Question

我的应用可以在前台连接到BLE设备。但是，当应用程序处于后台时，BLE设备在断开设备后不会再次重新连接。我在info.plist中添加了所需的权限：

<key>UIBackgroundModes</key>
    <array>
        <string>bluetooth-central</string>
        <string>bluetooth-peripheral</string>
    </array>

我在HomeViewController中创建了用于扫描的中央管理器对象：

   let centralManager = CBCentralManager(delegate: self, queue: nil)
   centralManager.delegate = self
   let options  = [CBCentralManagerScanOptionAllowDuplicatesKey : true]
   centralManager.scanForPeripherals(withServices:nil, options: options)

我在后台使用app时尝试使用服务的scanForPeripherals但它不起作用：

 let backgroundScanOptions  = [CBCentralManagerScanOptionSolicitedServiceUUIDsKey : true]
 centralManager.scanForPeripherals(withServices: [customServiceUUIDs], options: backgroundScanOptions)

如何在后台重新连接设备？

Answer 1

swift 4

import UIKit
import CoreBluetooth

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, CBCentralManagerDelegate, CBPeripheralDelegate{

var window: UIWindow?

        //MARK:- all variables...
var bleCentralManager: CBCentralManager!
var selectedPeripheral: CBPeripheral!
let serviceUUIDForBackgroundScanning: [CBUUID] = [CBUUID(string: "07A2715C-3B28-4F7F-8824-BA18255B2344")

func bleCentralManagerfunc(){

    self.bleCentralManager = CBCentralManager(delegate: self, queue: nil)
}

        //MARK:- CBCentralManagerDelegate methods...
func centralManagerDidUpdateState(_ central: CBCentralManager) {

    switch central.state{

        case .poweredOn:    central.scanForPeripherals(withServices: nil, options: nil)

        default: print("Please turn on Bluetooth")
    }
}

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

    if !(self.arrayPeripheralList.contains(peripheral)){

            self.arrayPeripheralList.append(peripheral)
    }
}

func applicationDidEnterBackground(_ application: UIApplication) {

    self.bleCentralManager.scanForPeripherals(withServices: serviceUUIDForBackgroundScanning, options: nil)
}
}

在后台iOS中重新连接BLE设备

1 个答案: