Thread 1 : signal SIGABRT unrecognized selector - ios

Question

I am currently creating a Bluetooth chat application with Xcode 8 that allows two devices to connect to each other via Bluetooth and send and receive messages to one another. Below is the code for this.
import UIKit
import CoreBluetooth
class ViewController: UIViewController, CBPeripheralManagerDelegate, CBCentralManagerDelegate, CBPeripheralDelegate {
let messageUUID = CBUUID(string: "053D6600-821E-46A7-AC25-43A81D948E8B")
let inputUUID = CBUUID(string: "49A79D26-5323-4374-81EA-29B099AF85C8")
let otherUUID = CBUUID(string: "053D6600-821E-46A7-AC25-43A81D948E87")
var peripheralManager: CBPeripheralManager!
var characteritic: CBMutableCharacteristic!
var getDataPeripheralCharacteristic: CBMutableCharacteristic!
var service: CBMutableService!
var outputData:String = ""
var centralManager: CBCentralManager!
var connectingPeripheral: CBPeripheral?
var centralWriteCharacteristic: CBCharacteristic!
#IBOutlet weak var inputLabel: UITextField!
#IBOutlet weak var outputLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
}
#IBAction func centralMode(sender: AnyObject) {
centralManager = CBCentralManager(delegate: self, queue: nil)
peripheralManager = nil
}
#IBAction func peripheralMode(sender: AnyObject) {
peripheralManager = CBPeripheralManager(delegate: self, queue: nil)
centralManager = nil
}
func peripheralManager(peripheral: CBPeripheralManager, didAddService service: CBService, error: NSError?) {
peripheral.stopAdvertising()
let identifier = Bundle.main.bundleIdentifier!
let manufacturerData = identifier.data(using: String.Encoding.utf8, allowLossyConversion: false)
let dataToBeAdvertised:[String: Any] = [
CBAdvertisementDataLocalNameKey : "Sample peripheral",
CBAdvertisementDataManufacturerDataKey : manufacturerData as Any,
CBAdvertisementDataServiceUUIDsKey : [messageUUID, inputUUID],
]
peripheralManager.startAdvertising(dataToBeAdvertised)
}
#IBAction func sendData(_ sender: UIButton) {
if (peripheralManager != nil) {
let passed = peripheralManager.updateValue(inputLabel.text!.data(using: String.Encoding.utf8)!, for: characteritic!, onSubscribedCentrals: nil)
if passed == false {
print("error couldn't send data")
}
}
if (centralManager != nil) {
if (connectingPeripheral != nil) {
connectingPeripheral?.writeValue(inputLabel.text!.data(using: String.Encoding.utf8)!, for: centralWriteCharacteristic, type: CBCharacteristicWriteType.withResponse)
}
}
}
func peripheralManagerDidUpdateState(_ peripheral: CBPeripheralManager) {
if (peripheral.state == .poweredOn) {
characteritic = CBMutableCharacteristic(type: messageUUID, properties: CBCharacteristicProperties.notify, value: nil, permissions: CBAttributePermissions.readable)
getDataPeripheralCharacteristic = CBMutableCharacteristic(type: inputUUID, properties:
CBCharacteristicProperties.write, value: nil, permissions: CBAttributePermissions.writeable)
service = CBMutableService(type: otherUUID, primary: true)
service.characteristics = [characteritic!, getDataPeripheralCharacteristic!]
peripheralManager!.add(service)
}
}
func peripheralManager(peripheral: CBPeripheralManager, didReceiveWriteRequests requests: [CBATTRequest]) {
for request in requests {
if (request.characteristic.uuid.uuidString == inputUUID.uuidString) {
outputData = String(data: request.value!, encoding: String.Encoding.utf8)!
outputLabel.text = outputData
}
}
}
func peripheralManager(peripheral: CBPeripheralManager, didReceiveReadRequest request: CBATTRequest) {
}
func centralManagerDidUpdateState(_ central: CBCentralManager) {
if central.state == .poweredOn {
centralManager.scanForPeripherals(withServices: nil, options: nil)
//search for peripheral device
}
}
//when peripheral is discovered, this method is called
private func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber) {
self.centralManager.stopScan();
self.connectingPeripheral = peripheral;
peripheral.delegate = self;
centralManager.connect(peripheral, options: nil)
}
//if connection request from central is succesfull, this method is called
func centralManager(central: CBCentralManager, didConnectPeripheral peripheral: CBPeripheral) {
peripheral.delegate = self;
peripheral.discoverServices(nil)
}
//if central discovers services, this method is called
private func peripheral(peripheral: CBPeripheral, didDiscoverServices error: NSError?) {
for service: CBService in peripheral.services! {
peripheral.discoverCharacteristics(nil, for: service)
}
}
private func peripheral(peripheral: CBPeripheral, didDiscoverCharacteristicsForService service: CBService, error: NSError?) {
if (service.uuid.uuidString == otherUUID.uuidString) {
guard let characteristics = service.characteristics else {
return
}
for characteristic in characteristics {
if characteristic.uuid.uuidString == messageUUID.uuidString {
peripheral.setNotifyValue(true, for: characteristic)
} else if characteristic.uuid.uuidString == inputUUID.uuidString {
centralWriteCharacteristic = characteristic
}
}
}
}
private func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) {
if error != nil {
print("Error reading characteristics");
}
if (characteristic.uuid == messageUUID) {
outputData = String(data: characteristic.value!, encoding: String.Encoding.utf8)!
print(outputData)
outputLabel.text = outputData
}
}
}
The Thread 1 signal SIGABRT error is produced when I click either central mode or peripheral mode but not when I click send data. I have done some research online and the general solution to this error is to check the connections for the buttons and make sure there is only one connection and it is the correct one. I have done this but it still has not fixed the error. Below are images of the connections for these buttons.
central mode button
peripheral mode button