Finding BLE Devices

The following permissions are required to use the Bluetooth APIs:

android.permission.BLUETOOTH
android.permission.BLUETOOTH_ADMIN

If you’re targeting devices with Android 6.0 (API Level 23) or higher and want to perform scanning/advertising operations you will require a Location permission:

android.permission.ACCESS_FINE_LOCATION

or

android.permission.ACCESS_COARSE_LOCATION

Note.- Devices with Android 6.0 (API Level 23) or higher also need to have Location Services enabled.

A BluetoothAdapter object is required to start scanning/advertising operations:

BluetoothManager bluetoothManager = (BluetoothManager) context.getSystemService(Context.BLUETOOTH_SERVICE);
bluetoothAdapter = bluetoothManager.getAdapter();

The startScan (ScanCallback callback)method of the BluetoothLeScanner class is the most basic way to start a scanning operation. A ScanCallback object is required to receive results:

bluetoothAdapter.getBluetoothLeScanner().startScan(new ScanCallback() {
     @Override
     public void onScanResult(int callbackType, ScanResult result) {
     super.onScanResult(callbackType, result);
     Log.i(TAG, "Remote device name: " + result.getDevice().getName());
       }
    });