Ble:从Android发送广告数据到iOS

时间:2019-09-05 12:13:01

标签: android ios kotlin bluetooth-lowenergy

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)

,但似乎iOS无法读取自定义服务数据。

那么,有一种方法可以通过BLE向iOS发送一些小数据(少量字节)(并在Android为中心而iOS为外围设备时也接收数据)?

如果可能的话,我会避免在中央外围设备之间打开连接。

1 个答案:

答案 0 :(得分:1)

iOS对广告数据有严格的限制。无论是发送还是接收它,您都只能控制它的一小部分。它的大部分由iOS本身控制,并且在中央管理者的情况下甚至没有转发给应用程序。

Advertisement Data Retrieval Keys例外,适用于centralManager(_:didDiscover:advertisementData:rssi:) advertisementData 参数。

answer中提到了一个更具体的示例。

更新

即使其中一个键用于服务数据,我也不认为数据会转发到应用程序。但是我可能是错的。我想您是在问这个问题,因为未设置密钥CBAdvertisementDataServiceDataKey

更新2

我创建了一个最小的Android和iOS示例,并使它可以正常工作。我认为您的Android代码中没有明显的问题。因此,您需要与您的iOS同事交谈...

服务数据为“ ABC”(或十六进制的61 62 63),而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)
                }
            }
        }
    }
}