在Swift中开始BLE扫描

Question

当我附加到UUID时，我正在扫描一个在我的Swift应用中工作的IBAction: UIButton。但是，我现在正试图让它在应用程序启动时立即开始扫描（后台扫描也应该正常工作，因为我将它设置为单个UUID）。

我已经尝试过我认为合乎逻辑的事情：

self.centralManager?.scanForPeripheralsWithServices(arrayOfServices, options: nil)

viewDidLoad中的

当然arrayOfServices为UUID。但这似乎不起作用。

如何让我的应用程序在启动时查找外围设备而不会按下按钮提示？

Answer 1

您需要初始化CentralManager并等待通过CBCentralManagerDelegate调用centralManagerDidUpdateState。确认状态为PoweredOn后，即可开始扫描。

func centralManagerDidUpdateState(central: CBCentralManager) {

    switch central.state
    {
    case CBCentralManagerState.PoweredOff:
        print("Powered Off")
    case CBCentralManagerState.PoweredOn:
        print("Powered On")
        //Start Scanning Here
         self.centralManager?.scanForPeripheralsWithServices(arrayOfServices, options: nil)
    case CBCentralManagerState.Unsupported,
         CBCentralManagerState.Resetting,
         CBCentralManagerState.Unauthorized,
         CBCentralManagerState.Unknown:
        print("Unexpected CBCentralManager State")
        fallthrough
    default:
        break;
    }
}

Answer 2

Swift 3

func centralManagerDidUpdateState(_ central: CBCentralManager){

    switch central.state{

    case .poweredOn:
        print("Power On")
        central.scanForPeripherals(withServices: nil, options: nil)     
        break

    case .poweredOff:
        print("Power Off")

        break

    case .unsupported:
        print("Power Unsupported")
        break

    case .resetting:
        print("Power Resetting")
        break

    case .unauthorized:
        print("Power Unauthorized")
        break

    case .unknown:
        print("Power Unknown")
        break
    }
}