public AndroidBluetoothPacketProvider(Context context)
{
var manager = (BluetoothManager)context.GetSystemService("bluetooth");
_adapter = manager.Adapter;
_scanCallback = new BLEScanCallback();
}
public void Start()
{
SystemDebug.WriteLine($"{nameof(Start)}()", LogTag);
if (_adapter is null || _adapter.BluetoothLeScanner is null)
{
SystemDebug.WriteLine("adapter is null, please turn bluetooth on", LogTag);
return;
}
var scanSettings = new ScanSettings.Builder().SetScanMode(Android.Bluetooth.LE.ScanMode.LowPower).Build();
SystemDebug.WriteLine("starting scan", LogTag);
lock (_lock)
{
_cancellationTokenSource = new CancellationTokenSource();
_cancellationToken = _cancellationTokenSource.Token;
// if Start/Stop were called on different threads and start ran first the token
// will be canceled and this will cancel immediately anyways
_scanTask = Task.Run(async() =>
{
while (!_cancellationToken.IsCancellationRequested)
{
//SystemDebug.WriteLine("scanning for beacons...", LogTag);
var scanCallback = new BLEScanCallback();
scanCallback.OnAdvertisementPacketReceived += ScanCallback_OnAdvertisementPacketReceived;
_adapter.BluetoothLeScanner.StartScan(null, scanSettings, scanCallback);
try
{
await Task.Delay(ScanDurationMs, _cancellationToken);
}
catch (TaskCanceledException)
{
SystemDebug.WriteLine("Scan duration delay cancelled", LogTag);
}
//SystemDebug.WriteLine("scanning for beacons completed...", LogTag);
_adapter.BluetoothLeScanner.StopScan(scanCallback);
scanCallback.OnAdvertisementPacketReceived -= ScanCallback_OnAdvertisementPacketReceived;
//SystemDebug.WriteLine("scanning for beacons paused...", LogTag);
try
{
await Task.Delay(ScanDelayMs, _cancellationToken);
}
catch (TaskCanceledException)
{
SystemDebug.WriteLine("Scan delay cancelled", LogTag);
}
}
}, _cancellationToken);
}
}
