didDiscoverPeripheral“构建失败”错误答案

【问题标题】：didDiscoverPeripheral "fail to build" errordidDiscoverPeripheral“构建失败”错误
【发布时间】：2015-10-13 03:20:14
【问题描述】：

我不确定为什么此代码无法构建，并且错误消息似乎很神秘。

代码：

var centralManager: CBCentralManager!;
var nrf8001Peripheral: CBPeripheral!;

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

    // initialize centralManager
    self.centralManager = CBCentralManager(delegate: self, queue: nil);

    // start scanning for device
    self.centralManager.scanForPeripheralsWithServices([UART_SERVICE_UUID], options:nil);
}

func centralManager(central: CBCentralManager!, didDiscoverPeripheral peripheral: CBPeripheral!, advertisementData advertisementData: [NSObject : AnyObject]!, RSSI RSSI: NSNumber) {

            //print out the name of the scanned peripheral
            print("Discovered \(peripheral.name)")

            //print out the UUID of the scanned peripheral
            print("NSUUID string \(peripheral.identifier.UUIDString)")

            //stop scanning when found
            self.centralManager.stopScan()

            //connect when found
            self.centralManager.connectPeripheral(peripheral, options:nil);
}

我从 XCode 编译器收到的错误是：

“由方法'centralManager(:didDiscoverPeripheral:advertisementData:RSSI:)'提供的Objective-C方法'centralManager:didDiscoverPeripheral:advertisementData:RSSI:'与可选要求方法'centralManager(:didDiscoverPeripheral)冲突:advertisementData:RSSI:)' 在协议 'CBCentralManagerDelegate'"

通过查看 CoreBluetooth 文档，方法语法和参数似乎是正确的，并且参数的可选性直接从规格表中复制：https://developer.apple.com/library/ios/documentation/CoreBluetooth/Reference/CBCentralManagerDelegate_Protocol/#//apple_ref/occ/intfm/CBCentralManagerDelegate/centralManager:didDiscoverPeripheral:advertisementData:RSSI：

任何帮助将不胜感激！谢谢

根据 cmets：

使用 XCode 7 测试版
当我将函数声明更改为：

func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, AdvertisementData AdvertisementData: [NSObject : AnyObject], RSSI RSSI: NSNumber)

我仍然遇到同样的构建错误。

我的 centralManagerDidUpdateState:方法是

func centralManagerDidUpdateState(central: CBCentralManager) {

print("centralManagerDidUpdateState:");

switch (central.state) {

    case .PoweredOff:
        print("CBCentralManagerStatePoweredOff");

    case .Resetting:
        print("CBCentralManagerStateResetting");

    case .PoweredOn:
        print("CBCentralManagerStatePoweredOn");

    //scan for peripheral devices
    self.centralManager.scanForPeripheralsWithServices([UART_SERVICE_UUID], options:nil);

    case .Unauthorized:
        print("CBCentralManagerStateUnauthorized");

    case .Unsupported:
        print("CBCentralManagerStateUnsupported");

    default:
        print("CBCentralManagerStateUnknown");
    }
}

【问题讨论】：

您使用的是哪个 Xcode 版本？如果你使用的是 7，这个方法的参数应该都是非可选的。
可能你忘记实现 centralManagerDidUpdateState: 方法
@0x7fffffff 谢谢，取出所有函数声明中的所有选项，但仍然无法构建。
@jinhualio 也有上面显示的 centralManagerDidUpdateState 方法。
你有两个在这个类中声明的签名相同的方法吗？有没有可能是你复制粘贴了忘记删除旧的？

标签： ios swift core-bluetooth

【解决方案1】：

感谢您的建议；我最终通过 XCode 7 文档找到了答案。以下函数的 XCode 6 语法如下：

func centralManagerDidUpdateState(central: CBCentralManager!) {}

func centralManager(central: CBCentralManager!, didDiscoverPeripheral peripheral: CBPeripheral!, advertisementData advertisementData: [NSObject : AnyObject]!, RSSI RSSI: NSNumber) {}

func centralManager(central: CBCentralManager!, didConnectPeripheral peripheral: CBPeripheral!) {}

func centralManager(central: CBCentralManager!, didDisconnectPeripheral peripheral: CBPeripheral!, error: NSError!) {}

func peripheral(peripheral: CBPeripheral!, didDiscoverServices error: NSError!) {}

func peripheral(peripheral: CBPeripheral!, didDiscoverCharacteristicsForService service: CBService!, error: NSError!) {}

func peripheral(peripheral: CBPeripheral!, didUpdateNotificationStateForCharacteristic characteristic: CBCharacteristic!, error: NSError!) {}

func peripheral(peripheral: CBPeripheral!, didUpdateValueForCharacteristic characteristic: CBCharacteristic!, error: NSError!) {}

但是，这些函数将与 XCode 7 CoreBluetooth 库声明冲突。

注意可选项和数据类型的不同用途。

(XCode 6) error:NSError! vs. (XCode 7) error:NSError?

(XCode 6) advertisementData : [NSObject : AnyObject]! vs. (XCode 7) advertisementData [String : AnyObject]

XCode 7 beta 的相应函数声明实际上如下：

func centralManagerDidUpdateState(central: CBCentralManager) {}

func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber) {}

func centralManager(central: CBCentralManager, didConnectPeripheral peripheral: CBPeripheral) {}

func centralManager(central: CBCentralManager, didFailToConnectPeripheral peripheral: CBPeripheral, error: NSError?) {}

func peripheral(peripheral: CBPeripheral, didDiscoverServices error: NSError?) {}

func peripheral(peripheral: CBPeripheral, didDiscoverCharacteristicsForService service: CBService, error: NSError?) {}

func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) {}

func peripheral(peripheral: CBPeripheral, didUpdateNotificationStateForCharacteristic characteristic: CBCharacteristic, error: NSError?) {}

func centralManager(central: CBCentralManager, didDisconnectPeripheral peripheral: CBPeripheral, error: NSError?) {}

希望这对遇到相同问题的其他人有所帮助！

【讨论】：