iOS HTTP request while in background

Question

It is possible to make HTTP async requests to PHP server while the app being in background? The app is a location based one, and should gather current location and send the coordinates to server every 5(or other value) minutes. Can I make the http posts to the server even the app is in background? I read lot of thoughts about this, but some of them told that can be done, others that can't be done.

Thanks,

Alex.

First off, never try and collect the location on a fixed times. This will drain the battery. Just start listing to major location changes and if these occur then send the new location to the server. If you need a more accurate location start the GPS when the major location change occurs and stop the GPS when you have the location accurate enough for your requirements. Then send the data to the server. — rckoenes, Aug 08 '12 at 12:40
This is the way I done it, I start the update locations, get the location, stop location update, send the request to server, start again location update after 5 minutes, get location, stop, etc. The question is am I able to send the request if the app is in background mode? Thank you. — Alexandru Circus, Aug 08 '12 at 12:45

score 25 · Accepted Answer · answered Aug 08 '12 at 12:44

25

It can be done but it is unreliable because you ask the OS for time to send something and it can accept or deny your request. This is what I have (stolen from somewhere on SO):

[...] //we get the new location from CLLocationManager somewhere here    
BOOL isInBackground = NO;
if ([UIApplication sharedApplication].applicationState == UIApplicationStateBackground)
{
    isInBackground = YES;
}
if (isInBackground)
{
    [self sendBackgroundLocationToServer:newLocation];
}


- (void) sendBackgroundLocationToServer: (CLLocation *) lc
{
    UIBackgroundTaskIdentifier bgTask = UIBackgroundTaskInvalid;
    bgTask = [[UIApplication sharedApplication]
         beginBackgroundTaskWithExpirationHandler:^{
             [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    }];

    NSMutableDictionary *dictionary = [NSMutableDictionary dictionaryWithCapacity:2];
    [dictionary setObject:[NSNumber numberWithDouble:lc.coordinate.latitude] forKey:@"floLatitude"];
    [dictionary setObject:[NSNumber numberWithDouble:lc.coordinate.longitude] forKey:@"floLongitude"];
    // send to server with a synchronous request


    // AFTER ALL THE UPDATES, close the task
    if (bgTask != UIBackgroundTaskInvalid)
    {
        [[UIApplication sharedApplication] endBackgroundTask:bgTask];
    }
}

answered Aug 08 '12 at 12:44

vakio

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Thank you so much, I declare you the developer of the year:). So, basically, it might work some times and others don't, depends by the OS. – Alexandru Circus Aug 08 '12 at 12:51
can i test it in simulator. – Dilip Manek Jan 10 '13 at 06:26
3

That `isInBackground` is totally unnecessary. – 2rs2ts Mar 14 '14 at 15:08
1

@AlexandruCircus Developer of the year? He wrote that he stole the code from sonewhere in SO... – Mantas Laurinavičius Jan 23 '19 at 14:50
are you waking the app using Silent notification first ? – Digs Jul 29 '19 at 19:20
1

Yes You are like a god to me. Thanks – Paresh. P Jan 03 '20 at 11:43
yes, you're right, it is the perfect solution. – Bkillnest Aug 27 '22 at 12:10

score 4 · Answer 2 · edited May 23 '17 at 12:00

4

These links will help you out...

iphone - Connecting to server in background

edited May 23 '17 at 12:00

Community

1
1

answered Aug 08 '12 at 12:51

alloc_iNit

5,173
2
26
54

Thanks, is what vakio suggested, but without code :d . I think beginBackgroundTaskWithExpirationHandler method will solve my problem. – Alexandru Circus Aug 08 '12 at 12:54

iOS HTTP request while in background

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