justtwago

class Adapter : ListAdapter<Item, ItemViewHolder>(DiffUtilCallback) {
 
    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): SpotViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item, parent, false)
        return ItemViewHolder(view)
    }
 
    override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
        holder.bind(currentList[position])
    }

justtwago

fun renderItems(newItems: List){
    val diffResult: DiffUtil.DiffResult = DiffUtil.calculateDiff(DiffUtilCallback(oldItems, newItems))
    diffResult.dispatchUpdatesTo(this) // this : RecyclerView.Adapter
}

justtwago

class DiffUtilCallback(
    private val oldItems: List,
    private val newItems: List
) : DiffUtil.Callback() {
    override fun areItemsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
    return oldItems[oldItemPosition].id == newItems[newItemPosition].id
}
 
override fun areContentsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
    // It works properly if Item is a data class

justtwago

dependencies {
  implementation 'com.google.android.gms:play-services-location:17.0.0'
}

justtwago

val deviceNameUUID = UUID.fromString("00002a00-0000-1000-8000-00805f9b34fb")
val appearanceUUID = UUID.fromString("00002a01-0000-1000-8000-00805f9b34fb")
val batteryLevelUUID = UUID.fromString("00002a19-0000-1000-8000-00805f9b34fb")
val modelNumberUUID = UUID.fromString("00002A24-0000-1000-8000-00805f9b34fb")
val serialNumberUUID = UUID.fromString("00002A25-0000-1000-8000-00805f9b34fb")
val firmwareRevisionUUID = UUID.fromString("00002A26-0000-1000-8000-00805f9b34fb")
val hardwareRevisionUUID = UUID.fromString("00002A27-0000-1000-8000-00805f9b34fb")
val softwareRevisionUUID = UUID.fromString("00002A28-0000-1000-8000-00805f9b34fb")
val manufacturerNameUUID = UUID.fromString("00002A29-0000-1000-8000-00805f9b34fb")

justtwago

fun BluetoothSocket.setSocketAndStartConnector() {
    val socketThread: Thread = object : Thread() {
        override fun run() {
            try {
                BluetoothAdapter.getDefaultAdapter().cancelDiscovery()
                if (!isConnected) connect()

                inputStream
                // read the stream here

justtwago

private fun BluetoothDevice.createSocket(uuid: UUID): BluetoothSocket {
    return createInsecureRfcommSocketToServiceRecord(uuid)
}

justtwago

private val BluetoothDevice.isDeviceBonded get() = bondState == BluetoothDevice.BOND_BONDED

justtwago

private var leScanCallback: ScanCallback? = null

private fun startLEScan(doOnDeviceFound: (BluetoothDevice?) -> Unit) {
    leScanCallback = object : ScanCallback() {
        override fun onScanResult(callbackType: Int, result: ScanResult) {
            doOnDeviceFound(result.device)
        }
    }
    BluetoothAdapter.getDefaultAdapter().bluetoothLeScanner.startScan(leScanCallback)
}

justtwago

private fun scanDevices(
    context: Context,
    doOnDeviceFound: (BluetoothDevice?) -> Unit,
    doOnDiscoveryFinished: () -> Unit
) {
    val scanningBroadcastReceiver = object : BroadcastReceiver() {
        override fun onReceive(context: Context, intent: Intent) {
            when (intent.action) {
                BluetoothDevice.ACTION_FOUND -> {
                    val device = intent.getParcelableExtra<BluetoothDevice>(BluetoothDevice.EXTRA_DEVICE)