How to search paried devices Kotlin Android App-CodePudding

I am attempting to create an Android app to connect to a HC-05 Bluetooth module. I am going through the Android documentation, however, following the documentation I am receiving an error that I can not work around. I do not understand how to the list of bonded devices.

fun Bluetooth() {
    val pairedDevices: Set<BluetoothDevice>? = BluetoothAdapter.bondedDevices
    pairedDevices?.forEach { device ->
        val deviceName = device.name
        val deviceHardwareAddress = device.address // MAC address
    }

I am getting an error at the "= BluetoothAdapter.bondedDevices". I am trying to get the list of devices bonded to the Android phone and pick the HC-05 Bluetooth module to connect to.

I have tried reading through the documentation of the BluetoothAdapter and cannot figure out how to use the getBondedDevices() function. Any help would be appreciated greatly!

CodePudding user response：

getBondedDevices() is not a static function. You need to use the following way to get the BluetoothAdapter first:

val bluetoothManager = getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
val bluetoothAdapter = bluetoothManager.adapter

Deprecated way:

val bluetoothAdapter = BluetoothAdapter.getDefaultAdapter()

And then using bluetoothAdapter.bondedDevices should work.

But note that you have to also add the following permission in AndroidManifest.xml:

<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

CodePudding user response：

This procedure has to be done on a phone with developer options enabled connected to the laptop.

I put a break point on the line if (address==myaddress) and I stepped through the list examining devices with the debugger I used evaluate expression .and once I saw mydevice I copied its address out and I also copied the UUID out and made it hard coded in app just to get it working. Full code Android project is here and a You tube of project coming later tonight or tomorrow just got it working a few days ago. Like and subscribe if you like model trains some arduino mostly old model trains with a touch of underground modern electronics.

private fun getMySocket(): BluetoothSocket? {
    val bluetoothManager: BluetoothManager =
        context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
    if (danny117BTSocket == null) {
        if (checkSelfPermission(
                appC, android.Manifest.permission.BLUETOOTH_CONNECT
            ) == PackageManager.PERMISSION_GRANTED
        ) {
            val ada = bluetoothManager.adapter
            ada.bondedDevices.forEach {
                if (it.address == myAddress) {
                    danny117BTSocket = it.createRfcommSocketToServiceRecord(MY_UUID)
                }
            }
        }
    }