iBeacon：在运行应用程序时，没有调用didRangeBeacons

Question

I prepared all the necessary stuff to setup a beacon region:

// Create a NSUUID with the same UUID as the broadcasting beacon
NSUUID *uuid = [[NSUUID alloc] initWithUUIDString:@"E2C56DB5-DFFB-48D2-B060-D0F5A71096E0"];
//raspberry pi:E2C56DB5-DFFB-48D2-B060-D0F5A71096E0
//estimote:B9407F30-F5F8-466E-AFF9-25556B57FE6D

// Setup a new region with that UUID and same identifier as the broadcasting beacon
self.myBeaconRegion = [[CLBeaconRegion alloc] initWithProximityUUID:uuid
                                                                identifier:@"monaLisaBeacon"];

// Tell location manager to start monitoring for the beacon region
[self.locationManager startMonitoringForRegion:self.myBeaconRegion];

However, didRangeBeacons is not always invoked. It invokes only once but then stops getting invoked.

Answer 1

Are you sure that didRangeBeacons was invoked even once? It will not be invoked if you just call startMonitoringForRegion . When you call startMonitoringForRegion you should get callback in your locationManager's delegate object in the form of didDetermineState , didEnterRegion and didExitRegion . What you need to do is, in your didEnterRegion method, call startRangingBeaconsInRegion . Here is an example:

- (void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region {
    if ([region isKindOfClass:[CLBeaconRegion class]]) {
        CLBeaconRegion *beaconRegion = (CLBeaconRegion *)region;

        //now start ranging
        [_locationManager startRangingBeaconsInRegion:beaconRegion];
    }
}

Also dont forget to stop ranging:

- (void)locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region {
    if ([region isKindOfClass:[CLBeaconRegion class]]) {
        CLBeaconRegion *beaconRegion = (CLBeaconRegion *)region;

        //STOP ranging
        [_locationManager stopRangingBeaconsInRegion:beaconRegion];
    }
}

Only if you start ranging, your didRangeBeacons will be invoked.

Hope this helps.

Answer 2

Try following code:

// Create a NSUUID with the same UUID as the broadcasting beacon
NSUUID *uuid = [[NSUUID alloc] initWithUUIDString:@"E2C56DB5-DFFB-48D2-B060-D0F5A71096E0"];
//raspberry pi:E2C56DB5-DFFB-48D2-B060-D0F5A71096E0
//estimote:B9407F30-F5F8-466E-AFF9-25556B57FE6D

// Setup a new region with that UUID and same identifier as the broadcasting beacon
self.myBeaconRegion = [[CLBeaconRegion alloc] initWithProximityUUID:uuid
                                                                identifier:@"monaLisaBeacon"];

// Tell location manager to start monitoring for the beacon region
[self.locationManager startMonitoringForRegion:self.myBeaconRegion];
[self.locationManager startRangingBeaconsInRegion:beaconRegion];

You need to start ranging beacons as well to make didRangebeacons to be called.

Answer 3

Are you only seeing this with your Raspberry Pi-based beacon? If so, your Pi's advertisements may be getting turned off by another device attempting to connect with it. The Knock app for OSX is known to cause this problem , although other apps may do it, too.

If this is the problem, there is a fix documented in an edit to the blog post telling you how to build an iBeacon out of a Raspberry Pi. You need to edit the iBeacon start script on the Pi to change this line:

sudo hciconfig $BLUETOOTH_DEVICE leadv 0

to:

sudo hciconfig $BLUETOOTH_DEVICE leadv 3

Alternatively, you can try simply shutting off whatever app is running that is trying to establish a Bluetooth LE connection to the Raspberry Pi. If you don't know what app is doing that, though, this may be hard.