Standard Location based iOS app not waking up after suspended IOS - ios

Question

I am developing a location based app which is supposed to fetch user location always.Im using standard location service. But the problem is that the app after keeping idle for some time in background will not fetch the coordinates even after we move to some other locations. As per apple documentation, when a new location arrives, app should wake up automatically, but that is not happening here. I'm sharing the code and using to fetch location and screenshot of my plist.
class SALocation: NSObject,CLLocationManagerDelegate
{
static let sharedInstance : SALocation = SALocation()
var locationManager : CLLocationManager!
var location : CLLocation!
var address : String!
var latitude : NSString?
var longitude : NSString?
var isAdderssLoaded : Bool = false
var locdictionary : NSMutableDictionary = NSMutableDictionary()
func startLocationManager()
{
if self.locationManager == nil
{
self.locationManager = CLLocationManager()
if CLLocationManager.locationServicesEnabled(){
print("location service enabled")
}
self.locationManager.delegate = self
self.locationManager.requestWhenInUseAuthorization()
self.locationManager.distanceFilter = kCLDistanceFilterNone
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
if ( Float (UIDevice.currentDevice().systemVersion) >= 9) {
if #available(iOS 9.0, *) {
self.locationManager.allowsBackgroundLocationUpdates = true
} else {
// Fallback on earlier versions
};
}
self.locationManager.startUpdatingLocation()
//self.locationManager.stopMonitoringSignificantLocationChanges()
}
else
{
self.locationManager.startUpdatingLocation()
}
}
// MARK: CLLocationManagerDelegate
func locationManager(manager: CLLocationManager, didFailWithError error: NSError)
{
UIAlertView(title:"Alert", message:error.description, delegate: nil, cancelButtonTitle:nil, otherButtonTitles:"Ok").show()
}
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation])
{
if locations.count > 0
{
self.location = locations[0]
/* storing date and location to plist
*/
let datenow = NSDate()
let dateformatternow = NSDateFormatter ()
dateformatternow.dateFormat = "yyyyMMdd HH:mm:ss"
let timenow:NSString = dateformatternow.stringFromDate(datenow)
let documetsdirectorypath = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true).last
latitude = NSString(format: "%f",self.location.coordinate.latitude)
longitude = NSString (format: "%f",self.location.coordinate.longitude)
let latlong : NSString = NSString(format:"%#~%#",latitude!,longitude!)
NSUserDefaults.standardUserDefaults().setObject(latlong, forKey: "latlong")
let aFilePath = NSString(format: "%#/location.plist",documetsdirectorypath!)
locdictionary.setObject(latlong, forKey: timenow as String)
locdictionary.writeToFile(aFilePath as String, atomically: true)
///////////// ||storing date and location to plist code ends here||\\\\\\
// self.getAddressFromLocation(locations[0] )
// if (NSUserDefaults.standardUserDefaults().objectForKey(SettingAppRefresh) != nil)
// {
// if (NSUserDefaults.standardUserDefaults().objectForKey(SettingAppRefresh) as! NSString).isEqualToString(FalseString)
// {
// // self.locationManager.stopUpdatingLocation()
// }
// }
}
}
}
What i'm doing here is just get location and write it to a plist file. This works in foreground, background etc fine. But when i keep the app idle for 20 minutes, location is not fetched even if i move to some other locations as the app is suspended
Capabilities tab looks like this

Answer 1

To start location in background you must start background service from the following path
Click on your name -> Click on your app name (target) -> goto capabilities -> find the background mode -> enable the location update mode
I am not sure you started that or not because you not put any screenshot about this.
And also check that your user started background refresh in settings.refer below link for this.
Background App Refresh checking, enabling and disabling programatically for whole device and for each particular application in iOS 7
Update::
For location update in background used below link(objective c)
http://www.creativeworkline.com/2014/12/core-location-manager-ios-8-fetching-location-background/

Answer 2

Well, I don't know how you're getting location updates - significant-location change as example and how you exit from background.
I suggest checking if your app is truly in background mode - UIApplication.sharedApplication().applicationState as it can be terminated.
And I also suggest checking out Apple's Execution States for Apps. - especially for your possible use case Implementing Long-Running Tasks part. There is also a good tutorial at rayywenderlich.com called Background modes.

Answer 3

Please use
self.locationManager.requestAlwaysAuthorization()
and don't forget to update your Info.plist to define the NSLocationAlwaysUsageDescription key.