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How to make forced update of user location?

开发者 https://www.devze.com 2023-03-29 16:37 出处:网络
I need to get current user location but I don\'t know if it has changed or not. Can I request a forced location update from CLLocationManager? 开发者_开发百科Or is there any other way to do that?Stopp

I need to get current user location but I don't know if it has changed or not. Can I request a forced location update from CLLocationManager? 开发者_开发百科Or is there any other way to do that?


Stopping and restarting the LocationManager should force the device to re-acquire an initial position.

[locationManager stopUpdatingLocation];
[locationmanager startUpdatingLocation];


I have had the same problem in one of my apps. I actually had to change the app structure. This is what I have done: This class has a public method. -(void)locateMe; an abstract class needs to instantiate this class and run the locateMe then when userIsLocated a notification will be broadcasted. and another method can get the result coordinates from (CLLocation *)currentLocation;

#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>

@interface ManageUserLocation : NSOperation <CLLocationManagerDelegate> {
    CLLocationManager       *locationManager;
    CLLocation              *currentLocation;
}
@property (nonatomic, retain) CLLocationManager     *locationManager;
@property (nonatomic, retain) CLLocation            *currentLocation;

-(void) locateMe;
@end

in the .m

    #import "ManageUserLocation.h"

    @implementation ManageUserLocation

    @synthesize locationManager;
    @synthesize currentLocation; // Other classes use this to get the coordination even better you can make another method that even dont get the direct access to currentLocation. It is up to you. 

    - (id)init
    {
        self = [super init];
        if (self) {
         //[self locateMe]; // Just a hook if you need to run it 
        }
        return self;
    }

    -(void) locateMe {
        self.locationManager = nil;
        self.locationManager = [[CLLocationManager alloc] init];
        self.locationManager.desiredAccuracy=kCLLocationAccuracyBest;
        self.locationManager.delegate = self;
        [self.locationManager startUpdatingLocation];
    }

    - (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation { 
        // User location has been found/updated, load map data now.
        [self.locationManager stopUpdatingLocation];
        currentLocation = [newLocation copy];   
        // WooHoo Tell everyone that you found the userLocation
        [[NSNotificationCenter defaultCenter] postNotificationName:@"userLocationIsFound" object:nil];
    }

    - (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error{
        // Failed to find the user's location. This error occurs when the user declines the location request or has location servives turned off.
        NSString * errorString = @"Unable to determine your current location.";
        UIAlertView * errorAlert = [[UIAlertView alloc] initWithTitle:@"Error Locating" message:errorString delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [errorAlert show];
        [errorAlert release];
        [locationManager stopUpdatingLocation];
    }
    - (void)dealloc { #warning dont forget this :) }
@end

Hope this help.


I think is contrary to Apple Guidelines to force updates. Apple says geo-update will occur automatically, but at un unknown time.

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