swift：通过单击按钮与蓝牙设备配对

Question

到目前为止，当应用程序打开时 iPhone 已与蓝牙设备配对，但我想通过单击按钮来配对。我试图将所有扫描和连接功能放在一个 IBAction 中，但是当我按下按钮时没有任何反应。在 IBAction 之后的第一个函数中，我有一个打印输出来检查它是否甚至进入了函数，但我没有得到打印。我还尝试在 manager.scanForPeripherals 之后延迟，但也没有用。我在这里想念什么？有人知道吗？ 感谢您的回复！这是我的代码（没有延迟）：

var manager: CBCentralManager!
var device: CBPeripheral?
var characteristics: [CBCharacteristic]?
var serviceUUID = "1234"
var char1 = "FFE1"
let deviceName = "HMSoft"
var connected = CBPeripheralState.connected
var disconnected = CBPeripheralState.disconnected

 override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    manager = CBCentralManager(delegate: self, queue: nil)


}


override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.


}
 func centralManagerDidUpdateState(_ central: CBCentralManager) {
    switch central.state {
    case .poweredOn: break
        // manager.scanForPeripherals(withServices: nil, options: nil)
    case .unknown: break

    case .resetting: break

    case .unsupported: break

    case .unauthorized: break

    case .poweredOff:

        break

    }
}


   @IBAction func connectBluetooth(_ sender: Any) {

   manager.scanForPeripherals(withServices: nil, options: nil)

func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {

    if let peripheralName = advertisementData[CBAdvertisementDataLocalNameKey] as? String {

        if peripheralName == self.deviceName {

            // save a reference to the sensor tag
            self.device = peripheral
            self.device!.delegate = self

            // Request a connection to the peripheral

            self.manager.connect(self.device!, options: nil)

            print("Check")
        }
    }
}

func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) {

    peripheral.discoverServices(nil)
}


func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) {

    if error != nil {

        return
    }


    if let services = peripheral.services {
        for service in services {

            if (service.uuid == CBUUID(string: serviceUUID)) {
                peripheral.discoverCharacteristics(nil, for: service)
            }
        }
    }

}


func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) {

    device = peripheral
    characteristics = service.characteristics

}

func centralManager(_ central: CBCentralManager, didFailToConnect peripheral: CBPeripheral, error: Error?) {
    if error != nil {

        return
    }
}

}

Answer 1

当您初始化CBCentralManager 并设置它的delegate 时，委托将开始接收事件。

因此，如果您只想在用户点击按钮后激活 CBCentralManager，而不是在屏幕加载后立即激活，那么您要做的最少工作就是将初始化 manager 的代码从viewDidLoad 按钮操作。

所以：

将manager = CBCentralManager(delegate: self, queue: nil) 从viewDidLoad 移动到@IBAction func connectBluetooth(_ sender: Any)，

从IBAction 中删除对scanForPeripherals 的调用，并且；

在centralManagerDidUpdateState 中取消注释// manager.scanForPeripherals(withServices: nil, options: nil)。

Answer 2

不要将函数func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) 放在按钮内。

试试这个：

@IBAction func connectBluetooth(_ sender: Any) {
   manager = CBCentralManager(delegate: self, queue: nil)
   manager.scanForPeripherals(withServices: nil, options: nil)
}

func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {

    if let peripheralName = advertisementData[CBAdvertisementDataLocalNameKey] as? String {

        if peripheralName == self.deviceName {

            // save a reference to the sensor tag
            self.device = peripheral
            self.device!.delegate = self

            // Request a connection to the peripheral

            self.manager.connect(self.device!, options: nil)

            print("Check")
        }
    }
}

在您进行扫描之前，设备知道 BLE 已开启非常重要。

func centralManagerDidUpdateState(_ central: CBCentralManager) {
        switch (central.state) {
        case .unsupported:
            print("BLE is unsupported")
        case .unauthorized:
            print("BLE is unauthorized")
        case .unknown:
            print("BLE is unknown")
        case .resetting:
            print("BLE is reseting")
        case .poweredOff:
            print("BLE is powered off")
        case .poweredOn:
            print("BLE is powered on")
            //must be called
        }
    }