UIlabel doesn't update user current speed - ios

Question

been having this problem for a few days now and can't seem to find a solution for it. It's probably some very basic stuff but still can't come up with a solution. So I'm trying to have my uilabel update a user speed in a car or on bike. But When the UIlabel update, it doesn't update the correct value. Any help will be appreciated.
Heres my .h file
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>
#import <CoreLocation/CoreLocation.h>
#interface MainViewController : UIViewController <LoginDelegate,WEPopoverParentView,PopoverControllerDelegate,MainMenuDelegate,MKMapViewDelegate,UIActionSheetDelegate,UIAccelerometerDelegate, CLLocationManagerDelegate, NSObject>
{
AppDelegate *appDelegate;
IBOutlet MKMapView *userMap;
CLLocationManager *locationManager;
}
#property (strong, nonatomic) IBOutlet UILabel *speedView;
#property(nonatomic) int speedCount;
#property (nonatomic,retain) CLLocationManager *locationManager;
#property (nonatomic, strong) WEPopoverController *popoverController;
+ (NSString *) speedToMPH: (float) value;
- (IBAction)btnMenuTapped:(id)sender;
#end
and my .h file
#implementation MainViewController
#synthesize speedCount;
#synthesize speedView;
#synthesize popoverController;
#synthesize locationManager;
- (void)locationError:(NSError *)error {
speedView.text = [error description];
}
-(void)viewWillAppear:(BOOL)animated
{
[userMap setRegion:MKCoordinateRegionMakeWithDistance(userMap.userLocation.coordinate, 5, 5) animated:YES];
}
- (void)viewDidLoad
{
[super viewDidLoad];
appDelegate = [[UIApplication sharedApplication] delegate];
locationManager =[[CLLocationManager alloc] init];
// Do any additional setup after loading the view, typically from a nib.
[userMap setCenterCoordinate: userMap.userLocation.coordinate animated: YES];
[self performSelector:#selector(checkForLogin) withObject:nil afterDelay:1];
[self startLocationServices];
// create LM
self.locationManager = [CLLocationManager new];
// set its delegate
[self.locationManager setDelegate:self];
// set configuration
[self.locationManager setDesiredAccuracy:kCLLocationAccuracyBest];
[self.locationManager setDistanceFilter:kCLDistanceFilterNone];
// start location services
[self.locationManager startUpdatingLocation];
// create an oldLocation variable if one doesn't exist
}
- (void)startLocationServices
{
// create the Location Manager
if (self.locationManager == nil) {
self.locationManager = [CLLocationManager new];
}
// stop services
[self.locationManager stopUpdatingLocation];
[self.locationManager setDelegate:nil];
self.speedView.text = #"Location Services stopped.";
}
// locationManager didUpdateToLocation FromLocation
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
NSLog(#"%#", newLocation);
self.speedView.text = [NSString stringWithFormat:#"%d %.f ", speedCount, [newLocation speed]];
}
+ (NSString *) speedToMPH: (float) value
{
NSString *speedCount = #"0.0 ";
if (value>0) {
float mile = 1609.344f;
float mph = value / mile * 3600;
speedCount = [NSString stringWithFormat: #"%.f ", mph];
}
return speedCount;
}

Answer 1

CLLocation returns the speed in meters per second. So you will have to convert it to miles per hour by multiplying the value with 2.23694.
self.speedView.text = [NSString stringWithFormat:#"%d %.f ", speedCount, [newLocation speed] * 2.23694];