Android 12设备BLE连接无法彻底断开问题求助

我遇到了一个BLE连接相关的问题：

• 首次可正常连接BLE设备，但断开后扫描无法再找到该设备
• 完全关闭应用后设备仍处于不可发现状态，仅重启手机后设备才恢复可被扫描状态
• 该问题仅出现在Android 12的Pixel、华为、小米设备上，运行Android 12的三星设备无此异常

目前我使用以下代码断开连接：

gatt.close()

我推测Android 12存在某种独立于应用的连接维持机制，想请教是否有其他方法能确保设备被彻底断开？

编辑1 #

调用close()断开后，执行以下代码仍返回已连接的设备：

bluetoothManager.getConnectedDevices(BluetoothProfile.GATT)

编辑2 #

我可以通过以下代码复现问题：

private var gatt: BluetoothGatt? = null
@SuppressLint("MissingPermission")
fun onDeviceClick(macAddress: String) {
    logger.i(TAG, "onDeviceClick(macAddress=$macAddress)")
    val bluetoothManager: BluetoothManager =
        context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
    if (gatt != null) {
        logger.i(TAG, "Disconnecting")
        gatt?.close()
        gatt = null
        printConnectedDevices(bluetoothManager)
        return
    }
    printConnectedDevices(bluetoothManager)
    val btDevice = bluetoothManager.adapter.getRemoteDevice(macAddress)
    logger.d(TAG, "Device to connect: $btDevice")
    gatt = btDevice.connectGatt(context, false, object : BluetoothGattCallback() {
        override fun onConnectionStateChange(gatt: BluetoothGatt?, status: Int, newState: Int) {
            super.onConnectionStateChange(gatt, status, newState)
            logger.d(TAG, "Connection state changed to status: $status, sate: $newState")
            when (newState) {
                BluetoothProfile.STATE_CONNECTED -> {
                    logger.d(TAG, "Connected")
                    printConnectedDevices(bluetoothManager)
                }
                BluetoothProfile.STATE_DISCONNECTED -> {
                    logger.d(TAG, "Disconnected")
                    printConnectedDevices(bluetoothManager)
                }
            }
        }
    })
}

@SuppressLint("MissingPermission")
private fun printConnectedDevices(bluetoothManager: BluetoothManager) {
    val btDevices = bluetoothManager.getConnectedDevices(BluetoothProfile.GATT)
    logger.d(TAG, "Currently connected devices: $btDevices")
}

操作步骤：调用一次onDeviceClick连接设备，再次调用断开。断开后Pixel设备的日志显示蓝牙适配器仍标记该设备为已连接：

I/SelectDeviceViewModel: onDeviceClick(macAddress=00:1E:42:35:F0:4D)
D/SelectDeviceViewModel: Currently connected devices: []
D/SelectDeviceViewModel: Device to connect: 00:1E:42:35:F0:4D
D/BluetoothGatt: connect() - device: 00:1E:42:35:F0:4D, auto: false
D/BluetoothGatt: registerApp()
D/BluetoothGatt: registerApp() - UUID=ae98a387-cfca-43db-82f0-45fd141979ee
D/BluetoothGatt: onClientRegistered() - status=0 clientIf=12
D/BluetoothGatt: onClientConnectionState() - status=0 clientIf=12 device=00:1E:42:35:F0:4D
D/SelectDeviceViewModel: Connection state changed to status: 0, sate: 2
D/SelectDeviceViewModel: Connected
D/SelectDeviceViewModel: Currently connected devices: [00:1E:42:35:F0:4D]
D/BluetoothGatt: onConnectionUpdated() - Device=00:1E:42:35:F0:4D interval=6 latency=0 timeout=500 status=0
D/BluetoothGatt: onConnectionUpdated() - Device=00:1E:42:35:F0:4D interval=36 latency=0 timeout=500 status=0
D/BluetoothGatt: onConnectionUpdated() - Device=00:1E:42:35:F0:4D interval=9 latency=0 timeout=600 status=0
I/SelectDeviceViewModel: onDeviceClick(macAddress=00:1E:42:35:F0:4D)
I/SelectDeviceViewModel: Disconnecting
D/BluetoothGatt: close()
D/BluetoothGatt: unregisterApp() - mClientIf=12
D/SelectDeviceViewModel: Currently connected devices: [00:1E:42:35:F0:4D]

编辑3 #

正常工作的三星Android 12设备日志：

I/SelectDeviceViewModel: onDeviceClick(macAddress=00:1E:42:35:F0:4D)
D/SelectDeviceViewModel: Currently connected devices: []
D/SelectDeviceViewModel: Device to connect: 00:1E:42:35:F0:4D
I/BluetoothAdapter: STATE_ON
D/BluetoothGatt: connect() - device: 00:1E:42:35:F0:4D, auto: false
I/BluetoothAdapter: isSecureModeEnabled
D/BluetoothGatt: registerApp()
D/BluetoothGatt: registerApp() - UUID=931b9526-ffae-402a-a4b4-3f01edc76e46
D/BluetoothGatt: onClientRegistered() - status=0 clientIf=17
D/BluetoothGatt: onTimeSync() - eventCount=0 offset=346
D/BluetoothGatt: onClientConnectionState() - status=0 clientIf=17 device=00:1E:42:35:F0:4D
D/SelectDeviceViewModel: Connection state changed to status: 0, sate: 2
D/SelectDeviceViewModel: Connected
D/SelectDeviceViewModel: Currently connected devices: [00:1E:42:35:F0:4D]
D/BluetoothGatt: onConnectionUpdated() - Device=00:1E:42:35:F0:4D interval=6 latency=0 timeout=500 status=0
D/BluetoothGatt: onConnectionUpdated() - Device=00:1E:42:35:F0:4D interval=38 latency=0 timeout=500 status=0
D/BluetoothGatt: onConnectionUpdated() - Device=00:1E:42:35:F0:4D interval=9 latency=0 timeout=600 status=0
I/SelectDeviceViewModel: onDeviceClick(macAddress=00:1E:42:35:F0:4D)
I/SelectDeviceViewModel: Disconnecting
D/BluetoothGatt: close()
D/BluetoothGatt: unregisterApp() - mClientIf=17
D/SelectDeviceViewModel: Currently connected devices: []

编辑4 #

我尝试修改断开逻辑，先调用disconnect()，等待连接状态变为断开后再调用close()，但问题仍然存在。

内容的提问来源于stack exchange，提问作者SMGhost