title: BluetoothLeScanner could not find callback wrapper
body: <p>Because of I had problems with Bluetooth on Android Lollipop, I have tried to change the scanner method. <br>
  So I have tried to use the new package.
  In the previous version, I called startScan(mLeScanCallback) and everything works but now, when I call startScan(mScanCallback) I have the error: "D/BluetoothLeScanner: could not find callback wrapper".<br>
  No devices are found and the ListAdapter, I use to show the devices, is empty.</p>
  
  <p>The comment lines are the previous code (and it worked!).
  This my code:</p>
  
  <pre><code>public class Selection extends ListActivity implements ServiceConnection {
  
  public void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
  
          mHandler = new Handler();
  
          // Initializes a Bluetooth adapter through BluetoothManager.
          final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
          mBluetoothAdapter = bluetoothManager.getAdapter();
  
  
  
          getApplicationContext().bindService(new Intent(this, MetaWearBleService.class), this, Context.BIND_AUTO_CREATE);
  
  }
  
  private void scanLeDevice(final boolean enable) {
      final BluetoothLeScanner bluetoothLeScanner = mBluetoothAdapter.getBluetoothLeScanner();
  
      if (enable) {
  
          mHandler.postDelayed(new Runnable() {
              @Override
              public void run() {
  
                  //mBluetoothAdapter.stopLeScan(mLeScanCallback);
                  bluetoothLeScanner.stopScan(mScanCallback);
                  setListAdapter(listAdapter);
  
              }
          }, SCAN_PERIOD);
  
  
          //mBluetoothAdapter.startLeScan(mLeScanCallback);
          bluetoothLeScanner.startScan(mScanCallback);
  
     } else {
  
          //mBluetoothAdapter.stopLeScan(mLeScanCallback);
          bluetoothLeScanner.stopScan(mScanCallback);
          setListAdapter(listAdapter);
  
      }
  
  
  }
  
  private ScanCallback mScanCallback =
          new ScanCallback() {
  
              public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
                  runOnUiThread(new Runnable() {
                      @Override
                      public void run() {
  
                          listAdapter.addDevice(device);
  
                      }
                  });
              }
          };
  </code></pre>
  
  <p>Instead  the ListAdapter extends BaseAdapter and use a ViewHolder. If it necessary, I post it.</p>
  
  <p>So what does it mean "D/BluetoothLeScanner: could not find callback wrapper"? What is it wrong?</p>
  
  <p>Otherwise how I can't resolve the problem of scanning with the Android Lollipop?
  In Lollipop I have often errors about BluetoothGatt. I don't know to minized it (or solve it).</p>
  
  <p>Thanks</p>