Question

I’m a newbie to programming for iPhone, I’m following along this book.
I’m stuck at the example in Chapter 4, Delegation and Core Location.

Here’s the code I’ve written so far:
WhereamiAppdelegate.h

    #import <UIKit/UIKit.h>
    #import <CoreLocation/CoreLocation.h>

    @interface WhereamiAppDelegate : NSObject <UIApplicationDelegate, CLLocationManagerDelegate> {
        UIWindow *window;
        CLLocation *locationManager;

    }

    @property (nonatomic, retain) IBOutlet UIWindow *window;

    @end

And here is the implementation file:
I have only included the changes that I’ve made.
The entire file is here.

 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
    {
        // Create location manager.
        locationManager = [[CLLocation alloc] init];
        [locationManager setDelegate:self];
        [locationManager setDistanceFilter:kCLDistanceFilterNone];
        [locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
        [locationManager startUpdatingLocation];

    [self.window makeKeyAndVisible];
    return YES;
}

- (void)dealloc
{
    [locationManager setDelegate:nil];
    [_window release];
    [super dealloc];
}

- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation
{
    NSLog(@"%@",newLocation);
}

- (void)locationManager:(CLLocationManager *)manager
       didFailWithError:(NSError *)error
{
    NSLog(@"Couldn't find loaction %@",error);
}

XCode gives me a warning that says CLLocation may not respond to setDistanceFilter and other similar warnings.
I am clueless here, I have followed the book line to line.
I think that I haven’t implemented a necessary protocol or something.
Can someone please tell me what I’m doing wrong and how I should proceed further.

Answer 1

The class CLLocation is not the same as CLLocationManager. The former represents one location, while the latter is the manager class that handles configuring location updates for your application.