蓝牙低功耗代码不是扫描设备

Question

我在蓝牙LE场景中扫描设备的代码无效。它运行正常，没有任何异常或错误。但onLeScan（）函数（在leScanCallback中）根本没有调用，而其他蓝牙低功耗设备就在附近......

public class ScanBle extends Activity {

    private BluetoothAdapter myAdapter;
    private Handler bleHandler;
    private long SCAN_PERIOD = 10000;
    ArrayList<BluetoothDevice> allBleDevice;
    ArrayAdapter<String> listAdaptor;
    private String TagBle = "ScanBle";


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        BluetoothManager bm = (BluetoothManager) getSystemService(BLUETOOTH_SERVICE);
        myAdapter = bm.getAdapter();
        listAdaptor = new ArrayAdapter<>(this, R.layout.activity_scan_ble);
        allBleDevice = new ArrayList<BluetoothDevice>();
        bleHandler = new Handler();
    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        if(myAdapter == null || !myAdapter.isEnabled())
        {
            Intent enableBt = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivity(enableBt);
            finish();
            return;
        }
        if(!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE))
        {
            Toast.makeText(getApplicationContext(), "No Le Feature", Toast.LENGTH_SHORT).show();
            finish();
            return;
        }
        startScan(true);

        if(listAdaptor.getCount()>0)
        {
            ListView lv = new ListView(this);
            lv.setAdapter(listAdaptor);
            setContentView(lv);
        }
        else
        {
            Toast.makeText(this, "No Ble devices Found Bazingaaa", Toast.LENGTH_SHORT).show();
        }
    }   

    public void startScan(final boolean enable) {

        Log.d(TagBle , "startScan() started");
        // TODO Auto-generated method stub
        if(enable)
        {
            Toast.makeText(getApplicationContext(), "Scan is running...", Toast.LENGTH_SHORT).show();

            bleHandler.postDelayed(new Runnable() {

                @Override
                public void run() {
                    // TODO Auto-generated method stub
                    myAdapter.stopLeScan(callbackBle);
                }

            }, SCAN_PERIOD );
            myAdapter.startLeScan(callbackBle);

        }
        else
        {
            myAdapter.stopLeScan(callbackBle);
        }
    }


    public BluetoothAdapter.LeScanCallback callbackBle = new BluetoothAdapter.LeScanCallback() {

        @Override
        public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
            // TODO Auto-generated method stub
            Log.d(TagBle , "callBackBle() Running");
            runOnUiThread(new Runnable() {

                @Override
                public void run() {
                    // TODO Auto-generated method stub
                    BluetoothDevice tempDevice = device;
                    allBleDevice.add(tempDevice);
                    listAdaptor.add(tempDevice.getName()+"\n"+tempDevice.getAddress());
                }
            });
        }
    };
}