Estimote: didRangeBeacons not called when in background? - objective-c

Question

i was wondering why I don't get the notification if my beacon proximity is Immediate – when the app is in background. In foreground mode, everything works fine.
#import "ESTViewController.h"
#import <ESTBeaconManager.h>
#interface ESTViewController () <ESTBeaconManagerDelegate>
#property (nonatomic, strong) ESTBeaconManager* beaconManager;
#property (nonatomic, strong) ESTBeacon* selectedBeacon;
#property (weak, nonatomic) IBOutlet UILabel *outputLabel;
#end
#implementation ESTViewController
- (void)viewDidLoad
{
[super viewDidLoad];
/////////////////////////////////////////////////////////////
// setup Estimote beacon manager
// craete manager instance
self.beaconManager = [[ESTBeaconManager alloc] init];
self.beaconManager.delegate = self;
self.beaconManager.avoidUnknownStateBeacons = YES;
// create sample region with major value defined
ESTBeaconRegion* region = [[ESTBeaconRegion alloc] initWithProximityUUID:ESTIMOTE_PROXIMITY_UUID identifier: #"EstimoteSampleRegion" ];
NSLog(#"TODO: Update the ESTBeaconRegion with your major / minor number and enable background app refresh in the Settings on your device for the NotificationDemo to work correctly.");
// start looking for estimote beacons in region
[self.beaconManager startMonitoringForRegion:region];
[self.beaconManager startRangingBeaconsInRegion:region];
[self.beaconManager requestStateForRegion:region];
// setup view
self.outputLabel.text = #"Seachring for reagion";
}
-(void)beaconManager:(ESTBeaconManager *)manager
didDetermineState:(CLRegionState)state
forRegion:(ESTBeaconRegion *)region
{
// NSLog(#"Region: %#", region);
if(state == CLRegionStateInside)
{
NSLog(#"State: CLRegionStateInside");
}
else
{
NSLog(#"State: CLRegionOutside");
}
}
-(void)beaconManager:(ESTBeaconManager *)manager
didRangeBeacons:(NSArray *)beacons
inRegion:(ESTBeaconRegion *)region
{
if([beacons count] > 0)
{
self.selectedBeacon = [beacons firstObject]; // get the closest
NSString* labelText = [NSString stringWithFormat:
#"Major: %i, Minor: %i\nRegion: ",
[self.selectedBeacon.major unsignedShortValue],
[self.selectedBeacon.minor unsignedShortValue]];
// calculate and set new y position
switch (self.selectedBeacon.proximity)
{
case CLProximityUnknown:
labelText = [labelText stringByAppendingString: #"Unknown"];
break;
case CLProximityImmediate:
labelText = [labelText stringByAppendingString: #"Immediate"];
[self fireNotification];
break;
case CLProximityNear:
labelText = [labelText stringByAppendingString: #"Near"];
break;
case CLProximityFar:
labelText = [labelText stringByAppendingString: #"Far"];
break;
default:
break;
}
self.outputLabel.text = labelText;
}
}
-(void)fireNotification {
NSLog(#"Fire Notification from background");
// present local notification
UILocalNotification *notification = [[UILocalNotification alloc] init];
notification.alertBody = #"You are very close to the beacon";
notification.soundName = UILocalNotificationDefaultSoundName;
[[UIApplication sharedApplication] presentLocalNotificationNow:notification];
// Request a server...
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end

Answer 1

With iOS, ranging for iBeacons generally only works in the foreground. The code that checks for CLProximityImmediate is in a ranging callback method.
If your app is in the background, it will only receive ranging callbacks for five seconds after entering/exiting a monitored iBeacon region.
This principle is true for the standard iOS CoreLocation APIs. While you are using the proprietary Estimote SDK, the same limitations also apply since it is a wrapper around the standard APIs.