我必须通过 ble 将一些广告数据发送到 iOS 中央应用程序。在 Android 外围设备方面,当我创建广告时,我会这样做:
var byteArrayData = dataToSend.toByteArray(Charsets.UTF_8)
var data = AdvertiseData.Builder().apply {
addServiceData(
ParcelUuid(MY_SERVICE_UUID),
byteArrayData
)
}
bleAdvertiser.startAdvertising(mySettings.build(), data.build(), myAdvertiseCallback)
但iOS似乎无法读取自定义服务数据。
那么,有没有一种方法可以通过 BLE 将一些小数据(几个字节)发送到 iOS(并且当 Android 是中央设备而 iOS 是外围设备时也可以接收数据)?
如果可能的话,我会避免在中央设备和外围设备之间打开连接。
最佳答案
iOS 对广告数据的限制非常严格。在发送和接收时,您只能控制其中的一小部分。其中大部分由 iOS 本身控制,并且(如果是中央管理员角色)甚至不会转发到应用程序。
异常(exception)情况是 Advertisement Data Retrieval Keys ,适用于 centralManager(_:didDiscover:advertisementData:rssi:) 的 advertisementData 参数.
这个answer提到了一个更具体的例子.
更新
尽管其中一个键用于服务数据,但我认为数据不会转发到应用程序。但我可能错了。我猜您问这个问题是因为 key CBAdvertisementDataServiceDataKey
未设置。
更新 2
我创建了一个最小的 Android 和 iOS 示例,并且可以正常运行。我在你的 Android 代码中没有看到任何明显的问题。所以你需要和你的 iOS 同事谈谈......
服务数据为“ABC”(或十六进制的 61 62 63
),16 位 UUID 为 FF01
。 iOS 日志输出为:
2019-09-05 16:39:18.987142+0200 BleScanner[18568:3982403] [Scanner] Advertisement data: FF01: <616263>
Android - MainActivity.kt
package bleadvertiser
import android.bluetooth.BluetoothManager
import android.content.Context
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
class MainActivity : AppCompatActivity() {
private var peripheral: Peripheral? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
}
override fun onStart() {
super.onStart()
val bluetoothManager = getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
peripheral = Peripheral(bluetoothManager.adapter)
peripheral?.startAdvertising()
}
}
Android - Peripheral.kt
package bleadvertiser
import android.bluetooth.BluetoothAdapter
import android.bluetooth.le.AdvertiseCallback
import android.bluetooth.le.AdvertiseData
import android.bluetooth.le.AdvertiseSettings
import android.os.ParcelUuid
import android.util.Log
import java.util.*
private const val TAG = "Peripheral"
class Peripheral(private val bluetoothAdapter: BluetoothAdapter) {
fun startAdvertising() {
val advertiseSettings = AdvertiseSettings.Builder().build()
val serviceData = "abc".toByteArray(Charsets.UTF_8)
val advertiseData = AdvertiseData.Builder()
.addServiceData(ParcelUuid(SERVICE_UUID), serviceData)
.build()
val advertiser = bluetoothAdapter.bluetoothLeAdvertiser
advertiser.startAdvertising(advertiseSettings, advertiseData, advertiseCallback)
}
private val advertiseCallback = object: AdvertiseCallback() {
override fun onStartFailure(errorCode: Int) {
Log.w(TAG, String.format("Advertisement failure (code %d)", errorCode))
}
override fun onStartSuccess(settingsInEffect: AdvertiseSettings?) {
Log.i(TAG, "Advertisement started")
}
}
companion object {
val SERVICE_UUID: UUID = UUID.fromString("0000ff01-0000-1000-8000-00805F9B34FB")
}
}
iOS - ViewController.swift
import UIKit
class ViewController: UIViewController {
var bleScanner: BleScanner?
override func viewDidLoad() {
super.viewDidLoad()
bleScanner = BleScanner()
}
}
iOS - BleScanner.swift
import Foundation
import CoreBluetooth
import os.log
class BleScanner : NSObject {
static let serviceUUID = CBUUID(string: "FF01")
static let log = OSLog(subsystem: Bundle.main.bundleIdentifier!, category: "Scanner")
private var centralManager: CBCentralManager!
private var scanningTimer: Timer?
override init() {
super.init()
centralManager = CBCentralManager(delegate: self, queue: nil)
}
func startScanning() {
scanningTimer = Timer.scheduledTimer(withTimeInterval: TimeInterval(20), repeats: false, block: { (_) in
self.stopScanning()
})
centralManager.scanForPeripherals(withServices: [ BleScanner.serviceUUID ], options: nil)
}
func stopScanning() {
centralManager.stopScan()
}
}
extension BleScanner : CBCentralManagerDelegate {
func centralManagerDidUpdateState(_ central: CBCentralManager) {
if centralManager.state == .poweredOn {
startScanning()
}
}
func centralManager(_ central: CBCentralManager, didDiscover peripheral: CBPeripheral, advertisementData: [String : Any], rssi RSSI: NSNumber) {
for (key, value) in advertisementData {
if key == CBAdvertisementDataServiceDataKey {
let serviceData = value as! [CBUUID : NSData]
for (uuid, data) in serviceData {
os_log("Advertisement data: %{public}s: %{public}s", log: BleScanner.log, type: .info, uuid.uuidString, data.debugDescription)
}
}
}
}
}
关于android - 布莱 : Send advertise data to iOS from Android,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/57805222/