Kontakt信标和iOS：didStartMonitoringForRegion无法按预期工作

Question

I'm starting to work with Kontakt.io beacons on iOS, but even when I've followed the instructions on https://developer.kontakt.io/ios-sdk/quickstart/detecting-beacons/ and the first steps described on https://developer.kontakt.io/ios-sdk/quickstart/installation/ , seems that I can only make it works once.

Here's my ViewController's code:

#import "ViewController.h"
#import <KontaktSDK/KontaktSDK.h>

@interface ViewController () <KTKBeaconManagerDelegate>

@property KTKBeaconManager *beaconManager;
@property KTKBeaconRegion *region1;

@end

@implementation ViewController


- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.beaconManager = [[KTKBeaconManager alloc] initWithDelegate:self];
    NSUUID *myProximityUUID = [[NSUUID alloc] initWithUUIDString:@"xxxxxxxxx...xxxx"];
    _region1 = [[KTKBeaconRegion alloc] initWithProximityUUID:myProximityUUID identifier:@"Beacon_1"];

    switch ([KTKBeaconManager locationAuthorizationStatus]) {
        case kCLAuthorizationStatusNotDetermined:
            [self.beaconManager requestLocationAlwaysAuthorization];
            break;

        case kCLAuthorizationStatusDenied:
        case kCLAuthorizationStatusRestricted:
            // No access to Location Services
            break;

        case kCLAuthorizationStatusAuthorizedWhenInUse:
            // For most iBeacon-based app this type of
            // permission is not adequate
            break;

        case kCLAuthorizationStatusAuthorizedAlways:
            // We will use this later
            if ([KTKBeaconManager isMonitoringAvailable]) {
                [self.beaconManager startMonitoringForRegion:_region1];
            }
            break;
    }
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (void)beaconManager:(KTKBeaconManager *)manager didChangeLocationAuthorizationStatus:(CLAuthorizationStatus)status {
    if (status == kCLAuthorizationStatusAuthorizedAlways) {
        _TheLabel.text = @"YEAH";
        if ([KTKBeaconManager isMonitoringAvailable]) {
            _TheLabel.text = @"YEAH!!!";
            [self.beaconManager startMonitoringForRegion:_region1];
        }
        // When status changes to kCLAuthorizationStatusAuthorizedAlways
        // e.g. after calling [self.beaconManager requestLocationAlwaysAuthorization]
        // we can start region monitoring from here
    }
}

//
- (void)beaconManager:(KTKBeaconManager *)manager didStartMonitoringForRegion:(__kindof KTKBeaconRegion *)region {
    // Do something when monitoring for a particular
    // region is successfully initiated
    _MonitoringStatus.text = @"Success";
    [manager startRangingBeaconsInRegion:region];
}

- (void)beaconManager:(KTKBeaconManager *)manager monitoringDidFailForRegion:(__kindof KTKBeaconRegion *)region withError:(NSError *)error {
    // Handle monitoring failing to start for your region
    _MonitoringStatus.text = @"FAIL!";
}

- (void)beaconManager:(KTKBeaconManager *)manager didEnterRegion:(__kindof KTKBeaconRegion *)region {
    // Decide what to do when a user enters a range of your region; usually used
    // for triggering a local notification and/or starting a beacon ranging
    [manager startRangingBeaconsInRegion:region];
    _OnRegionStatus.text = @"We're in!";
}

- (void)beaconManager:(KTKBeaconManager *)manager didExitRegion:(__kindof KTKBeaconRegion *)region {
    // Decide what to do when a user exits a range of your region; usually used
    // for triggering a local notification and stoping a beacon ranging
    [manager stopRangingBeaconsInRegion:region];
    _OnRegionStatus.text = @"We're out";
}

- (void)beaconManager:(KTKBeaconManager *)manager didRangeBeacons:(NSArray<CLBeacon *> *)beacons inRegion:(__kindof KTKBeaconRegion *)region {
    for(CLBeacon *beacon in beacons){
        _TheLabel.text = [NSString stringWithFormat:@"WOW! %ld", (long)[beacon proximity]];
    }
}

@end

Playing with breakpoints, seems that the didChangeLocationAuthorizationStatus is always being launched (I can see the "YEAH!!!" message on screen every time) but the didStartMonitoringForRegion is not launched unless I uninstall and reinstall (killing app is not working). It does range beacons fine that first time installed, by the way. As you can see, I've tried just ranging beacons without checking the onEnterRegion, but it didn't work.

EDIT: Updated the viewDidLoad with:

case kCLAuthorizationStatusAuthorizedAlways:
            // We will use this later
            if ([KTKBeaconManager isMonitoringAvailable]) {
                if([[self.beaconManager monitoredRegions] count] == 0) [self.beaconManager startMonitoringForRegion:_region1];
                else for(KTKBeaconRegion *reg in [self.beaconManager monitoredRegions]){
                    [self.beaconManager startRangingBeaconsInRegion:reg];
                }
            }
            break;

And this time is working as expected. But I'm a bit confused about this behaviour. The app keeps the region monitorized, even when it was forcefully closed? Thanks in advance!

Answer 1

As far as I know, Kontakt.io's SDK is based on Apple's Core Location, so the following also applies:

In iOS, regions associated with your app are tracked at all times, including when the app isn't running. - source