位置情報を利用するエンタープライズアプリを構築する – WWDC2020

// 位置情報サービスの可用性変更時の通知を受け取る
// Add NSLocationWhenInUseUsageDescription to your Info.plist 
// e.g. “Location is required for placing orders while using the app."

locationManager.requestWhenInUseAuthorization()

func locationManager(
    _ manager: CLLocationManager,
    didChangeAuthorization status: CLAuthorizationStatus) {
        
    switch status {
    case .restricted, .denied: 
        disableLocationFeatures()

    case .authorizedWhenInUse, .authorizedAlways: 
        enableLocationFeatures()

    case .notDetermined: // The user hasn’t chosen an authorization status
    }
}

// ハードウェアがサービスを利用可能かチェックする

if CLLocationManager.isMonitoringAvailable(for: CLBeaconRegion.self) {
    // Supports region monitoring to detect beacon regions
}

if CLLocationManager.isRangingAvailable() {
    // Supports obtaining the relative distance to a nearby iBeacon device
}

// リージョン監視を行い、ビーコンを検出する実装
// Stage 1: Region Monitoring

func monitorBeacons() {
    if CLLocationManager.isMonitoringAvailable(for: CLBeaconRegion.self) {

        // ビーコンの監視には、proximityUUIDを使用し、CLBeaconIdentityConstraintオブジェクトを作成
        let constraint = CLBeaconIdentityConstraint(uuid: proximityUUID)

        let beaconRegion = CLBeaconRegion(
            beaconIdentityConstraint: constraint,
            identifier: beaconID
        )

        // startMonitoringforメソッドで登録する        
        // https://developer.apple.com/documentation/corelocation/cllocationmanager/1423656-startmonitoring
        self.locationManager.startMonitoring(for: beaconRegion)
    }
}

// Stage 2: Beacon Ranging

// ビーコンが領域内に入った時
func locationManager(_ manager: CLLocationManager, didEnterRegion region: CLRegion) {
    guard let region = region as? CLBeaconRegion,
        CLLocationManager.isRangingAvailable() // このメソッドで距離測定可能かを確認する
        else { return }
    
    let constraint = CLBeaconIdentityConstraint(uuid: region.uuid)
    manager.startRangingBeacons(satisfying: constraint)
    beaconsToRange.append(region)
}

// ビーコンが領域外になった時
func locationManager(_ manager: CLLocationManager, didExitRegion region: CLRegion) {
    
}

func locationManager(
    _ manager: CLLocationManager,
    didRangeBeacons beacons: [CLBeacon],
    in region: CLBeaconRegion) {
    
    guard let nearestBeacon = beacons.first else { return }
    let major = CLBeaconMajorValue(truncating: nearestBeacon.major)
    let minor = CLBeaconMinorValue(truncating: nearestBeacon.major)
    
    switch nearestBeacon.proximity {
    case .near, .immediate:
        displayInformation(for: major, and: minor)
        
    default:
        handleUnknownOrFarBeacon(for: major, and: minor)
    }
}

// Formatting Dates
let dateFormatter = DateFormatter()
dateFormatter.dateStyle = .medium
dateFormatter.timeStyle = .short
dateFormatter.string(from: Date())
// "Jun 25, 2020 at 9:41 AM"


// Configuring the Format of Currency
let formatter = NumberFormatter()
formatter.currencyCode = "CAD"
formatter.numberStyle = .currency
formatter.string(from: amount)
// "CA$1.00"