iOS swift 5: 關於 "CoreBluetooth XPC connection invalid"

CBCentralManager 這個class, 真的很不容易使用,限制滿多的.

解決方案來源:
ShenYun's Memo: iOS CoreBluetooth swift 2 連線客製化藍芽 BLE 模組 - ( 2 ) 連線
swift - CoreBluetooth XPC connection invalid - Stack Overflow


解說
 1: 專案的 Target -> Capabilities -> Background Modes -> 勾選兩個 Bluetooth LE Accessor

 2: info.plist 要加上
<key>NSBluetoothPeripheralUsageDescription</key>
<string>Play with BLE Compatible devices</string>

 3: 把 CBCentralManager 放在一個 Class中

class TBleDeviceConnect: NSObject, CBCentralManagerDelegate, BPeripheralDelegate
{
   var centralManager: CBCentralManager! = nil
   func centralManagerInit()
   {
    centralManager = CBCentralManager.init(delegate: self, queue: nil, options: [CBCentralManagerOptionShowPowerAlertKey: true])
   }
}

 4: 把包含 CBCentralManager Class放到 MainViewController 中
     CBCentralManager一定要在 UIViewController中

class MainViewController: UIViewController
{
   /* Class Bluetooth CBCentralManager Control */
   var BleDeviceConnect: TBleDeviceConnect! = nil
}

 5: 如果是用在其他的 ViewController
    用 prepare for segue 方法將 CBCentralManager傳遞過去
    請參考 iOS swift 5: About Segue Prepare to NavigationController 

 6: 如果是在 Thread Function 中使用

DispatchQueue.main.async
{
 self.BleDeviceConnect.centralManagerInit()  
}

 7: 同一個Class 中的CBCentralManager 只能呼叫一次 centralManager = CBCentralManager.init(...)
   就會發生 "CoreBluetooth XPC connection invalid"
   解決方法還在尋找中....
   所以現在的做法呼叫 scanForPeripherals來重新掃描 Bluetooth Device