Here's how I start scanning BLE devices
if(bluetoothLeScanner!=null) {
bluetoothLeScanner.startScan(scanCallback);
isScanning = true;
}
How and when do I set isScanning to false?
Is there a way to find it inside of scanCallback?
private ScanCallback scanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, final ScanResult result) {
super.onScanResult(callbackType, result);
if(result==null) return;
runOnUiThread(new Runnable() {
#Override
public void run() {
bluetoothDeviceAdapter.update(result.getDevice());
bluetoothDeviceAdapter.notifyDataSetChanged();
}
});
// This doesn't mean end of scan does it?
// isScanning = false;
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
super.onBatchScanResults(results);
final List<BluetoothDevice> deviceList = new ArrayList<>();
for(ScanResult result: results)
deviceList.add(result.getDevice());
runOnUiThread(new Runnable() {
#Override
public void run() {
bluetoothDeviceAdapter.updateBatch(deviceList);
bluetoothDeviceAdapter.notifyDataSetChanged();
}
});
// This doesn't mean end of scan does it?
// isScanning = false;
}
};
The scan runs until
You explicitly stop it.
The onScanFailed callback is called.
Bluetooth is turned off.
Related
I am trying to scan for BLE devices around me. All i am getting is error code 2 and in some other occasions 'onBatchScanResults' returns empty list indefinitely. I am using redmi note 4 device. Thanks in advance.
My code :
BluetoothAdapter adapter = BluetoothAdapter.getDefaultAdapter();
final BluetoothLeScanner scanner = adapter.getBluetoothLeScanner();
final ScanSettings scanSettings = new ScanSettings.Builder()
.setScanMode(ScanSettings.SCAN_MODE_LOW_POWER)
.setCallbackType(ScanSettings.CALLBACK_TYPE_ALL_MATCHES)
.setMatchMode(ScanSettings.MATCH_MODE_STICKY)
.setNumOfMatches(ScanSettings.MATCH_NUM_MAX_ADVERTISEMENT)
.setReportDelay(1000L)
//.setLegacy(true)
.build();
btn_Scan.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Log.e(TAG, "onClick: ");
Thread thread = new Thread(new Runnable() {
#Override
public void run() {
if (scanner != null) {
Log.e(TAG, "scanner: ");
scanner.startScan(null, scanSettings, new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
super.onScanResult(callbackType, result);
Log.e(TAG, "onScanResult: " + result);
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
super.onBatchScanResults(results);
Log.e(TAG, "onBatchScanResults: " + results);
}
#Override
public void onScanFailed(int errorCode) {
super.onScanFailed(errorCode);
Log.e(TAG, "onScanFailed: ### " + errorCode);
}
});
} else {
Log.e(TAG, "could not get scanner object");
}
}
});
thread.start();
}
});
I am trying to develop an Android app capable to connect to a BLE device. But i have a problem to find ble devices. The scanLeDevice methods run but I have no callback. You can find my code below: I use Log.i() to display ble devices.
With another app (downloaded from the store) I can find my ble device and others bluetooth around. So It's not my phone's problem.
Thanks for help!
public class MainActivity extends AppCompatActivity {
private BluetoothAdapter bluetoothAdapter;
private final int REQUEST_ENABLE_BT = 1;
private boolean mScanning;
// Stops scanning after 10 seconds.
private static final long SCAN_PERIOD = 10000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.i("MainActivity", "Begin");
// Initializes Bluetooth adapter.
final BluetoothManager bluetoothManager =
(BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
bluetoothAdapter = bluetoothManager.getAdapter();
// Ensures Bluetooth is available on the device and it is enabled. If not,
// displays a dialog requesting user permission to enable Bluetooth.
if (bluetoothAdapter == null || !bluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
Log.i("MainActivity", "End for permissions");
if(Build.VERSION.SDK_INT < 21){
scanLeDevice(true);
}else{
scanDevice(true);
}
}
private Handler handler = new Handler();
private void scanLeDevice(final boolean enable) {
if (enable) {
// Stops scanning after a pre-defined scan period.
handler.postDelayed(new Runnable() {
#Override
public void run() {
mScanning = false;
bluetoothAdapter.stopLeScan(leScanCallback);
}
}, SCAN_PERIOD);
mScanning = true;
bluetoothAdapter.startLeScan(leScanCallback);
Log.i("MainActivity", "scanning");
} else {
mScanning = false;
bluetoothAdapter.stopLeScan(leScanCallback);
}
}
// Device scan callback.
private BluetoothAdapter.LeScanCallback leScanCallback =
new BluetoothAdapter.LeScanCallback() {
#Override
public void onLeScan(final BluetoothDevice device, int rssi,
byte[] scanRecord) {
runOnUiThread(new Runnable() {
#Override
public void run() {
//Ici///////////////////////////////////////
Log.i("MainActivity", "Nam: "+device.getName()+" Adresse: "+device.getAddress());
if(device.getName() != null && device.getName().equals("RN4871-85D7"))
scanLeDevice(false);
}
});
}
};
///////////////////Scan for API 21
private ScanSettings settings;
private List<ScanFilter> filters;
private BluetoothLeScanner mLEScanner;
private void scanDevice(final boolean enable){
if (mLEScanner==null){
mLEScanner = bluetoothAdapter.getBluetoothLeScanner();
settings = new ScanSettings.Builder()
.setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
.build();
filters = new ArrayList<ScanFilter>();
}
if (enable) {
if (mScanning) return;
// Stops scanning after a pre-defined scan period.
handler.postDelayed(new Runnable() {
#Override
public void run() {
if (!mScanning) return;
try {
mScanning = false;
//Log.d("MainActivity","STOP SCAN AFTER DELAY");
mLEScanner.stopScan(mScanCallback);
Log.i("MainActivity", "stop scanning API 21");
} catch (Exception e){Log.e("MainActivity",e.getMessage());}
}
}, SCAN_PERIOD);
mScanning = true;
//Log.d("MainActivity","START SCAN FROM EXPLICIT CALL");
mLEScanner.startScan(filters, settings, mScanCallback);
Log.i("MainActivity", "scanning API 21");
} else if (mLEScanner!=null){
if (!mScanning) return;
mScanning = false;
try {
//Log.d("MainActivity","STOP SCAN FROM EXPLICIT CALL");
mLEScanner.stopScan(mScanCallback);
Log.i("MainActivity", "stop scanning API 21");
} catch (Exception e){Log.i("MainActivity",e.getMessage());}
}
}
//call back for API 21
//#TargetApi(21)
private ScanCallback mScanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
super.onScanResult(callbackType, result);
Log.i("MainActivity", "onScanResult API 21");
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
super.onBatchScanResults(results);
Log.i("MainActivity", "onBatchScanResults API 21");
}
#Override
public void onScanFailed(int errorCode) {
super.onScanFailed(errorCode);
Log.i("MainActivity", "onScanFailed API 21");
}
};
}
Thanks for your help``
I found what was the problem about the location.
In fact, if you work with a API >= 23, you have to authorize you app to access to the location (not only in the Manifest file, but in you code it self).
So if you have the same problem:
First, manualy, go to your phon's setting and autorize your app to access to location: to be sure that was the problem.
Then add the code below so that, The application ask the user to authorize the application to access the location
/////////////////////////Location/////
#TargetApi(Build.VERSION_CODES.M)
private void loadPermissions(String perm,int requestCode) {
if (ContextCompat.checkSelfPermission(this, perm) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this, perm)) {
ActivityCompat.requestPermissions(this, new String[]{perm},requestCode);
}
} else if (checkLocationEnabled())
initScanner();
}
private boolean checkLocationEnabled(){
LocationManager lm = (LocationManager)this.getSystemService(Context.LOCATION_SERVICE);
boolean gps_enabled = false;
boolean network_enabled = false;
try {
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
} catch(Exception ex) {}
try {
network_enabled = lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
} catch(Exception ex) {}
if(!gps_enabled && !network_enabled) {
// notify user
AlertDialog.Builder dialog = new AlertDialog.Builder(this);
dialog.setMessage("GPS desabled");
dialog.setPositiveButton("Open GPS settings", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
// TODO Auto-generated method stub
Intent myIntent = new Intent( Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(myIntent);
//get gps
}
});
dialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
// TODO Auto-generated method stub
}
});
dialog.show();
return false;
} else return true;
}
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
switch (requestCode) {
case REQUEST_FINE_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// granted
if (checkLocationEnabled())
initScanner();
}
else{
// no granted
}
return;
}
}
}
I had this problem too because I was using ACCESS_COARSE_LOCATION on the permission.
When I changed to ACCESS_FINE_LOCATION, it finally works for me!
Basically, I am an iOS developer. I have a requirement to scan, connect & disconnect BLE devices. Everything works fine in iOS. Then I tried the following code to scan in Android. None of the devices re scanned at anytime. Could anyone help me, if I am doing something wrong.
public class MainActivity extends AppCompatActivity {
BluetoothAdapter bluetoothAdapter;
TextView statusTextView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
statusTextView = (TextView)findViewById(R.id.statusTxtView);
}
#Override
protected void onStart() {
super.onStart();
enableBluetooth();
}
private void enableBluetooth() {
final BluetoothManager bluetoothManager =
(BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
bluetoothAdapter = bluetoothManager.getAdapter();
if (bluetoothAdapter == null || !bluetoothAdapter.isEnabled()) {
statusTextView.setText("BT disabled");
Intent enableBtIntent =
new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, 1);
} else {
statusTextView.setText("BT enabled");
}
boolean status = bluetoothAdapter.startDiscovery();
if (status == true) {
statusTextView.setText("Start scanning");
} else {
statusTextView.setText("Failed scanning");
}
}
BluetoothAdapter.LeScanCallback scanCallback = new BluetoothAdapter.LeScanCallback() {
#Override
public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {
statusTextView.setText(device.getName());
}
};
}
You've not started scanning. After starting bluetooth discovery using bluetoothAdapter.startDiscovery(), you have to start scanning in order to get scan results. Use the following code to start scan.
I've not tested it but it should work as follows:
BluetoothLeScanner scanner = bluetoothAdapter.getBluetoothLeScanner();
scanner.startScan(scanCallback);
where scanCallback is the above callback you have created but unused.
Make sure that you have BLUETOOTH_ADMIN permission.
First you have to scan device
#SuppressLint("NewApi")
private void turnonBLE() {
// TODO Auto-generated method stub
manager = (BluetoothManager) getSystemService(BLUETOOTH_SERVICE);
mBLEAdapter = manager.getAdapter();
mLeScanner = mBLEAdapter.getBluetoothLeScanner();
mBLEAdapter.enable();
scanLeDevice(true);
Toast.makeText(getApplicationContext(), "BTLE ON Service",
Toast.LENGTH_LONG).show();
Log.e("BLE_Scanner", "TurnOnBLE");
}
If you are not using any uuid then scan without uuid
public void scanLeDevice(final boolean enable) {
if (enable) {
if (Build.VERSION.SDK_INT < 21) {
mBLEAdapter.startLeScan(mLeScanCallback);
} else {
ParcelUuid uuid = ParcelUuid.fromString(UUIDList.SENSOR_MAIN_SERVICE_UUID_STRING.toString());
ScanFilter scanFilter = new ScanFilter.Builder().setServiceUuid(uuid).build();
ScanSettings settings = new ScanSettings.Builder()
.setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
.setReportDelay(0)
.build();
if (mLeScanner != null)
mLeScanner.startScan(Collections.singletonList(scanFilter), settings, mScanCallback);
}
} else {
if (Build.VERSION.SDK_INT < 21) {
mBLEAdapter.stopLeScan(mLeScanCallback);
} else {
mLeScanner.stopScan(mScanCallback);
}
}
}
From that call scanCallback
private ScanCallback mScanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
BluetoothDevice btDevice = result.getDevice();
connectToDevice(btDevice, result.getScanRecord().getBytes());
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
for (ScanResult sr : results) {
Log.e("ScanResult - Results", sr.toString());
}
}
#Override
public void onScanFailed(int errorCode) {
Log.e("Scan Failed", "Error Code: " + errorCode);
}
};
for connect device call gattCallback
private synchronized void connectToDevice(BluetoothDevice device, byte[] scanRecord) {
mGatt = device.connectGatt(getApplicationContext(), false, mBtGattCallback);
}
private BluetoothGattCallback mBtGattCallback = new BluetoothGattCallback() {
// override all methods
}
I have all the permissions granted.
I use the beaconManager. which I create like this:
beaconManager = BeaconManager.getInstanceForApplication(this);
beaconManager.getBeaconParsers().add(new BeaconParser().
setBeaconLayout(BeaconParser.EDDYSTONE_UID_LAYOUT));
beaconManager.getBeaconParsers().add(new BeaconParser().
setBeaconLayout(BeaconParser.EDDYSTONE_TLM_LAYOUT));
beaconManager.getBeaconParsers().add(new BeaconParser().
setBeaconLayout(BeaconParser.EDDYSTONE_URL_LAYOUT));
beaconManager.bind(this);
OnBeaconConnect I do this:
#Override
public void onBeaconServiceConnect() {
ArrayList<Identifier> identifiers = new ArrayList<>();
// Set null to indicate that we want to match beacons with any value
identifiers.add(null);
// Represents a criteria of fields used to match beacon
try {
Region region = new Region("all-beacons-region", null, null, null);
Region region2 = new Region("de3be3ce-4770-477b-8893-0f0e5aeb9b98", null, null, null);
// Tells the BeaconService to start looking for beacons that match the passed Region object
beaconManager.startRangingBeaconsInRegion(region);
beaconManager.startRangingBeaconsInRegion(region2);
beaconManager.startMonitoringBeaconsInRegion(region);
beaconManager.startMonitoringBeaconsInRegion(region2);
} catch (RemoteException e) {
e.printStackTrace();
}
// Specifies a class that should be called each time the BeaconService gets ranging data, once per second by default
beaconManager.addRangeNotifier(this);
beaconManager.addMonitorNotifier(new MonitorNotifier() {
#Override
public void didEnterRegion(Region region) {
Log.i(TAG, "I just saw an beacon for the first time!");
}
#Override
public void didExitRegion(Region region) {
Log.i(TAG, "I no longer see an beacon");
}
#Override
public void didDetermineStateForRegion(int state, Region region) {
Log.i(TAG, "I have just switched from seeing/not seeing beacons: " + state);
}
});
}
And didRangeBeaconsInRegion has this:
#Override
public void didRangeBeaconsInRegion(Collection<Beacon> beacons, Region region) {
if (beacons.size() > 0) {
Log.i(TAG, "The first beacon I see is about " + beacons.iterator().next().getDistance() + " meters away.");
}
}
But the monitorNotifier never gets called, and the rangeNotifier gets called, but beacons size is always 0.
Why don't I get the beacons here?
PS: I even tried hardcoding a beacon, using the UUID, but still I get nothing in monitorNotifier, and still size 0 in the range notifier
It looks to me like you set up three beacon parsers for the Eddystone formats, but you are trying to detect a beacon sending out the iBeacon format. (I say this based on the first identifier in the second region definition being a 16 byte UUID.) If this is indeed what you are trying to do, please add a beacon parser for the iBeacon format. You can find that here:
https://beaconlayout.wordpress.com/
Also, if you are trying to detect on Android 6+ make sure you have obtained location permissions otherwise you won't detect anything. See here:
https://altbeacon.github.io/android-beacon-library/requesting_permission.html
you can try this
public class BLEActivity extends ActionBarActivity {
private BluetoothAdapter mBluetoothAdapter;
private int REQUEST_ENABLE_BT = 1;
private Handler mHandler;
private static final long SCAN_PERIOD = 10000;
private BluetoothLeScanner mLEScanner;
private ScanSettings settings;
private List<ScanFilter> filters;
private BluetoothGatt mGatt;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mHandler = new Handler();
if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
Toast.makeText(this, "BLE Not Supported",
Toast.LENGTH_SHORT).show();
finish();
}
final BluetoothManager bluetoothManager =
(BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = bluetoothManager.getAdapter();
}
#Override
protected void onResume() {
super.onResume();
if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
} else {
if (Build.VERSION.SDK_INT >= 21) {
mLEScanner = mBluetoothAdapter.getBluetoothLeScanner();
settings = new ScanSettings.Builder()
.setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
.build();
filters = new ArrayList<ScanFilter>();
}
scanLeDevice(true);
}
}
#Override
protected void onPause() {
super.onPause();
if (mBluetoothAdapter != null && mBluetoothAdapter.isEnabled()) {
scanLeDevice(false);
}
}
#Override
protected void onDestroy() {
if (mGatt == null) {
return;
}
mGatt.close();
mGatt = null;
super.onDestroy();
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_ENABLE_BT) {
if (resultCode == Activity.RESULT_CANCELED) {
//Bluetooth not enabled.
finish();
return;
}
}
super.onActivityResult(requestCode, resultCode, data);
}
private void scanLeDevice(final boolean enable) {
if (enable) {
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
if (Build.VERSION.SDK_INT < 21) {
mBluetoothAdapter.stopLeScan(mLeScanCallback);
} else {
mLEScanner.stopScan(mScanCallback);
}
}
}, SCAN_PERIOD);
if (Build.VERSION.SDK_INT < 21) {
mBluetoothAdapter.startLeScan(mLeScanCallback);
} else {
mLEScanner.startScan(filters, settings, mScanCallback);
}
} else {
if (Build.VERSION.SDK_INT < 21) {
mBluetoothAdapter.stopLeScan(mLeScanCallback);
} else {
mLEScanner.stopScan(mScanCallback);
}
}
}
private ScanCallback mScanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
Log.i("callbackType", String.valueOf(callbackType));
Log.i("result", result.toString());
BluetoothDevice btDevice = result.getDevice();
connectToDevice(btDevice);
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
for (ScanResult sr : results) {
Log.i("ScanResult - Results", sr.toString());
}
}
#Override
public void onScanFailed(int errorCode) {
Log.e("Scan Failed", "Error Code: " + errorCode);
}
};
private BluetoothAdapter.LeScanCallback mLeScanCallback =
new BluetoothAdapter.LeScanCallback() {
#Override
public void onLeScan(final BluetoothDevice device, int rssi,
byte[] scanRecord) {
runOnUiThread(new Runnable() {
#Override
public void run() {
Log.i("onLeScan", device.toString());
connectToDevice(device);
}
});
}
};
public void connectToDevice(BluetoothDevice device) {
if (mGatt == null) {
mGatt = device.connectGatt(this, false, gattCallback);
scanLeDevice(false);// will stop after first device detection
}
}
private final BluetoothGattCallback gattCallback = new BluetoothGattCallback() {
#Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
Log.i("onConnectionStateChange", "Status: " + status);
switch (newState) {
case BluetoothProfile.STATE_CONNECTED:
Log.i("gattCallback", "STATE_CONNECTED");
gatt.discoverServices();
break;
case BluetoothProfile.STATE_DISCONNECTED:
Log.e("gattCallback", "STATE_DISCONNECTED");
break;
default:
Log.e("gattCallback", "STATE_OTHER");
}
}
#Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
List<BluetoothGattService> services = gatt.getServices();
Log.i("onServicesDiscovered", services.toString());
gatt.readCharacteristic(services.get(1).getCharacteristics().get
(0));
}
#Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic
characteristic, int status) {
Log.i("onCharacteristicRead", characteristic.toString());
gatt.disconnect();
}
};
}
I have issues with android and BLE, any time i make a scan my app crash and i don't know the reason. I use startLeScan() can this be the reason?
Here is a sample of my code.
here is the place where I initialize for api 18
//API 18
private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() {
#Override
public void onLeScan(final BluetoothDevice device, int rssi,
byte[] scanRecord) {
Sensortag sensortag = new Sensortag(device, SensortagScanner.this,
mSensortagScannerCallback);
synchronized (this) {
for (Sensortag other : mDiscoveredDevices) {
if (sensortag.getName().equals(other.getName())) {
Log.i("SensortagScanner",
"Discovered duplicate device: "
+ other.getName());
return;
}
}
}
mDiscoveredDevices.add(sensortag);
Log.i("SensortagScanner",
"Discovered a device named " + device.getName() + ".");
mCallback.onSensorDiscovered(sensortag);
}
};
here is where i initialize ScanCall and what seems to be wrong looking the error java nulle exception
//API 21
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
private void initScanCallback() {
if (scanCallback != null)
return;
this.scanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
super.onScanResult(callbackType, result);
// Do whatever you want
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
super.onBatchScanResults(results);
Log.d(TAG, "Batch scan results: ");
for (ScanResult result : results) {
Log.d(TAG, "Batch scan result: " + result.toString());
// Do whatever you want
}
}
#Override
public void onScanFailed(int errorCode) {
super.onScanFailed(errorCode);
// scanListener.onScanFinished();
Log.d(TAG, "Scan failed");
}
};
}
here is where i start the scan
#Override
public void startScan(SensorScannerCallback callback) {
mCallback = callback;
if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) {
callback.onScannerUnavailable(this);
return;
}
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
stopScan();
}
}, SCAN_PERIOD);
Log.i("SensortagScanner", "Starting scan...");
mScanning = true;
// ////////////POUR API 21//////////////
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
mBluetoothAdapter.getBluetoothLeScanner().startScan(scanCallback);
}
// /////////POUR API <18////////////////
else {
mBluetoothAdapter.startLeScan(mLeScanCallback);
}
}
try using the method for Android 5 like in the snippet below. It might help.
If it does not, please show more of your code and the error you have when the crash happens.
First, you need a callback, so initialize it correctly depending on the android version.
private void initScanCallback(){
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
initCallbackLollipop();
}else{
initScanCallbackSupport();
}
}
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
private void initCallbackLollipop(){
if(scanCallback != null) return;
this.scanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
super.onScanResult(callbackType, result);
//Do whatever you want
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
super.onBatchScanResults(results);
Log.d(TAG, "Batch scan results: ");
for (ScanResult result: results){
Log.d(TAG, "Batch scan result: " + result.toString());
//Do whatever you want
}
}
#Override
public void onScanFailed(int errorCode) {
super.onScanFailed(errorCode);
Log.d(TAG, "Scan failed");
}
};
}
private void initScanCallbackSupport(){
if(callback != null) return;
this.callback = new BluetoothAdapter.LeScanCallback() {
#Override
public void onLeScan(final BluetoothDevice device, int rssi, final byte[] scanRecord) {
String address = device.toString();
String name = device.getName();
// parse uuids according to another stackoverflow post
//List<UUID> uuids = parseUuids(scanRecord);
// TODO Compare detected UUIDs with the uuidFilter
//for(UUID discUUID : uuids)
// for(UUID uuid : BLEScanService.this.uuidFilter)
// if(discUUID.equals(uuid))
BLEScanService.this.scanListener.onDeviceScanned(address, name, uuids, rssi);
}
};
}
Then you can start the scan according to the android version:
public void startScanWithServices(List<String> uuidFilters){
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
scanLollipop(uuidFilters);
}else{
scanSupport(uuidFilters);
}
// Store filters for later filtering
int size = uuidFilters.size();
this.uuidFilter = new ArrayList<UUID>();
for(int i = 0; i<size; i++){
this.uuidFilter.add(UUID.fromString(uuidFilters.get(i)));
}
if(BuildConfig.DEBUG) Log.d(TAG, "BLE Scan started");
}
#TargetApi(Build.VERSION_CODES.LOLLIPOP)
private void scanLollipop(List<String> uuidFilters){
if(scanCallback == null)
initCallbackLollipop();
List<ScanFilter> filters = new ArrayList<ScanFilter>();
ScanSettings settings = new ScanSettings.Builder()
.setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY) // or BALANCED previously
.setReportDelay(0)
.build();
bluetoothAdapter.getBluetoothLeScanner().startScan(filters, settings, scanCallback);
//bluetoothAdapter.getBluetoothLeScanner().startScan(scanCallback);
}
private void scanSupport(List<String> uuidFilters){
if(callback == null)
initScanCallbackSupport();
//start scan
//boolean success = bluetoothAdapter.startLeScan(uuids, callback);
boolean success = bluetoothAdapter.startLeScan(callback);
//check scan success
if(!success) {
if(BuildConfig.DEBUG) Log.d(TAG, "BLE Scan failed");
scanListener.onScanFinished();
}
}
And then you can stop the scan like this:
public void stopScan(){
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
// Stop scan and flush pending scan
bluetoothAdapter.getBluetoothLeScanner().flushPendingScanResults(scanCallback);
bluetoothAdapter.getBluetoothLeScanner().stopScan(scanCallback);
}else{
bluetoothAdapter.stopLeScan(callback);
}
if(BuildConfig.DEBUG) Log.d(TAG, "BLE Scan stopted");
}
Check your manifest file. You should have these permissions
<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>