Repeat Calls to geolocation Singleton class from multiple views in iOS app

Question

After reading some recommendations on stack overflow and some other articles I have implemented a singleton class that allows me to call a method to update a user's current location. To avoid continuous update of the location information, I added a StopUpdatingPosition call. This works fine for the first time, however following calls fail.

I believe this is because of the way the geolocation stuff is initiated in the examples provided where it checks to see if the singleton is already in place(?)

If a singleton is initialised does it remain in memory? On subsequent calls can I check to see if this is the case and just request it to start updating position?

Here is what I have tried so far.

- (id)init {
    self = [super init];

    if(self) {
        self.locationManager = [CLLocationManager new];
        [self.locationManager setDelegate:self];
        [self.locationManager setDistanceFilter:kCLDistanceFilterNone];
        [self.locationManager setHeadingFilter:kCLHeadingFilterNone];
        [self.locationManager startUpdatingLocation];
        geocoder = [[CLGeocoder alloc] init];
    }

    return self;
}

+ (LocationFunction*)sharedSingleton {
    static LocationFunction* sharedSingleton;
    if(!sharedSingleton) {
        @synchronized(sharedSingleton) {
            sharedSingleton = [LocationFunction new];
        }
    }

    return sharedSingleton;
}

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

    if (currentLocation != nil) {
        myLat = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.latitude];
        myLong = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.longitude];
    }

    // Store the Long & Lat to global variables here
    NSLog(@"Resolving the Address");


        } else {
    // Handle location lookup fail here
        }
    } ];
    [manager stopUpdatingLocation];
    }

I am looking for a way of calling method in an external class from different view controllers. This method obtains the user's current position (Long & Lat), records the info in a global variable, stops any requests to update location method and notifies the view controller when it is done.

Pointers appreciated.

What examples are you talking about at different places in the post. Care to give the links ? — Andy897, Jul 30 '14 at 07:27
The delegate method that you are using is deprecated - refer to CLLocationManagerDelegate reference. I would remove the calls to start/stop updating location and provide instance methods on your singleton class that do this. You can then call these as required. The singleton will remain in memory as it holds a reference to itself. — Paulw11, Jul 30 '14 at 08:09
@Paulw11 Thanks. I'll take a look at what you're suggesting. — Taylermade, Jul 30 '14 at 16:35

score 0 · Answer 1 · edited May 23 '17 at 11:57

0

Another stackoverflow question has an answer that provides a solution. Note however that the call is not correct (I am unable to comment on the answer - too new to stackoverflow!). It should reference "sharedManager" :

- (void)viewDidLoad
{
    [super viewDidLoad];
    [[MyClass sharedManager] startCapture];
}

Hope this helps anyone searching.

edited May 23 '17 at 11:57

Community

1
1

answered Aug 01 '14 at 07:15

Taylermade

11
3

Repeat Calls to geolocation Singleton class from multiple views in iOS app

1 Answers1