iOS Can not find the iBeacon again in fore ground - ios

Question

Hi~ I'm learning to use CLLocationManager to detect iBeacon. I read this article:
http://developer.radiusnetworks.com/2013/11/13/ibeacon-monitoring-in-the-background-and-foreground.html
It says that startRangingBeaconsInRegion will make system scan beacon every second. I test and it's right.
But a problem happens if the program only execute startMonitoringForRegion without startRangingBeaconsInRegion.
My program can find the beacon first time I start a beacon hardware, and after I stop beacon the founction didExitRegion is called. But after I start the beacon second time, program cannot find it(execute didEnterRegion) at all. I have wait for 1 hour.
The Hardware I use for test are iPhone 5s with iOS 8.1.2 and radBeacon USB.
Here is my code.
#import "ViewController.h"
#import <CoreLocation/CoreLocation.h>
#interface ViewController () <CLLocationManagerDelegate>
#property (retain, nonatomic) IBOutlet UITextView *textView;
#property (strong, nonatomic) NSMutableString *myLog;
#property (strong, nonatomic) CLLocationManager *locationManager;
#property (strong, nonatomic) CLBeaconRegion *beaconRegion;
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[self startBeaconMonitoring];
}
- (void)startBeaconMonitoring {
_locationManager = [[CLLocationManager alloc] init];
_locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters;
_locationManager.delegate = self;
[_locationManager performSelector:#selector(requestAlwaysAuthorization)];
[self userGeofencingPreferencesWereUpdatedWithNotification:nil];
[self updateLogWithString:#"start the app"];
}
- (void) userGeofencingPreferencesWereUpdatedWithNotification: (NSNotification *) notification
{
if (1) {
NSUUID *proximityUUID = [[NSUUID UUID] initWithUUIDString:#"EEF45689-BBE5-4FB6-9E80-41B78F6578E2"];
_beaconRegion = [[CLBeaconRegion alloc]
initWithProximityUUID:proximityUUID
identifier:#"1"];
_beaconRegion.notifyEntryStateOnDisplay = YES;
[_locationManager startMonitoringForRegion:_beaconRegion];
//[_locationManager startRangingBeaconsInRegion:beaconRegion];
//[_locationManager stopUpdatingLocation];
}
}
- (void) locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region
{
[self updateLogWithString:#"enter"];
NSLog(#"enter");
}
- (void) locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region
{
[self updateLogWithString:#"exit"];
NSLog(#"exit");
}
- (void)locationManager:(CLLocationManager *)manager
didRangeBeacons:(NSArray *)beacons
inRegion:(CLBeaconRegion *)region {
//NSLog(#"range");
}
- (void)dealloc {
[_textView release];
[_myLog release];
[_locationManager release];
[_beaconRegion release];
[super dealloc];
}
- (NSMutableString *)myLog {
if (!_myLog) {
_myLog = [[NSMutableString alloc] init];
}
return _myLog;
}
- (void) updateLogWithString:(NSString*)newLog {
NSDate *now = [NSDate date];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.dateFormat = #"hh:mm:ss";
[dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
NSString * logWithTime = [NSString stringWithFormat:#"%#---%#\n",[dateFormatter stringFromDate:now], newLog];
[self.myLog appendString:logWithTime];
self.textView.text = self.myLog;
[dateFormatter release];
}
#end

Answer 1

I found something by accident and this solve my problem. When I use a iOS APP named Broadcaster to simulate a iBeacon, it triggers iBeacon detection APP very quickly which run on another iOS device no matter in foreground, background or screen off.
When I use Rad Beacon USB, still failure. I test all my 4 Rad Beacon USBs and same thing happens.
It seems that the BLE message sent by Rad Beacon USB is a little different from which simulated by iOS(I just tried the APP Broadcaster). And iOS8 treats them
different in some situations.
My Rad Beacon USBs are version 2.0.