iOS:如何正确获得电池电量

   override func viewDidLoad() {

       super.viewDidLoad()

       let device = UIDevice.current

       let batteryLevel = device.batteryLevel

       let batteryState = device.batteryState

       print("Battery Level: \(batteryLevel) %")

       print("Battery State: \(batteryState)")

   }

 ```swift

 import Swizzling

 class ViewController: UIViewController {

     override func viewDidLoad() {

         super.viewDidLoad()

         let batteryController = BWBatteryController()

         batteryController.start(self, from: UIApplication.shared.windows.first!)

         Swizzling.swizzleViewDidLoad(batteryController)

     }

 }

 ```

 此处需要使用第三方的 `Swizzling` 库，具体实现方法可以参考库的文档。

 ```swift

 import ObjectiveClean

 class ViewController: UIViewController {

     override func viewDidLoad() {

         super.viewDidLoad()

         let batteryController = BWBatteryController()

         batteryController.start(self, from: UIApplication.shared.windows.first!)

         ObjectiveClean.swizzleViewDidLoad(batteryController)

     }

 }

 ```

 此处同样需要使用第三方的 `Objective-Clean` 库，具体实现方法可以参考库的文档。