGeocoder *)geoCoder didFindPlacemark:(MKPlacemark *)placemark
{
NSDictionary *zipDic = [placemark addressDictionary];
NSString *zipCode = [zipDic objectForKey:@"ZIP"];
NSString *post = [NSString stringWithFormat:@"zip=%@", zipCode];
NSString *hostString = @"https://www.mysite.com/searchzip.php?";

// Append string and add percent escapes
hostString = [[hostString stringByAppendingString:post]    stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *hostURL = [NSURL URLWithString:hostString];
NSString *jsonString = [[NSString alloc] initWithContentsOfURL:hostURL];
self.zipArray = [jsonString JSONValue]; 
NSLog(@"%@", zipArray);
for (NSString *sZip in zipArray) {
     NSString *lblAddress = [sZip objectForKey:@"address"];
    NSString *hostStr = [[@"http://maps.google.com/maps/geo?q="   stringByAppendingString:lblAddress]stringByAppendingString:@"&key=ABQIAAAA1KqXKe5yJPkX6ii6Ud    K-0RSIvIZDM4KnjydqrehqKK56hFf_fxQc0uyCKoh-4i77-5B0Qfc8Gs223Q&sensor=false&output=json"];
    hostStr = [hostStr  stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

    NSURL *hostURL = [NSURL URLWithString:hostStr];
    NSString *jsonString = [[NSString alloc] initWithContentsOfURL:hostURL];

    SBJSON *parser = [[SBJSON alloc] init];

    // parse the JSON string into an object - assuming json_string is a NSString of JSON data
    NSArray *object = [parser objectWithString:jsonString error:nil];

    NSArray *placemarks = [object objectForKey:@"Placemark"];
    NSDictionary *mark = [placemarks objectAtIndex:0];
    NSDictionary *point = [mark objectForKey:@"Point"];
    NSArray *coordinates = [point objectForKey:@"coordinates"];
    NSNumber *lat = (NSNumber*)[coordinates objectAtIndex:0];
    float latValue = [lat floatValue];
    NSNumber *lon = (NSNumber*)[coordinates objectAtIndex:1];
    float lonValue = [lon floatValue];

          //Here is where I would put placemarks and annotations
}

}
- (void)locationError:(NSError *)error {
locationLabel.text = [error description];
}

@end

I tried...

CLLocationCoordinate2D location = {latitude: latValue, longitude: lonValue};
    return location;

But obviously its wrong. I tried creating a seperate MapAnnotation class to handle the annotations like so:

#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
#import "AgencyViewController.h"
@interface MapAnnotation : NSObject<MKAnnotation> {
CLLocationCoordinate2D coordinate;
NSString *subtitletext;
NSString *titletext;
}
@property (nonatomic, readonly) CLLocationCoordinate2D coordinate;
@property (readwrite, retain) NSString *titletext;
@property (readwrite, retain) NSString *subtitletext;
-(id)initWithCoordinate:(CLLocationCoordinate2D) coordinate;
- (NSString *)subtitle;
- (NSString *)title;
-(void)setTitle:(NSString*)strTitle;
-(void)setSubTitle:(NSString*)strSubTitle;

and implement it like so:

CLLocationCoordinate2D newCoord = {latitude: latValue, longitude: lonValue};

    MapAnnotation *addAnnotation = [[MapAnnotation alloc] initWithCoordinate:newCoord];  
    [addAnnotation setTitle:@"The Pin Title"];  
    [addAnnotation setSubTitle:@"The pin subtitle goes here"];  

    [mapView addAnnotation:addAnnotation];  

And that didnt work either...


Solution

  • Figured it out, needed to add

    - (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation {
    MKPinAnnotationView *pinView = (MKPinAnnotationView*)[mapView dequeueReusableAnnotationViewWithIdentifier:@"Prospects"];
    if(pinView == nil) {
        pinView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"Prospects"];
        pinView.pinColor = MKPinAnnotationColorGreen;
        pinView.animatesDrop = NO;
        pinView.canShowCallout = YES;
    } else {
        pinView.annotation = annotation;
    }
    return pinView;
    }
    

    Now I need to figure out how to change the color of my location pin.