Objective C : Map Example

map.m

//
//  LocationViewController.m
//  BoxBox
//
//  Created by Warut Surapat on 12/19/11.
//  Copyright (c) 2011 StardustDream. All rights reserved.
//

#import "LocationViewController.h"
#import "GlobalData.h"
#import "URLHelper.h"
#import "MerchantLocation.h"
#import "NotifierHelper.h"
#import "Logger.h"
#import "SVProgressHUD.h"

#define kBgQueue dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0) 
#define METERS_PER_MILE 1609.344

@implementation LocationViewController{
  CLLocationCoordinate2D currentLocation;
}
@synthesize map;
@synthesize locationManager;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

#pragma mark - View lifecycle

/*
// Implement loadView to create a view hierarchy programmatically, without using a nib.
- (void)loadView
{
}
*/


- (void)viewDidUnload
{
  [self setMap:nil];
  [super viewDidUnload];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{ 
  return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
- (void)viewDidLoad
{
  [Logger logAll:@"LocationView:::Enter view"];
  [super viewDidLoad];
  
  locationManager = [[CLLocationManager alloc] init];
  locationManager.delegate = self;
  
  
  
  [SVProgressHUD showWithStatus:[GlobalData applicationTextForKey:@"BasicLoading"]];
  [self updateData];
  
}

- (void)viewWillAppear:(BOOL)animated {  
  
}


- (void) updateData{
  dispatch_async(kBgQueue, ^{
    NSString *target_url_string = [URLHelper URLStringWithBaseURL:[GlobalData locationURL] 
                                                       withSuffix:[NSArray arrayWithObjects:[GlobalData userId], nil]
                                                   withParameters:[NSArray arrayWithObjects:
                                                                   [NSString stringWithFormat:@"ApplicationKey=%@",[GlobalData applicationKey]],
                                                                   [NSString stringWithFormat:@"AuthenticationKey=%@",[GlobalData authenticationKey]],
                                                                   [NSString stringWithFormat:@"Radius=%d",10],
                                                                   //[NSString stringWithFormat:@"Latitude=%f", currentLocation.latitude],
                                                                   //[NSString stringWithFormat:@"Longtitude=%f", currentLocation.longitude],
                                                                   [NSString stringWithFormat:@"Latitude=%f",13.730313],
                                                                   [NSString stringWithFormat:@"Longitude=%f",100.494937],
                                                                   nil]];
    NSURL *target_url = [NSURL URLWithString:target_url_string];
    
    NSData *data = [NSData dataWithContentsOfURL:target_url];
    [self performSelectorInBackground:@selector(plotMap:) withObject:data];
    //    [self performSelectorOnMainThread:@selector(plotMap:) 
    //                           withObject:data waitUntilDone:YES];
  });
}



- (void) plotMap:(NSData *)respondedData{
  if(respondedData != nil){
    NSError *error;
    NSDictionary *data_dic = [NSJSONSerialization 
                              JSONObjectWithData:respondedData
                              options:kNilOptions 
                              error:&error];
    NSNumber *returned_code = [data_dic objectForKey:@"StatusCode"];
    
    if([@"200" isEqualToString:[returned_code stringValue]]){
      NSArray *data = [data_dic objectForKey:@"Items"];
      for (NSDictionary * item in data){
        NSDictionary *location = [item objectForKey:@"Location"];
        NSNumber *latitude = [location objectForKey:@"Latitude"];
        NSNumber *longitude = [location objectForKey:@"Longitude"];
        NSString *name = [NSString stringWithFormat:@"%@\n%@",
                          [item objectForKey:@"MerchantName"],
                          [item objectForKey:@"BranchName"]];
        
        CLLocationCoordinate2D coordinate;
        coordinate.latitude = latitude.doubleValue;
        coordinate.longitude = longitude.doubleValue; 
        
        MerchantLocation *annotation = [[MerchantLocation alloc] initWithName:name coordinate:coordinate];
        [map addAnnotation:annotation];
        [Logger logAll:@"LocationView:::Finished loading data"];
        [locationManager startUpdatingLocation];
        [SVProgressHUD dismiss];
      }
    }
    else{
      [SVProgressHUD dismiss];
      [NotifierHelper showBasicError:self];
      [Logger logAll:@"LocationView:::Failed to load data"];
    }
  }
  else{
    [SVProgressHUD dismiss];
    [NotifierHelper showBasicError:self];
    [Logger logAll:@"LocationView:::Failed to load data"];
  }
}

- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation {
  
  static NSString *identifier = @"MyLocation";   
  if ([annotation isKindOfClass:[MerchantLocation class]]) {
    
    MKPinAnnotationView *annotationView = (MKPinAnnotationView *) [map dequeueReusableAnnotationViewWithIdentifier:@"PinMerchantLocation"];
    if (annotationView == nil) {
      annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:identifier];
    } else {
      annotationView.annotation = annotation;
    }
    
    annotationView.enabled = YES;
    annotationView.canShowCallout = YES;
    annotationView.image=[UIImage imageNamed:@"map_location.png"];//here we use a nice image instead of the default pins
    
    return annotationView;
  }
  
  return nil;    
}



- (IBAction)refresh:(id)sender {
  [Logger logAll:@"LocationView:::Refresh data"];
  [self updateData];
}

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{  
  //map.showsUserLocation=TRUE;
  
  // zoom to  a specific area
  
  //  currentLocation.latitude = newLocation.coordinate.latitude;
  //  currentLocation.longitude = newLocation.coordinate.longitude;
  //  map.delegate=self;
  //[self zoomToCurrentLocation];
  
  CLLocationCoordinate2D zoomLocation;
  zoomLocation.latitude = map.userLocation.coordinate.latitude;//13.730313;
  zoomLocation.longitude= map.userLocation.coordinate.longitude;//100.494937;
  MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(zoomLocation, 3.0*METERS_PER_MILE, 3.0*METERS_PER_MILE);
  MKCoordinateRegion adjustedRegion = [map regionThatFits:viewRegion];                
  
  [map setRegion:adjustedRegion animated:YES];      
  [locationManager stopUpdatingLocation];
}
- (void) zoomToCurrentLocation{
  MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(
                                                                     currentLocation, 40*METERS_PER_MILE, 40*METERS_PER_MILE);
  MKCoordinateRegion adjustedRegion = [map regionThatFits:viewRegion];    
  map.autoresizingMask = (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight);
  [map setRegion:adjustedRegion animated:YES]; 
  
  //  MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(currentLocation, 50000, 50000);
  //  [map setRegion:region animated:YES];
  
}
@end