How can I detect is the Bluetooth of the user's iPhone Off or On?

Question

I am trying to detect is the Bluetooth of the user's iPhone On or Off. If it is Off I want to send a notification to the user to turn it On. So far I have done this:

import CoreBluetooth

  class ViewController: UIViewController, CLLocationManagerDelegate,AVCaptureMetadataOutputObjectsDelegate,CBManager {   

 var myBTManager = CBPeripheralManager(delegate: self, queue: nil, options: nil)

  }

func peripheralManagerDidUpdateState(peripheral: CBPeripheralManager!) {
    print(#function)
    if peripheral.state == CBManagerState.poweredOn {
        print("Broadcasting...")

    //    myBTManager!.startAdvertising(_broadcastBeaconDict)
    } else if peripheral.state == CBManagerState.poweredOff {
        print("Stopped")
        myBTManager!.stopAdvertising()
    } else if peripheral.state == CBManagerState.unsupported {
        print("Unsupported")
    } else if peripheral.state == CBManagerState.unauthorized {
        print("This option is not allowed by your application")
    }
}

But as You can see from the picture, something is wrong.

Would you please help me how to fix this issue, I am new to swift and CoreBluetooth technology. I am also using Reachability for detecting the Wi-Fi connection, so if it also works for Bluetooth, I would prefer to use Reachability then.

Answer 1

1. You should be implementing the protocol CBPeripheralManagerDelegate, so replace CBManager in your class definition line with CBPeripheralManagerDelegate.

2. In Swift 3, the signature of peripheralManagerDidUpdateState is now:

   func peripheralManagerDidUpdateState(_ peripheral: CBPeripheralManager)
   

3. You can't initialize the CBPeripheralManager at class creation time since self is only available after the class has been initialized. Instead, make your property:

   var myBTManager: CBPeripheralManager?
   

   and initialize it in viewDidLoad:

   override func viewDidLoad() {
       ...       
       myBTManager = CBPeripheralManager(delegate: self, queue: nil, options: nil)
       ...
   }