Why is the protocol function not being called

Question

I have a file that implements the protocol and another file that calls the

 //
//  DeviceBLE.swift
//

import Foundation
import CoreBlueTooth
import QuartzCore
import UIKit

class DeviceBLE: NSObject, CBCentralManagerDelegate, CBPeripheralDelegate {

    var centralManager : CBCentralManager!

    init() {
        super.init()
        centralManager = CBCentralManager(delegate: self, queue: nil)
    }

    func centralManagerDidUpdateState(central: CBCentralManager!){
        // Determine the state of the peripheral
        if (central.state == .PoweredOff) {
            println("CoreBluetooth BLE hardware is powered off")
        }
        else if (central.state == .PoweredOn) {
            println("CoreBluetooth BLE hardware is powered on and ready")
            //            connectPeripheral(_ peripheral: CBPeripheral!,
            //                options options: [NSObject : AnyObject]!)
        }
        else if (central.state == .Unauthorized) {
            println("CoreBluetooth BLE state is unauthorized")
        }
        else if (central.state == .Unknown) {
            println("CoreBluetooth BLE state is unknown")
        }
        else if (central.state == .Unsupported) {
            println("CoreBluetooth BLE hardware is unsupported on this platform")
        }
    }
}

this is the file calling

//  ViewController.swift
//  BleTest
import Foundation
import CoreBlueTooth
import QuartzCore
import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        var myBle = DeviceBLE()
     }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

the problem is that centralManagerDidUpdateState never gets called when DeviceBle gets instantiated. I do not understand what I am doing wrong. Could anyone help?

Answer 1

It could be that you are setting myBle to a local variable so by the end of that the viewDidLoad method's execution, DeviceBLE is deallocated. Try making myBle an instance variable of the ViewController class.

class ViewController: UIViewController {
    var myBle: CBCentralManager?

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        self.myBle = DeviceBLE()
      }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
}

Also, in your delegate method. It'd be better practice to use a switch statement instead of several if statements.