权限

要使用iBeacon监控，要先做以下检查

检查设备是否支持Beacon扫描

if ([CLLocationManager isMonitoringAvailableForClass:[CLBeaconRegion class]]) {
}

必须获取Always定位权限

if ([CLLocationManager authorizationStatus] != kCLAuthorizationStatusAuthorizedAlways) {
    [CLLocationManager requestAlwaysAuthorization];
}

且必须打开后台获取地理位置更新权限

Important
Apps must have always authorization to use region monitoring, and they must be configured with the Location updates background mode to be launched.

Beacon属性

proximityUUID （The unique ID of the beacons being targeted.）
major （The value identifying a group of beacons.）
minor （The value identifying a specific beacon within a group.）

实现

一般先检测Beacon的进出（Enter/Exit)，再获取具体距离（Ranging)，且苹果建议只在Foreground情况下Ranging

CLBeaconRegion* region = [[CLBeaconRegion alloc] initWithProximityUUID:uuid identifier:uuidStr];
region.notifyEntryStateOnDisplay = YES;
[locationManager startMonitoringForRegion:region];

// CLLocationManagerDelegate
- (void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region {
    [manager startRangingBeaconsInRegion:(CLBeaconRegion *)region];
}

- (void)locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region {
    [manager stopRangingBeaconsInRegion:(CLBeaconRegion *)region];
}

- (void)locationManager:(CLLocationManager *)manager didRangeBeacons:(NSArray *)beacons inRegion:(CLBeaconRegion *)region
{
}