Check Bluetooth status - Swift 4

问题

I have a problem with the Bluetooth in Xcode. I can’t find a great solution on how to check if Bluetooth is on or not. I want just that. I searched around the web some solution, but nothing works for me. Any idea on how to check Bluetooth? I imported the CoreBluetooth class and I made this line of code:

if CBPeripheralManager.authorizationStatus() == .denied { code }
if CBPeripheralManager.authorizationStatus() == .authorized  { code }

回答1:

Implement CBCentralManagerDelegate delegate for that.

 var manager:CBCentralManager!

 viewDidLoad() {      // Or init()
     manager          = CBCentralManager()
     manager.delegate = self
 }

Delegate method :

func centralManagerDidUpdateState(_ central: CBCentralManager) {
    switch central.state {
    case .poweredOn:
        break
    case .poweredOff:
        print("Bluetooth is Off.")
        break
    case .resetting:
        break
    case .unauthorized:
        break
    case .unsupported:
        break
    case .unknown:
        break
    default:
        break
    }
}

回答2:

you will need to use CBCentralManager and it provide delegate method "centralManagerDidUpdateState" https://developer.apple.com/documentation/corebluetooth/cbcentralmanager

func centralManagerDidUpdateState(_ central: CBCentralManager)
{
    if central.state == .poweredOn
    {
        print("Searching for BLE Devices")

        // Scan for peripherals if BLE is turned on
    }
    else
    {
        // Can have different conditions for all states if needed - print generic message for now, i.e. Bluetooth isn't On
        print("Bluetooth switched off or not initialized")
    }
}

来源：https://stackoverflow.com/questions/47300632/check-bluetooth-status-swift-4