问题描述
我正在为 iOS 的 BLE 连接创建一个应用程序。 我可以从中央（iPhone6：iOS12.9）连接到外围设备并发送命令 我可以使用 writevalue 发送命令。
https://developer.apple.com/documentation/corebluetooth/cbperipheral/1518949-setnotifyvalue
在上面的setNotifyValue中，有一个描述，似乎被indicate接受了。 didUpdateValueFor 的以下方法不返回。
/// When changing the characteristic
func peripheral(_ peripheral: CBPeripheral,didUpdateValueFor characteristic: CBCharacteristic,error: Error?) {
https://developer.apple.com/documentation/corebluetooth/cbperipheraldelegate/1518708-peripheral
如果你知道如何在instruct中实现接收数据，请告诉我。
示例代码如下所示。 我还在努力，所以可能会有一些垃圾代码，抱歉。
// ViewController.swift
import UIKit
import CoreBluetooth
import os
class ViewController: UIViewController {
/// https://qiita.com/eKushida/items/def628e0eff6c106d467
var serviceUUID : CBUUID!
var characteristicUUID : CBUUID!
var responseCharacteristicUUID : CBUUID!
var centralManager: CBCentralManager!
var peripheral: CBPeripheral!
var writeCharacteristic: CBCharacteristic!
var responsCharacteristic: CBCharacteristic!
var data = Data()
@IBOutlet weak var dispLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
setup()
dispLabel.text = "Startup"
}
/// Initialize the central manager and UUID
private func setup() {
// Create an object representing the UUID.
self.serviceUUID = CBUUID(string: "XXXXX0000-XXXX-XXXX-XXXX-XXXXXXXXXX")
self.characteristicUUID = CBUUID(string: "XXXX2001-XXXX-XXXX-XXXX-XXXXXXXXXXXX")
self.responseCharacteristicUUID = CBUUID(string: "XXXX2000-XXXX-XXXX-XXXX-XXXXXXXXXXXX")
}
/// Pairing process
@IBAction func scan(_ sender: UIButton) {
print("Pairing process")
dispLabel.text = "Pairing process pressed"
self.centralManager = CBCentralManager(delegate: self,queue: nil)
}
/// Communication connection
@IBAction func connect(_ sender: UIButton) {
print("Communication connection")
/// https://qiita.com/MashMorgan/items/32500f158cb08d565786
/// https://knkomko.hatenablog.com/entry/2019/07/16/013443
let message = "**COMMAND**"
let command = message + "\r"
let writeData = Data(command.utf8)
print("writeData:" + String(data: writeData,encoding: .utf8)!)
peripheral.writeValue(writeData,for: writeCharacteristic,type: CBCharacteristicWriteType.withResponse)
}
}
//MARK : - CBCentralManagerDelegate
extension ViewController: CBCentralManagerDelegate {
func centralManagerDidUpdateState(_ central: CBCentralManager) {
switch central.state {
//wait for power on and scan
case CBManagerState.poweredOn:
let services: [CBUUID] = [serviceUUID] ///serviceUUID
centralManager.scanForperipherals(withServices: nil,options: nil)
// centralManager.scanForperipherals(withServices: services,options: nil)
print("isScanning:" + String(centralManager.isScanning))
default:
break
}
}
/// Called when a peripheral is discovered
func centralManager(_ central: CBCentralManager,diddiscover peripheral: CBPeripheral,advertisementData: [String : Any],RSSi RSSI: NSNumber) {
self.peripheral = peripheral
print("peripheral.name:" + String(peripheral.name ? "") + " peripheral.id:" + peripheral.identifier.uuidString)
if "XXXXXXX" == peripheral.name {
//start connection
self.centralManager.connect(self.peripheral,options: nil)
//peripheral is found,stop scanning
centralManager.stopScan()
}
}
/// called when connected
func centralManager(_ central: CBCentralManager,didConnect peripheral: CBPeripheral) {
print("Connection successful serviceUUID:" + serviceUUID.uuidString)
peripheral.delegate = self
peripheral.discoverServices([serviceUUID])
dispLabel.text = "Peripheral connection successful"
}
/// Called when the connection fails
func centralManager(_ central: CBCentralManager,didFailToConnect peripheral: CBPeripheral,error: Error?) {
print("Connection Failed")
}
/// When disconnected
func centralManager(_ central: CBCentralManager,diddisconnectPeripheral peripheral: CBPeripheral,error: Error?) {
print("disconnection: \(String(describing: error))")
}
}
//MARK : - CBPeripheralDelegate
extension ViewController: CBPeripheralDelegate {
/// Called when the characteristic is found
func peripheral(_ peripheral: CBPeripheral,DiddiscovercharacteristicsFor service: CBService,error: Error?) {
if error ! = nil {
print(error.debugDescription)
return
}
guard let servicecharacteristics = service.characteristics else {
// error handling
return
}
// Processing by characteristic
for characreristic in servicecharacteristics {
if characreristic.uuid == characteristicUUID
{
// keep the characteristic for writing data
self.writeCharacteristic = characreristic
print("Write characreristic / UUID:" + characreristic.uuid.uuidString)
print("Write characreristic / properties: \(self.writeCharacteristic.properties)")
continue
}
if characreristic.uuid == responseCharacteristicUUID {
peripheral.setNotifyValue(true,for: characreristic)
self.responsesCharacteristic = characreristic
print("Responses characreristic / UUID:" + characreristic.uuid.uuidString)
print("Responses characreristic / properties: \(self.responsesCharacteristic.properties)")
continue
}
print("Other characreristic / UUID:" + characreristic.uuid.uuidString)
}
}
func peripheral(_ peripheral: CBPeripheral,diddiscoverIncludedServicesFor: CBService,error: Error?){
print("peripheral diddiscoverIncludedServicesFor")
}
/// When writing data to the characteristic (called when sending a command)
func peripheral(_ peripheral: CBPeripheral,didWriteValueFor characteristic: CBCharacteristic,error: Error?) {
print("peripheral didWriteValueFor")
guard error == nil else {
print("Error when writing characteristic data: \(String(describing: error))")
// failure handling
return
}
print(characteristic.value)
}
func peripheral(peripheral: CBPeripheral,didUpdateNotificationStateForCharacteristic characteristic: CBCharacteristic,error: NSError?)
{
print("peripheral didUpdateNotificationStateForCharacteristic")
if let error = error {
print("Notify state update Failed.... .error: \(error)")
} else {
print("Notify state update succeeded! isnotifying: \(characteristic.isnotifying)")
}
}
func peripheral(peripheral: CBPeripheral,didUpdateValueForCharacteristic characteristic: CBCharacteristic,error: NSError?)
{
print("peripheral didUpdateValueForCharacteristic")
if let error = error {
print("Data update notification error: \(error)")
return
}
print("Data update! value: \(characteristic.value)")
}
/// When changing the characteristic
func peripheral(_ peripheral: CBPeripheral,error: Error?) {
print("peripheral didUpdateValueFor")
guard error == nil else {
print("Error getting/changing characteristic value: \(String(describing: error))")
// failure handling
return
}
guard let data = characteristic.value else {
print("characteristic.value")
// failure process
return
}
// data will be passed to us
print(data)
}
}
解决方法
我有示例 iOS 项目（中央和外设）发送/接收指示：https://github.com/alexanderlavrushko/BLEProof-collection
setNotifyValue here 的调用方式与您类似，应该没问题。
我建议检查外设端如何创建和更新特征的方式，iOS example link。
还有一个很棒的 iOS 应用程序 LightBlue，它可以模拟 BLE 设备，请参阅this guide：
- 中心 - 主题“订阅特征”可能有用
- 外设 - “添加新的虚拟外设”，但使用空白设备并配置您需要的服务/特性