CBCentralManager iOS10和iOS9

Question

所以我正在迁移到iOS10,但我还需要我的代码才能在iOS9上运行.我正在使用CoreBluetooth和CBCentralManagerDelegate.我可以让我的代码适用于iOS10但是我需要后备才能适用于iOS9.

func centralManagerDidUpdateState(_ central: CBCentralManager) {
    if #available(iOS 10.0, *) {
        switch central.state{
        case CBManagerState.unauthorized:
            print("This app is not authorised to use Bluetooth low energy")
        case CBManagerState.poweredOff:
            print("Bluetooth is currently powered off.")
        case CBManagerState.poweredOn:
            print("Bluetooth is currently powered on and available to use.")
        default:break
        }
    } else {

        // Fallback on earlier versions
        switch central.state{
        case CBCentralManagerState.unauthorized:
            print("This app is not authorised to use Bluetooth low energy")
        case CBCentralManagerState.poweredOff:
            print("Bluetooth is currently powered off.")
        case CBCentralManagerState.poweredOn:
            print("Bluetooth is currently powered on and available to use.")
        default:break
        }
    }
}

我收到错误:

Enum case 'unauthorized' is not a member of type 'CBManagerState'

在线上:

case CBCentralManagerState.unauthorized: 

以及.poweredOff和.poweredOn.

在这两种情况下我是如何让它工作的任何想法？

Answer 1

您可以简单地省略枚举类型名称,只使用.value.这将在没有警告的情况下编译,并且可以在iOS 10及更早版本上运行,因为底层原始值是兼容的.

func centralManagerDidUpdateState(_ central: CBCentralManager) {
        switch central.state{
        case .unauthorized:
            print("This app is not authorised to use Bluetooth low energy")
        case .poweredOff:
            print("Bluetooth is currently powered off.")
        case .poweredOn:
            print("Bluetooth is currently powered on and available to use.")
        default:break
        }
}

Answer 2

我使用Swift 2.3(针对iOS 8及更高版本)在Xcode 8上解决了这个问题,方法是创建一个CBCentralManager旧的枚举类型的扩展属性CBCentralManagerState.我把它命名了centralManagerState.我指的是CBCentralManager.centralManagerState我曾经指的地方CBCentralManager.state.

extension CBCentralManager {

    internal var centralManagerState: CBCentralManagerState  {
        get {
            return CBCentralManagerState(rawValue: state.rawValue) ?? .Unknown
        }
    }
}

虽然他们还没有发布代码,但我从这个论坛帖子中得到了这个想法.

Answer 3

我就此事联系了苹果公司，并得到了以下答复（释义）。

由于 swift 性质的变化，上述实现是不可能的，但是您可以使用枚举的 rawValue，因为两个类之间的状态是相同的。因此，现在以下内容将起作用：

func centralManagerDidUpdateState(_ central: CBCentralManager) {
    if #available(iOS 10.0, *) {
        switch central.state{
        case CBManagerState.unauthorized:
            print("This app is not authorised to use Bluetooth low energy")
        case CBManagerState.poweredOff:
            print("Bluetooth is currently powered off.")
        case CBManagerState.poweredOn:
            print("Bluetooth is currently powered on and available to use.")
        default:break
        }
    } else {
        // Fallback on earlier versions
        switch central.state.rawValue {
        case 3: // CBCentralManagerState.unauthorized :
            print("This app is not authorised to use Bluetooth low energy")
        case 4: // CBCentralManagerState.poweredOff:
            print("Bluetooth is currently powered off.")
        case 5: //CBCentralManagerState.poweredOn:
            print("Bluetooth is currently powered on and available to use.")
        default:break
        }
    }
}