didRangeBeacons call back always triggered with empty array of beacon - ios

Question

I'm using core location library in iOS for finding beacons, I'm in beacon region and the didRangeBeacons callback is triggering but it is always returning an empty array of beacons.
Please find the attached sample code. I have beacon immediate to iPhone, but still, beacon region state is inside when app opened and immediately it is changed to outside state and we are getting an empty array in didRangeBeacons. I have included both NSLocationWhenInUseUsageDescription. The NSLocationAlwaysUsageDescription keys are in the info.plist. The application has location permission set to "always". I'm using both Estimote and Kontakt beacons. OS version is iOS 11.2.6, Device iPhone 5s, Xcode 9.2.
#import "CoreLocationViewController.h"
#interface CoreLocationViewController ()
{
CLLocationManager *locationManager;
CLBeaconRegion *beacon_region;
}
#end
#implementation CoreLocationViewController
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#"CoreLocationViewController viewDidLoad");
NSUUID *ProximityUUID = [[NSUUID alloc] initWithUUIDString:#"b94f62c8-1af4-11e8-accf-0ed5f89f718b"];
beacon_region = [[CLBeaconRegion alloc] initWithProximityUUID:ProximityUUID identifier:#"abqwercds"];
[beacon_region setNotifyEntryStateOnDisplay:YES];
[beacon_region setNotifyOnExit:YES];
[beacon_region setNotifyOnEntry:YES];
locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
if ([CLLocationManager locationServicesEnabled]){
NSLog(#"Location Services Enabled");
if(IS_OS_8_OR_LATER){
NSLog(#"We are in LocationServicesRequestViewController IS_OS_8_OR_LATER");
NSUInteger code = [CLLocationManager authorizationStatus];
NSLog(#"CLLocationManager authorizationStatus %lu",(unsigned long)code);
if (code == kCLAuthorizationStatusNotDetermined) {
NSLog(#"kCLAuthorizationStatusNotDetermined");
[locationManager requestAlwaysAuthorization];
}
}else{
NSLog(#"We are in LocationServicesRequestViewController IS_OS_8_BELOW");
}
}else{
NSLog(#"authorizationStatus ");
}
}
#pragma mark Location Manager Delegate methods
- (void)locationManager:(CLLocationManager *)manager
didFailWithError:(NSError *)error{
NSLog(#"locationManager Error %#",error);
}
-(void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status{
NSLog(#"Status of location service is %d",status);
if ((status == kCLAuthorizationStatusAuthorizedAlways) || (status == kCLAuthorizationStatusAuthorizedWhenInUse)){
NSLog(#"location service status changed 1");
[locationManager startMonitoringForRegion:beacon_region];
[locationManager requestStateForRegion:beacon_region];
}else{
NSLog(#"location service status changed 2");
}
}
-(void)locationManager:(CLLocationManager *)manager didDetermineState:(CLRegionState)state forRegion:(CLRegion *)region{
NSLog(#"CLLocationManager Beacon Region State Determine ");
switch (state) {
case CLRegionStateUnknown:
{
NSLog(#" CLLocationManager Region state is unknown %#",region);
[locationManager stopMonitoringForRegion:beacon_region];
break;
}
case CLRegionStateInside:
{
NSLog(#" CLLocationManager Region state is In-Side %#",region);
[locationManager startRangingBeaconsInRegion:beacon_region];
}
case CLRegionStateOutside:
{
NSLog(#" CLLocationManager Region state is Out-Side %#",beacon_region);
[locationManager stopMonitoringForRegion:beacon_region];
break;
}
}
}
-(void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region{
NSLog(#" CLLocationManager Enter into Region %#",region);
[locationManager startRangingBeaconsInRegion:beacon_region];
}
- (void)locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region {
NSLog(#"didExitRegion location manager %#",region );
[locationManager stopMonitoringForRegion:beacon_region];
}
-(void)locationManager:(CLLocationManager *)manager didStartMonitoringForRegion:(CLRegion *)region{
NSLog(#"CLLocationManager Beacon Monitoring Started for the region %#",region);
}
-(void)locationManager:(CLLocationManager *)manager monitoringDidFailForRegion:(CLRegion *)region withError:(NSError *)error{
NSLog(#"CLLocationManager Monitoring of beacon region %# is failed, Error %#",region,error);
}
-(void)locationManager:(CLLocationManager *)manager rangingBeaconsDidFailForRegion:(CLBeaconRegion *)region withError:(NSError *)error{
NSLog(#"CLLocationManager ranging of beacon region %# is failed, Error %#",region.proximityUUID,error);
}
-(void)locationManager:(CLLocationManager *)manager didRangeBeacons:(NSArray<CLBeacon *> *)beacons inRegion:(CLBeaconRegion *)region{
NSLog(#"beacons %#",beacons);
}