obtaining current location in GPS? - iphone

Below is my code but its not working. Can anyone help me???
- (void)viewDidLoad {
[super viewDidLoad];
CLController = [[CoreLocationController alloc] init];
CLController.delegate = self;
//[CLController setDesiredAccuracy:kCLLocationAccuracyBest];
[CLController.locMgr startUpdatingLocation];
}
- (void)locationUpdate:(CLLocation *)location {
locLabel.text = [location description];
}
- (void)locationError:(NSError *)error {
locLabel.text = [error description];
}

You aren't doing the CLocationManager delegate methods properly
(void)locationUpdate:(CLLocation *)location {
locLabel.text = [location description];
}
Should be
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{
locLabel.text = [newLocation description];
}
You should read Apple's documentation http://developer.apple.com/library/ios/#documentation/CoreLocation/Reference/CLLocationManagerDelegate_Protocol/CLLocationManagerDelegate/CLLocationManagerDelegate.html%23//apple_ref/doc/uid/TP40007124 about this thoroughly before implementing it.

Related

Application is hanging when threads are created on location update method

//In view did load...
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.delegate = self;
self.locationManager.distanceFilter = kCLHeadingFilterNone;// kCLHeadingFilterNone;
self.locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
if (newLocation.course >= 0)
{
[NSThread detachNewThreadSelector:#selector(showAlertsIfNeededThread) toTarget:self withObject:nil];
}
}
- (void) showAlertsIfNeededThread
{
#autoreleasepool
{
NSLog(#"Thread started........");
[NSThread sleepForTimeInterval:3.0];
//[self showAlertsIfNeeded];
[self performSelectorOnMainThread:#selector(showAlertsIfNeeded) withObject:nil waitUntilDone:NO];
}
}
After some executions threads are not executing. App is hanging.
Can any one help me out.
Thanks in advance.

CLLocation Manager not updating new location

I am calling CLLocationManager and it's calling its delegate method as well. But my problem is, isn't updating its New Location after traveling 1 km.
Here's my code:
locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationTimer=[NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:#selector(updateLocation1:) userInfo:nil repeats:YES];
locationManager.distanceFilter = kCLDistanceFilterNone;
locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
// Method did update location - Update location when location change
-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
// this method is calling after every 1 sec interval time..
}
-(void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation
{
// this method is not calling once also after travelling around a km ....
}
What am I doing wrong?
You should be calling startUpdatingLocation or startMonitoringSignificantLocationChanges on the location manager for it to start checking for location changes and calling your delegate methods.
locationManager:didUpdateToLocation:fromLocation: is deprecated so you can expect it not to always be used.
If locationManager:didUpdateLocations: is being called then you are receiving location updates.
- (void)viewDidLoad
{
CLLocationManager *locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
locationManager.distanceFilter = kCLLocationAccuracyKilometer;
[locationManager startUpdatingLocation];
CLLocation *location = [locationManager location];
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
}
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
//[manager stopUpdatingLocation];
CLLocationCoordinate2D coordinate_currentlocation = [newLocation coordinate];
float latitude_current = newLocation.coordinate.latitude;
float longitude_current = newLocation.coordinate.longitude;
}
Your first method
- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
// this method is calling after every 1 sec interval time..
}
is used since iOS 6.
The second one is deprecated since iOS 6 and was used prior to iOS 6. You can use both methods, depending on the system version on the device your app is running at, by adding a helper method.
- (void) locationManager:(CLLocationManager *) manager didUpdateToLocation:(CLLocation *) newLocation fromLocation:(CLLocation *) oldLocation
{
[self locationManager:manager helperForLocation:newLocation];
}
- (void) locationManager:(CLLocationManager *) manager didUpdateLocations:(NSArray *) locations
{
if([locations count] > 0)
{
[self locationManager:manager helperForLocation:[locations objectAtIndex:[locations count] - 1]];
}
}
- (void) locationManager:(CLLocationManager *) manager helperForLocation:(CLLocation *) newLocation
{
// your code what to do with location goes here
}
The locations retrieved by iOS 6 are wrapped in a list and could be more than 1. In my example I take the last one and put it to my helper.
i have done this within my app with the use of this
myLocationManager = [[CLLocationManager alloc] init];
myLocationManager.delegate = self;
myLocationManager.desiredAccuracy = kCLLocationAccuracyBest;
[myLocationManager startUpdatingLocation];
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
NSLog(#"didFailWithError: %#", error);
UIAlertView *errorAlert = [[UIAlertView alloc]
initWithTitle:#"Error" message:#"Failed to Get Your Location, Please turn on GPS and Restart The Application"delegate:nil cancelButtonTitle:#"OK" otherButtonTitles:nil];
[errorAlert show];
[errorAlert release];
}
-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
CLLocation *currentLocation = newLocation;
if (currentLocation != nil) {
[NSString stringWithFormat:#"%.8f", currentLocation.coordinate.longitude];
[NSString stringWithFormat:#"%.8f", currentLocation.coordinate.latitude];
}
// Stop Location Manager
[myLocationManager stopUpdatingLocation];
}
-(void)postCurrentLocationOfDevice
{
self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.distanceFilter = kCLDistanceFilterNone;
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[self.locationManager startUpdatingLocation];
self.locationManager.delegate = self;
}
-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
CURRENT_LOCATION = [locations objectAtIndex:0];
[self.locationManager stopUpdatingLocation];
}
-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
CURRENT_LOCATION = newLocation;
[self.locationManager stopUpdatingLocation];
}

Tracing the address in MapKit

My location manager is not updating my coordinates of current locations so that i cant able to trace that address.......
I am using the following code,
- (void)viewDidLoad
{
[super viewDidLoad];
locationManager = [[CLLocationManager alloc] init];
//locationManager.desiredAccuracy = kCLLocationAccuracyBest;
locationManager.delegate = self;
[locationManager startUpdatingLocation];
// startLocation = nil;
[super viewDidLoad];
}
-(void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation
{
NSLog(#"Latitude:%f Longitude:%f", newLocation.coordinate.latitude, newLocation.coordinate.longitude);
geocoder =[[[MKReverseGeocoder alloc] initWithCoordinate:newLocation.coordinate]autorelease];
geocoder.delegate=self;
[geocoder start];
}
-(void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
NSLog(#"%#Error",[error description]);
}
- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark{
NSString *street=[placemark.addressDictionary objectForKey:#"Street"];
NSLog(#"%#",street);
}
It shows the error report
Error Domain=kCLErrorDomain Code=0 "The operation couldnft be completed. (kCLErrorDomain error 0.)"Error
How to overcome this?.

How to update location only when button is pressed

How can I make my application update location only when a button is pressed?
I have a button named "REFRESH". Everytime this button is pressed, I want to show my user their location. For example, 51 Bourke Street, Victoria.
However, I do not want to update my location regularly. I want to update its location only when the button is pressed, to save battery power.
What do you think? Am I doing it correctly?
I have these classes:
VoteViewController.h and VoteViewController.m
CoreLocationController.h and CoreLocationController.m
This is what I have:
VoteViewController.h class
#interface VoteViewController : UIViewController <CoreLocationControllerDelegate>
{
CoreLocationController *coreController;
}
- (void)locationUpdate:(CLLocation *)location;
- (void)locationError:(NSError *)error;
- (void)geoReverseAddress:(MKPlacemark *)placeMark;
- (IBAction)refreshButtonPressed;
VoteViewController.m class
- (void)viewDidLoad
{
[super viewDidLoad];
coreController = [[CoreLocationController alloc] init];
coreController.delegate = self;
}
- (IBAction)refreshButtonPressed
{
NSLog(#"Refresh Button pressed");
label.text = [NSString stringWithString:#""];
[coreController.locationManager startUpdatingLocation];
}
- (void)locationUpdate:(CLLocation *)location
{
comments.text = [location description];
[coreController.locationManager stopUpdatingLocation];
}
- (void)locationError:(NSError *)error
{
comments.text = [error description];
[coreController.locationManager stopUpdatingLocation];
}
- (void)geoReverseAddress:(MKPlacemark *)placeMark
{
label.text = [NSString stringWithFormat:#"%# %#, %#", [placeMark subThoroughfare],
[placeMark thoroughfare], [placeMark locality]];
}
CoreLocationController.h class
#protocol CoreLocationControllerDelegate <NSObject>
#required
- (void)locationUpdate:(CLLocation *)location;
- (void)locationError:(NSError *)error;
- (void)geoReverseAddress:(MKPlacemark *)placeMark;
#end
#interface CoreLocationController : NSObject <CLLocationManagerDelegate, MKReverseGeocoderDelegate>
{
CLLocationManager *locationManager;
id delegate;
MKReverseGeocoder *reverse;
}
#property(nonatomic, retain) CLLocationManager *locationManager;
#property(nonatomic, retain) id delegate;
#end
CoreLocationController.m class
-(id) init
{
self = [super init];
if (self != nil)
{
self.locationManager = [[[CLLocationManager alloc] init] autorelease];
self.locationManager.delegate = self;
self.locationManager.distanceFilter = kCLHeadingFilterNone;
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
}
return self;
}
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
NSLog(#"Update location");
[self.delegate locationUpdate:newLocation];
reverse = [[MKReverseGeocoder alloc] initWithCoordinate:[newLocation coordinate]];
reverse.delegate = self;
[reverse start];
}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
[self.delegate locationError:error];
}
- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFailWithError:(NSError *)error
{
[self.delegate locationError:error];
[reverse cancel];
[reverse release];
}
- (void)reverseGeocoder:(MKReverseGeocoder *)geocoder didFindPlacemark:(MKPlacemark *)placemark
{
[self.delegate geoReverseAddress:placemark];
[reverse cancel];
[reverse release];
}
When you first fire up CLLocationManager, you're very likely to get one stale location from the last time it ran. Once that's out of the way, you're going to start getting very inaccurate locations while the device uses WiFi sniffing and cell triangulation, while the GPS looks for a fix.
So in your didUpdateToLocation method, you probably want to throw away the first hit, and then test the .horizontalAccuracy value of your newLocation object for a low enough value to trust.
Apart from that, I don't see anything bad about what you've sent here. I'm not sure I'd go to the trouble of wrapping the location fetching work in its own class, I'd probably just do that out in my viewController. But that's a style choice. If you're reusing this functionality elsewhere, what you've got here is obviously the way to go.

Method not getting called (Core Location) Cocoa Touch

Hey guys,
I'm trying to call the update method but its not working, any idea?
#import "TrackerViewController.h"
#implementation TrackerViewController
-(IBAction)updateButton:(id)sender{
[self update];
}
-(void)update{
locmanager = [[CLLocationManager alloc] init];
[locmanager setDelegate:self];
[locmanager setDesiredAccuracy:kCLLocationAccuracyBest];
[locmanager startUpdatingLocation];
}
-(void)viewDidLoad {
[self update];
}
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
CLLocationCoordinate2D loc = [newLocation coordinate];
latitude.text = [NSString stringWithFormat: #"%f", loc.latitude];
longtitude.text = [NSString stringWithFormat: #"%f", loc.longitude];
}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
}
The didUpdateToLocation will be called when an location changes.
I guess you are testing it in simulator and on simulator no change occurs in location so the method don't called.
Suggesstion You should implement other delegate methods to check whats happening; in case if there is some error. For example: locationManager:didFailWithError: