Hello, I am writing an app that connects to an Arduino Nano with BLE. I would like the app to read data sent from the Arduino (the peripheral). My code connects to the Arduino using a specific UUID, but I think it is failing to detect a service from the Arduino. Here is my BluetoothViewController: // // BluetoothViewController.swift import UIKit import CoreBluetooth //local central device object class BluetoothViewController: UIViewController, CBPeripheralDelegate, CBCentralManagerDelegate { //properties private var centralManager: CBCentralManager! private var peripheral: CBPeripheral! var feedbackAmt = String() // from session setup view controller //label to display stage of gait cycle @IBOutlet weak var StateLabel: UILabel! //characteristics private var StateVar: CBCharacteristic? override func viewDidLoad() { super.viewDidLoad() centralManager = CBCentralManager(delegate: self, queue: nil) } //func tells the delegate the central manager's state updated (required) func centralManagerDidUpdateState(_ central: CBCentralManager) { if central.state == .poweredOn { //can start scanning peripherals centralManager.scanForPeripherals(withServices: [ArduinoPeripheral.ArduinoServiceUUID], options: nil) StateLabel.text = "Scanning for devices..." } } //result of scan - call to this method reflects a detected advertisement packet of a BLE peripheral in range func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) { //found peripheral so stop scanning self.centralManager.stopScan() //copy the peripheral instance self.peripheral = peripheral self.peripheral.delegate = self //connect to peripheral self.centralManager.connect(self.peripheral, options: nil) } //if successfully connected func centralManager(_ central: CBCentralManager, didConnect peripheral: CBPeripheral) { //check if this is the desired peripheral if peripheral == self.peripheral { //start service discovery for desired service peripheral.discoverServices([ArduinoPeripheral.ArduinoServiceUUID]) StateLabel.text = "Connected!" } } //handle service discovery event func peripheral(_ peripheral: CBPeripheral, didDiscoverServices error: Error?) { //cycle through available services if let services = peripheral.services { for service in services { //find the service from arduino if service.uuid == ArduinoPeripheral.ArduinoServiceUUID { //start discovery of the service's characteristics peripheral.discoverCharacteristics([ArduinoPeripheral.ArduinoCharacteristicUUID], for: service) StateLabel.text = "Service found" return } } } } //handle discovery of characteristics func peripheral(_ peripheral: CBPeripheral, didDiscoverCharacteristicsFor service: CBService, error: Error?) { if let characteristics = service.characteristics { for characteristic in characteristics { if characteristic.uuid == ArduinoPeripheral.ArduinoCharacteristicUUID { StateVar = characteristic StateLabel.text = "Characteristic found" } } } } //subscribe to characteristic for value change / notification func subscribeToNotifications(peripheral: CBPeripheral, characteristic: CBCharacteristic) { peripheral.setNotifyValue(true, for: characteristic) StateLabel.text = "Subscribed" } //notification update func peripheral(_ peripheral: CBPeripheral, didUpdateNotificationStateFor characteristic: CBCharacteristic, error: Error?) { if let error = error { // Handle error print(error) return } // Successfully subscribed to or unsubscribed from notifications/indications on a characteristic } //read value func readValue(characteristic: CBCharacteristic) { self.peripheral.readValue(for: characteristic) } //value returned from readValue func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) { if let error = error { // Handle error print(error) return } StateLabel.text = "Value updated" } } Where the Arduino characteristic UUUID and service UUID are defined in another swift file. I know it is connecting to the Arduino because the label says "Connected" when debugging, but it seems to get stuck on the line: "for service in services" and I am not sure why. Thank you for the help!

Hello, I am reading the value of a characteristic sent from an Arduino (peripheral) via Bluetooth. However, when attempting to print the value, it only prints an empty string. I cannot even compare the value to another variable (integer or string) because it cannot be converted from type Data. I have tried turning it into a UTF8 (string), ascii string, etc. but nothing seems to be working. Here is my code and some things I've tried: import UIKit import CoreBluetooth //local central device object class BluetoothViewController: UIViewController, CBPeripheralDelegate, CBCentralManagerDelegate { //properties private var centralManager: CBCentralManager! private var peripheral: CBPeripheral! //label to display stage of gait cycle @IBOutlet weak var StateLabel: UILabel! //characteristics private var StateVar: CBCharacteristic? override func viewDidLoad() { super.viewDidLoad() centralManager = CBCentralManager(delegate: self, queue: nil) } //a bunch of core bluetooth functions connecting to peripheral and finding the Arduino's serivce... //handle discovery of characteristics... subscribe to notifications... //notification update func peripheral(_ peripheral: CBPeripheral, didUpdateNotificationStateFor characteristic: CBCharacteristic, error: Error?) { if let error = error { // Handle error print(error) return } // Successfully subscribed to or unsubscribed from notifications/indications on a characteristic } //read value func readValue(characteristic: CBCharacteristic) { self.peripheral.readValue(for: characteristic) } //value returned from readValue func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) { if let error = error { // Handle error print(error) return } //var charASCIIval = NSString() //guard let StateVar = characteristic.value else { return } guard let StateVar = characteristic.value, let stringFromData = String(data: StateVar, encoding: .utf8) else { return } //let stringVal = String(decoding: StateVar, as: UTF8.self) //let stringVal = "\u{StateVar}" //let stringVal = String(UnicodeScalar(StateVar)) //let StateVar = string.StateVar(using: .utf8) print(stringFromData) StateLabel.text = stringFromData //if([readCBUUIDs containsObject: [ArduinoPeripheral.ArduinoCharacteristicUUID]]) //let ASCIIstring = NSString(data: StateVar, encoding: String.Encoding.utf8.rawValue) //else { return } //charASCIIval = ASCIIstring //guard let StateVarInt = StateVar as? UInt8 else { return } //StateLabel.text = String(data: StateVar, encoding: String.Encoding.ascii)! //StateLabel.text = "Value updated" //let StateVar = StateVar as! UInt8 //State machine if StateVar == 0 { StateLabel.text = "Leg Hold" } else if StateVar == 1 { StateLabel.text = "Swing" } else if StateVar == 2 { StateLabel.text = "Heel Step" } else if StateVar == 3 { StateLabel.text = "Drag Heel" } else if StateVar == 4 { StateLabel.text = "Toe Off" } else if StateVar == 5 { StateLabel.text = "Drag Toe" } else if StateVar == 6 { StateLabel.text = "Stance" } else if StateVar == 7 { StateLabel.text = "Drag All" } else if StateVar == 8 { StateLabel.text = "Leg Moving Backwards" } } // initT (_ source T) where T: BinaryInteger // init init(clamping:) } I would like to compare the value of the characteristic to a number (0-8) so I can output the correct stage of the gait cycle but I get the error: Referencing operator function '==' on 'BinaryInteger' requires that 'Data' conform to 'BinaryInteger' Please help!! Thank you!

Hello, My app has a settings page where the user can toggle buttons etc and I would like those values to carry over to the next screen / view controller file so that I can display different things depending on what the user inputted. I have tried everything from state and binding variables to cocoa touch class with a segue that can modify the variables of the destination view controller, but I always get errors. I'm not sure if it's because I'm using a more recent version of swift? But here is my code and some of the things I've tried: Settings page: import UIKit class SessionSetupViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate { //@State var visualBool = true //var feedbackAmt: String = "String" //var feedbackAmt = String() @IBAction func VisualToggle(_ sender: Any) { } @IBAction func AuditoryToggle(_ sender: Any) { } @IBOutlet weak var PickerLabel: UILabel! @IBOutlet weak var FeedbkAmtPicker: UIPickerView! let amounts = ["Low", "Medium", "High"] func numberOfComponents(in pickerView: UIPickerView) - Int { return 1 } func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) - String? { return amounts[row] } func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) - Int { return amounts.count } func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) { PickerLabel.text = amounts[row] //feedbackAmt = amounts[row] //let feedbackAmt = amounts[row] } @IBAction func BeginButtonPressed(_ sender: Any) { self.performSegue(withIdentifier: "BeginSegue", sender: self) } override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view. } // override func prepare(for segue: UIStoryboardSegue, sender: Any?) { // if segue.identifier == "BeginSegue" { // let destinationController = segue.destination as! BluetoothViewController // destinationController.feedbackAmt = PickerLabel.text! // } // } } And then the destination view controller: import UIKit import CoreBluetooth //local central device object class BluetoothViewController: UIViewController, CBPeripheralDelegate, CBCentralManagerDelegate { //properties private var centralManager: CBCentralManager! private var peripheral: CBPeripheral! var feedbackAmt = String() // from session setup view controller //var sessionSetupViewController: SessionSetupViewController? //let bluetoothViewController = BluetoothViewController() //let sessionSetupViewController = SessionSetupViewController() //bluetoothViewController.sessionSetupViewController = sessionSetupViewController //sessionSetupViewControler?.feedbackAmt //label to display stage of gait cycle @IBOutlet weak var StateLabel: UILabel! //characteristics private var StateVar: CBCharacteristic? override func viewDidLoad() { super.viewDidLoad() centralManager = CBCentralManager(delegate: self, queue: nil) //StateLabel.text = "\(ArduinoPeripheral.ArduinoCharacteristicUUID)" //StateLabel.text = "\(SessionSetupViewController.feedbackAmt)" //StateLabel.text = feedbackAmt } // core bluetooth functions... Please let me know if there is another way I can pass those values/settings to the next view controller. Thanks!

Hello, I am trying to play sound in my app but I'm having trouble adding the AVFoundation framework to my app by going to the general tab in xcode project properties... but I don't have "project properties" anywhere in my xcode (it should be the newest version). How do I add this framework? Is there any way to bypass this? Can I import AVFoundation without the framework? Thanks!