Develop Reference

Bluetooth BLE does not connect

I tried all ways but i can't connect to the other bluetooth device. I perform these steps:
scan devices
stop scan when I find the device with "A-"
connect to device
I can find all the devices but then I can't connect to the one I want. Unfortunately I can't find a complete example
This is the code I use:
import android.Manifest;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothManager;
import android.bluetooth.BluetoothProfile;
import android.bluetooth.le.BluetoothLeScanner;
import android.bluetooth.le.ScanCallback;
import android.bluetooth.le.ScanResult;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.text.method.ScrollingMovementMethod;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import java.util.List;
import java.util.Map;
import java.util.UUID;
public class MainActivity extends AppCompatActivity {
BluetoothManager btManager;
BluetoothAdapter btAdapter;
BluetoothLeScanner btScanner;
Button startScanningButton;
Button stopScanningButton;
TextView peripheralTextView;
BluetoothGatt bluetoothGatt;
BluetoothDevice device;
private final static int REQUEST_ENABLE_BT = 1;
private static final int PERMISSION_REQUEST_COARSE_LOCATION = 2;
private boolean mEchoInitialized;
private static final String TAG = "ClientActivity";
//
// private ActivityClientBinding mBinding;
private boolean mScanning;
private Handler mHandler;
private Handler mLogHandler;
private Map<String, BluetoothDevice> mScanResults;
private boolean mConnected;
private ScanCallback mScanCallback;
public static String SERVICE_STRING = "7D2EA28A-F7BD-485A-BD9D-92AD6ECFE93E";
public static UUID SERVICE_UUID = UUID.fromString(SERVICE_STRING);
public static String CHARACTERISTIC_ECHO_STRING = "7D2EBAAD-F7BD-485A-BD9D-92AD6ECFE93E";
public static UUID CHARACTERISTIC_ECHO_UUID = UUID.fromString(CHARACTERISTIC_ECHO_STRING);
public static final long SCAN_PERIOD = 5000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
peripheralTextView = (TextView) findViewById(R.id.PeripheralTextView);
peripheralTextView.setMovementMethod(new ScrollingMovementMethod());
startScanningButton = (Button) findViewById(R.id.StartScanButton);
startScanningButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
startScanning();
}
});
stopScanningButton = (Button) findViewById(R.id.StopScanButton);
stopScanningButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
stopScanning();
}
});
stopScanningButton.setVisibility(View.INVISIBLE);
btManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
btAdapter = btManager.getAdapter();
btScanner = btAdapter.getBluetoothLeScanner();
if (btAdapter != null && !btAdapter.isEnabled()) {
Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
}
// Make sure we have access coarse location enabled, if not, prompt the user to enable it
if (this.checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("This app needs location access");
builder.setMessage("Please grant location access so this app can detect peripherals.");
builder.setPositiveButton(android.R.string.ok, null);
builder.setOnDismissListener(new DialogInterface.OnDismissListener() {
#Override
public void onDismiss(DialogInterface dialog) {
requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION}, PERMISSION_REQUEST_COARSE_LOCATION);
}
});
builder.show();
}
}
#Override
protected void onResume() {
super.onResume();
// Check low energy support
if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
// Get a newer device
// logError("No LE Support.");
finish();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private ScanCallback leScanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
// Log.d("ci sono",result.getDevice().getName());
if (result.getDevice().getName() != null && result.getDevice().getName().contains("A-"))
stopScanning();
// peripheralTextView.append("Device Name: " + result.getDevice().getName() + " rssi: " + result.getRssi() + "\n");
// auto scroll for text view
// final int scrollAmount = peripheralTextView.getLayout().getLineTop(peripheralTextView.getLineCount()) - peripheralTextView.getHeight();
// if there is no need to scroll, scrollAmount will be <=0
// if (scrollAmount > 0)
// peripheralTextView.scrollTo(0, scrollAmount);
connectDevice(result.getDevice());
// bluetoothGatt = result.getDevice().connectGatt(MainActivity.this, false, gattClientCallback);
}
};
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case PERMISSION_REQUEST_COARSE_LOCATION: {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
System.out.println("coarse location permission granted");
} else {
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Functionality limited");
builder.setMessage("Since location access has not been granted, this app will not be able to discover beacons when in the background.");
builder.setPositiveButton(android.R.string.ok, null);
builder.setOnDismissListener(new DialogInterface.OnDismissListener() {
#Override
public void onDismiss(DialogInterface dialog) {
}
});
builder.show();
}
return;
}
}
}
public void startScanning() {
System.out.println("start scanning");
peripheralTextView.setText("");
startScanningButton.setVisibility(View.INVISIBLE);
stopScanningButton.setVisibility(View.VISIBLE);
AsyncTask.execute(new Runnable() {
#Override
public void run() {
btScanner.startScan(leScanCallback);
}
});
}
public void stopScanning() {
System.out.println("stopping scanning");
peripheralTextView.append("Stopped Scanning");
startScanningButton.setVisibility(View.VISIBLE);
stopScanningButton.setVisibility(View.INVISIBLE);
AsyncTask.execute(new Runnable() {
#Override
public void run() {
btScanner.stopScan(leScanCallback);
}
});
}
private void connectDevice(BluetoothDevice device) {
// log("Connecting to " + device.getAddress());
GattClientCallback gattClientCallback = new GattClientCallback();
bluetoothGatt = device.connectGatt(this, false, gattClientCallback);
}
protected void onStop() {
// call the superclass method first
super.onStop();
Log.d("spegni", "bluetooth");
btScanner.stopScan(leScanCallback);
}
private class GattClientCallback extends BluetoothGattCallback {
#Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
super.onConnectionStateChange(gatt, status, newState);
// log("onConnectionStateChange newState: " + newState);
if (status == BluetoothGatt.GATT_FAILURE) {
// logError("Connection Gatt failure status " + status);
disconnectGattServer();
return;
} else if (status != BluetoothGatt.GATT_SUCCESS) {
// handle anything not SUCCESS as failure
// logError("Connection not GATT sucess status " + status);
disconnectGattServer();
return;
}
if (newState == BluetoothProfile.STATE_CONNECTED) {
// log("Connected to device " + gatt.getDevice().getAddress());
setConnected(true);
gatt.discoverServices();
Log.d("discoverRiuscito", "onServicesDiscovered " + status + " " + gatt.discoverServices()
+ " " + gatt.getServices());
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
// log("Disconnected from device");
disconnectGattServer();
}
}
#Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
super.onServicesDiscovered(gatt, status);
if (status != BluetoothGatt.GATT_SUCCESS) {
// log("Device service discovery unsuccessful, status " + status);
return;
}
List<BluetoothGattCharacteristic> matchingCharacteristics = BluetoothUtils.findCharacteristics(gatt);
if (matchingCharacteristics.isEmpty()) {
// logError("Unable to find characteristics.");
return;
}
// log("Initializing: setting write type and enabling notification");
for (BluetoothGattCharacteristic characteristic : matchingCharacteristics) {
characteristic.setWriteType(BluetoothGattCharacteristic.WRITE_TYPE_DEFAULT);
enableCharacteristicNotification(gatt, characteristic);
}
}
#Override
public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
super.onCharacteristicWrite(gatt, characteristic, status);
if (status == BluetoothGatt.GATT_SUCCESS) {
// log("Characteristic written successfully");
} else {
// logError("Characteristic write unsuccessful, status: " + status);
disconnectGattServer();
}
}
#Override
public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
super.onCharacteristicRead(gatt, characteristic, status);
if (status == BluetoothGatt.GATT_SUCCESS) {
// log("Characteristic read successfully");
readCharacteristic(characteristic);
} else {
// logError("Characteristic read unsuccessful, status: " + status);
// Trying to read from the Time Characteristic? It doesnt have the property or permissions
// set to allow this. Normally this would be an error and you would want to:
// disconnectGattServer();
}
}
#Override
public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
super.onCharacteristicChanged(gatt, characteristic);
// log("Characteristic changed, " + characteristic.getUuid().toString());
readCharacteristic(characteristic);
}
private void enableCharacteristicNotification(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
boolean characteristicWriteSuccess = gatt.setCharacteristicNotification(characteristic, true);
if (characteristicWriteSuccess) {
// log("Characteristic notification set successfully for " + characteristic.getUuid().toString());
if (BluetoothUtils.isEchoCharacteristic(characteristic)) {
initializeEcho();
}
} else {
// logError("Characteristic notification set failure for " + characteristic.getUuid().toString());
}
}
private void readCharacteristic(BluetoothGattCharacteristic characteristic) {
byte[] messageBytes = characteristic.getValue();
// log("Read: " + StringUtils.byteArrayInHexFormat(messageBytes));
String message = StringUtils.stringFromBytes(messageBytes);
if (message == null) {
// logError("Unable to convert bytes to string");
return;
}
// log("Received message: " + message);
}
}
public void setConnected(boolean connected) {
mConnected = connected;
}
private void sendMessage() {
BluetoothGattCharacteristic characteristic = BluetoothUtils.findEchoCharacteristic(bluetoothGatt);
if (characteristic == null) {
return;
}
String message = "2";
byte[] messageBytes = StringUtils.bytesFromString(message);
if (messageBytes.length == 0) {
return;
}
characteristic.setValue(messageBytes);
boolean success = bluetoothGatt.writeCharacteristic(characteristic);
if (success) {
// log("Wrote: " + StringUtils.byteArrayInHexFormat(messageBytes));
} else {
// logError("Failed to write data");
}
}
public void initializeEcho() {
mEchoInitialized = true;
}
private class BtleScanCallback extends ScanCallback {
private Map<String, BluetoothDevice> mScanResults;
BtleScanCallback(Map<String, BluetoothDevice> scanResults) {
mScanResults = scanResults;
}
#Override
public void onScanResult(int callbackType, ScanResult result) {
addScanResult(result);
}
#Override
public void onBatchScanResults(List<ScanResult> results) {
for (ScanResult result : results) {
addScanResult(result);
}
}
#Override
public void onScanFailed(int errorCode) {
}
private void addScanResult(ScanResult result) {
BluetoothDevice device = result.getDevice();
String deviceAddress = device.getAddress();
mScanResults.put(deviceAddress, device);
}
}
public void disconnectGattServer() {
mConnected = false;
mEchoInitialized = false;
if (bluetoothGatt != null) {
bluetoothGatt.disconnect();
bluetoothGatt.close();
}
}
}```

BLE error : D/BluetoothLeScanner: Scan failed, reason: app registration failed

I am getting this error sometimes while trying to scan BLE in android studio, usually after a while of using my app but cerntainly not all the time.
I am using a class especially for BT connection, this is what's inside:
package com.omri.goniometer;
import android.app.Application;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.le.BluetoothLeScanner;
import android.bluetooth.BluetoothProfile;
import android.bluetooth.le.ScanCallback;
import android.bluetooth.le.ScanResult;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.HandlerThread;
import android.util.Log;
import android.widget.Toast;
import android.os.Handler;
import java.util.List;
import java.util.UUID;
public class Bluetooth {
private final Context mContext;
private final MainActivity mActivity;
final String devcAddress = "D8:A0:1D:47:49:82";
// private static final UUID ServiceUUID = UUID.fromString("0000183B-0000-1000-8000-00805F9B34FB");
// private static final UUID CharUUID = UUID.fromString("00002A08-0000-1000-8000-00805F9B34FB");
private static final UUID ServiceUUID = UUID.fromString("da3a95de-467b-11ea-b77f-2e728ce88125");
private static final UUID CharUUID = UUID.fromString("da3a9836-467b-11ea-b77f-2e728ce88125");
private String scanDevcAddress = null;
private BluetoothAdapter mBTAdapter;
private boolean mScanning;
private static final long SCAN_PERIOD = 5000;
private BluetoothLeScanner mBluetoothLeScanner;
private BluetoothDevice BTdevice;
private BluetoothGatt mBTGatt;
private BluetoothGattCharacteristic mGattChar;
private int mConnectionState = STATE_DISCONNECTED;
private Short rollInt = 0;
private Short pitchInt = 0;
String rollString = "0";
String pitchString = "0";
private static final int STATE_DISCONNECTED = 0;
private static final int STATE_CONNECTING = 1;
private static final int STATE_CONNECTED = 2;
private static final int WAVE = 3;
private static final int BATTERY_UPDATE = 4;
String[] stringArray;
Handler mHandler;
public final static String ACTION_GATT_CONNECTED =
"com.example.bluetooth.le.ACTION_GATT_CONNECTED";
public final static String ACTION_GATT_DISCONNECTED =
"com.example.bluetooth.le.ACTION_GATT_DISCONNECTED";
public final static String ACTION_GATT_SERVICES_DISCOVERED =
"com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED";
public final static String ACTION_DATA_AVAILABLE =
"com.example.bluetooth.le.ACTION_DATA_AVAILABLE";
public final static String EXTRA_DATA =
"com.example.bluetooth.le.EXTRA_DATA";
Bluetooth(Context context, MainActivity activity) {
this.mContext = context;
this.mActivity = activity;
mHandler = new Handler();
disconnect();
close();
// Initializes Bluetooth adapter.
final BluetoothManager bluetoothManager =
(BluetoothManager) mContext.getSystemService(Context.BLUETOOTH_SERVICE);
mBTAdapter = bluetoothManager.getAdapter();
mBluetoothLeScanner = mBTAdapter.getBluetoothLeScanner();
if (mBTAdapter == null) {
// Device does not support Bluetooth
Toast.makeText(mContext, "Bluetooth device not found!", Toast.LENGTH_SHORT).show();
} else {
if (!mContext.getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
Toast.makeText(mContext, "no BLE feature in phone", Toast.LENGTH_SHORT).show();
}
searchDevice();
//connect();
}
}
public void searchDevice() {
if (mBTAdapter.isEnabled()) {
Log.d("ADebugTag", "After check if BTAdapter is enabled");
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
scanLeDevice(true);
}
}, 5000);
} else {
Toast.makeText(mContext, "To begin please turn on bluetooth", Toast.LENGTH_SHORT).show();
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
mActivity.startActivityForResult(enableBtIntent, MainActivity.REQUEST_ENABLE_BT);
}
}
private void scanLeDevice(final boolean enable) {
if (enable) {
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
mScanning = false;
mBluetoothLeScanner.stopScan(leScanCallback);
}
}, SCAN_PERIOD);
mScanning = true;
Log.d("ADebugTag", "Just before scan");
mBluetoothLeScanner.startScan(leScanCallback);
} else {
mScanning = false;
mBluetoothLeScanner.stopScan(leScanCallback);
}
}
// Device scan callback.
private ScanCallback leScanCallback = new ScanCallback() {
#Override
public void onScanResult(int callbackType, ScanResult result) {
Log.d("ADebugTag", "Inside scan callback scan");
BTdevice = result.getDevice();
scanDevcAddress = result.getDevice().getAddress();
Log.d("ADebugTag", "scanned address: " + scanDevcAddress);
if (scanDevcAddress.equals(devcAddress)) {
mActivity.updatesStatus(MainActivity.DEVICE_FOUND,"","");
//Intent deviceFoundIntent = new Intent(mActivity,MainActivity.class);
scanLeDevice(false);
//Toast.makeText(mContext, "Scanning stopped", Toast.LENGTH_SHORT).show();
}
}
};
public boolean connect() {
mActivity.updatesStatus(MainActivity.STATE_CONNECTING,"","");
BTdevice = mBTAdapter.getRemoteDevice(devcAddress);
mBTGatt = BTdevice.connectGatt(mContext, false, mGattCallback);
if (mBTGatt == null){
Log.d("ADebugTag", "mBTGatt is null");
return false;
}
else {
try {
mGattChar = mBTGatt.getService(ServiceUUID).getCharacteristic(CharUUID);
}
catch (NullPointerException e){
Log.d("ADebugTag", "mGattChar is null\n" + e);
}
//setCharacteristicNotification(mGattChar, true);
return true;
}
}
private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
#Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
String intentAction;
if (newState == BluetoothProfile.STATE_CONNECTED) {
intentAction = ACTION_GATT_CONNECTED;
mConnectionState = STATE_CONNECTED;
broadcastUpdate(intentAction);
mActivity.updatesStatus(MainActivity.STATE_CONNECTED,"","");
Log.d("ADebugTag", "Connected to GATT server.");
// Attempts to discover services after successful connection.
Log.d("ADebugTag", "Attempting to start service discovery:" + mBTGatt.discoverServices());
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
intentAction = ACTION_GATT_DISCONNECTED;
mConnectionState = STATE_DISCONNECTED;
mActivity.updatesStatus(MainActivity.STATE_DISCONNECTED,"","");
Log.d("ADebugTag", "Disconnected from GATT server.");
broadcastUpdate(intentAction);
}
}
#Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
if (mBTGatt ==null){
return;
}
else {
List<BluetoothGattService> services = getSupportedGattServices();
for (BluetoothGattService service : services) {
if (!service.getUuid().equals(ServiceUUID))
continue;
List<BluetoothGattCharacteristic> gattCharacteristics =
service.getCharacteristics();
// Loops through available Characteristics.
for (BluetoothGattCharacteristic gattCharacteristic : gattCharacteristics) {
if (!gattCharacteristic.getUuid().equals(CharUUID))
continue;
final int charaProp = gattCharacteristic.getProperties();
if ((charaProp | BluetoothGattCharacteristic.PROPERTY_NOTIFY) > 0) {
setCharacteristicNotification(gattCharacteristic, true);
} else {
Log.d("ADebugTag", "Characteristic does not support notify");
}
}
}
}
} else {
Log.d("ADebugTag", "onServicesDiscovered received:" + status);
}
}
#Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic,
int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
final byte[] dataInput = characteristic.getValue();
}
}
#Override
public void onCharacteristicChanged(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic) {
final byte[] dataInput = characteristic.getValue();
//Log.d("ADebugTag", "Data on changed: " + dataInput);
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
};
private void broadcastUpdate(final String action) {
final Intent intent = new Intent(action);
mContext.sendBroadcast(intent);
}
private void broadcastUpdate(final String action,
final BluetoothGattCharacteristic characteristic) {
final Intent intent = new Intent(action);
// For all other profiles, writes the data formatted in HEX.
if (characteristic == null) {
Log.d("ADebugTag", "characteristic is null in broadcastUpdate");
}
else {
final byte[] data = characteristic.getValue();
//Log.d("ADebugTag", "Data broadcast update: " + data);
if (data != null && data.length > 0) {
final StringBuilder stringBuilder = new StringBuilder(data.length);
for (byte byteChar : data)
stringBuilder.append(String.format("%X ", byteChar));
//stringBuilder.append(String.format("%d ", byteChar));
String ds = stringBuilder.toString();
intent.putExtra(EXTRA_DATA, new String(data) + "\n" + ds);
Log.d("ADebugTag", "Data complete string: " + ds);
stringArray = ds.split(" ");
rollInt = (short) Integer.parseInt(stringArray[3]+stringArray[2],16);
pitchInt = (short) Integer.parseInt(stringArray[1]+stringArray[0],16);
Log.d("ADebugTag", "Roll received:" + rollInt);
Log.d("ADebugTag", "Pitch received:" + pitchInt);
rollString = rollInt.toString();
pitchString = pitchInt.toString();
mActivity.updatesStatus(MainActivity.DATA_RECEIVED,rollString,pitchString);
//deciBattery = Integer.parseInt(bateryStringArray[0],16);
//updatesStatus(BATTERY_UPDATE);
}
mContext.sendBroadcast(intent);
}
}
public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic,
boolean enabled) {
if (mBTAdapter == null || mBTGatt == null) {
Log.d("ADebugTag", "BluetoothAdapter not initialized in set char");
return;
}
else {
//mGattChar = mBTGatt.getService()
mBTGatt.setCharacteristicNotification(characteristic, enabled);
// BluetoothGattDescriptor descriptor = characteristic.getDescriptor(CharUUID);
// descriptor.setValue(descriptor.ENABLE_NOTIFICATION_VALUE);
// mBTGatt.writeDescriptor(descriptor);
}
}
/**
* Disconnects an existing connection or cancel a pending connection. The disconnection result
* is reported asynchronously through the
* {#code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
* callback.
*/
public void disconnect() {
if (mBTAdapter == null || mBTGatt == null) {
Log.d("ADebugTag", "BluetoothAdapter not initialized");
return;
}
mBTGatt.disconnect();
}
public List<BluetoothGattService> getSupportedGattServices() {
if (mBTGatt == null) return null;
return mBTGatt.getServices();
}
/**
* After using a given BLE device, the app must call this method to ensure resources are
* released properly.
*/
public void close() {
if (mBTGatt == null) {
return;
}
mBTGatt.close();
mBTGatt = null;
}
}
Why is it not scanning? found a place that says you have to wait 5 seconds between D/BluetoothAdapter: STATE_ON and start scan but couldn't catch it and don't know if it's the issue at all.
Thanks.

BLE WRITE and Read Issue?

Please anyone help me, I already tried many ways.
BluetoothGatt mBluetoothGatt
mBluetoothGatt.writeCharacteristic(mWriteCharacteristic)
return true
but readCharacteristic(BluetoothGattCharacteristic characteristic) return false.I could not find correct manuals for this,but tried many ways there was no clear sample for BEL android.`
package com.example.android.bluetoothlegatt;
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattDescriptor;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.BluetoothProfile;
import android.content.Context;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.List;
import java.util.UUID;
import static com.example.android.bluetoothlegatt.DeviceControlActivity.hexArray;
public class BluetoothLeService extends Service {
private final static String TAG = BluetoothLeService.class.getSimpleName();
private BluetoothManager mBluetoothManager;
private BluetoothAdapter mBluetoothAdapter;
private String mBluetoothDeviceAddress;
private BluetoothGatt mBluetoothGatt;
private int mConnectionState = STATE_DISCONNECTED;
private static final int STATE_DISCONNECTED = 0;
private static final int STATE_CONNECTING = 1;
private static final int STATE_CONNECTED = 2;
public final static String ACTION_GATT_CONNECTED =
"com.example.bluetooth.le.ACTION_GATT_CONNECTED";
public final static String ACTION_GATT_DISCONNECTED =
"com.example.bluetooth.le.ACTION_GATT_DISCONNECTED";
public final static String ACTION_GATT_SERVICES_DISCOVERED =
"com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED";
public final static String ACTION_DATA_AVAILABLE =
"com.example.bluetooth.le.ACTION_DATA_AVAILABLE";
public final static String EXTRA_DATA =
"com.example.bluetooth.le.EXTRA_DATA";
public final static UUID UUID_HEART_RATE_MEASUREMENT =
UUID.fromString(SampleGattAttributes.HEART_RATE_MEASUREMENT);
private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
#Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
String intentAction;
if (newState == BluetoothProfile.STATE_CONNECTED) {
intentAction = ACTION_GATT_CONNECTED;
mConnectionState = STATE_CONNECTED;
broadcastUpdate(intentAction);
Log.i(TAG, "Connected to GATT server.");
Log.i(TAG, "Attempting to start service discovery:" +
mBluetoothGatt.discoverServices());
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
intentAction = ACTION_GATT_DISCONNECTED;
mConnectionState = STATE_DISCONNECTED;
Log.i(TAG, "Disconnected from GATT server.");
broadcastUpdate(intentAction);
}
}
#Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
} else {
Log.w(TAG, "onServicesDiscovered received: " + status);
}
}
#Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic,
int status) {
Log.i(TAG,"onCharacteristicRead::"+status);
if (status == BluetoothGatt.GATT_SUCCESS) {
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
}
#Override
public void onCharacteristicChanged(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic) {
Log.i(TAG,"onCharacteristicChanged::"+characteristic);
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
#Override
public void onCharacteristicWrite(final BluetoothGatt gatt, final BluetoothGattCharacteristic characteristic, int status) {
super.onCharacteristicWrite(gatt, characteristic, status);
byte[] data = characteristic.getValue();
Log.i(TAG,"onCharacteristicWrite Response::"+bytesToHex(data));
}
};
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for ( int j = 0; j < bytes.length; j++ ) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
private void broadcastUpdate(final String action) {
final Intent intent = new Intent(action);
sendBroadcast(intent);
}
private void broadcastUpdate(final String action,
final BluetoothGattCharacteristic characteristic) {
final Intent intent = new Intent(action);
if (UUID_HEART_RATE_MEASUREMENT.equals(characteristic.getUuid())) {
int flag = characteristic.getProperties();
int format = -1;
if ((flag & 0x01) != 0) {
format = BluetoothGattCharacteristic.FORMAT_UINT16;
Log.d(TAG, "Heart rate format UINT16.");
} else {
format = BluetoothGattCharacteristic.FORMAT_UINT8;
Log.d(TAG, "Heart rate format UINT8.");
}
final int heartRate = characteristic.getIntValue(format, 1);
Log.d(TAG, String.format("Received heart rate: %d", heartRate));
intent.putExtra(EXTRA_DATA, String.valueOf(heartRate));
} else {
final byte[] data = characteristic.getValue();
if (data != null && data.length > 0) {
final StringBuilder stringBuilder = new StringBuilder(data.length);
for(byte byteChar : data)
stringBuilder.append(String.format("%02X ", byteChar));
intent.putExtra(EXTRA_DATA, new String(data) + "\n" + stringBuilder.toString());
}
}
sendBroadcast(intent);
}
public class LocalBinder extends Binder {
BluetoothLeService getService() {
return BluetoothLeService.this;
}
}
#Override
public IBinder onBind(Intent intent) {
return mBinder;
}
#Override
public boolean onUnbind(Intent intent) {
close();
return super.onUnbind(intent);
}
private final IBinder mBinder = new LocalBinder();
public boolean initialize() {
if (mBluetoothManager == null) {
mBluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
if (mBluetoothManager == null) {
Log.e(TAG, "Unable to initialize BluetoothManager.");
return false;
}
}
mBluetoothAdapter = mBluetoothManager.getAdapter();
if (mBluetoothAdapter == null) {
Log.e(TAG, "Unable to obtain a BluetoothAdapter.");
return false;
}
return true;
}
public boolean connect(final String address) {
if (mBluetoothAdapter == null || address == null) {
Log.w(TAG, "BluetoothAdapter not initialized or unspecified address.");
return false;
}
if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress)
&& mBluetoothGatt != null) {
Log.d(TAG, "Trying to use an existing mBluetoothGatt for connection.");
if (mBluetoothGatt.connect()) {
mConnectionState = STATE_CONNECTING;
return true;
} else {
return false;
}
}
final BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
if (device == null) {
Log.w(TAG, "Device not found. Unable to connect.");
return false;
}
mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
Log.d(TAG, "Trying to create a new connection.");
mBluetoothDeviceAddress = address;
mConnectionState = STATE_CONNECTING;
return true;
}
public void disconnect() {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
mBluetoothGatt.disconnect();
}
public void close() {
if (mBluetoothGatt == null) {
return;
}
mBluetoothGatt.close();
mBluetoothGatt = null;
}
public void readCharacteristic(BluetoothGattCharacteristic characteristic) {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
mBluetoothGatt.readCharacteristic(characteristic);
}
public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic,
boolean enabled) {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
mBluetoothGatt.setCharacteristicNotification(characteristic, enabled);
if (UUID_HEART_RATE_MEASUREMENT.equals(characteristic.getUuid())) {
BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
UUID.fromString(SampleGattAttributes.CLIENT_CHARACTERISTIC_CONFIG));
descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
mBluetoothGatt.writeDescriptor(descriptor);
}
}
public List<BluetoothGattService> getSupportedGattServices() {
if (mBluetoothGatt == null) return null;
return mBluetoothGatt.getServices();
}
public void readCustomCharacteristic() {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
BluetoothGattService mCustomService = mBluetoothGatt.getService(UUID.fromString("0000bc01-0000-1000-8000-00805f9b34fb"));
if(mCustomService == null){
Log.w(TAG, "Custom BLE Service not found");
return;
}
BluetoothGattCharacteristic mReadCharacteristic = mCustomService.getCharacteristic(UUID.fromString("0000bd01-0000-1000-8000-00805f9b34fb"));
UUID uuid = UUID.fromString("00002901-0000-1000-8000-00805f9b34fb");
Log.i(TAG,"BluetoothGattCharacteristic Des::"+mReadCharacteristic.getDescriptor(uuid));
BluetoothGattDescriptor descriptor = mReadCharacteristic.getDescriptor(uuid);
Log.i(TAG,"BluetoothGattDescriptor is::"+descriptor.getUuid());
descriptor.setValue(BluetoothGattDescriptor.ENABLE_INDICATION_VALUE);
mBluetoothGatt.writeDescriptor(descriptor);
mBluetoothGatt.setCharacteristicNotification(mReadCharacteristic, true);
mReadCharacteristic = mCustomService.getCharacteristic(UUID.fromString("0000bd01-0000-1000-8000-00805f9b34fb"));
byte[] data = mReadCharacteristic.getValue();
Log.i(TAG,"onCharacteristicWrite Response::"+bytesToHex(data));
if(mBluetoothGatt.readCharacteristic(mReadCharacteristic) == false) {
Log.w(TAG, "Failed to read characteristic");
}
else{
Log.w(TAG, "Suucess to read characteristic");
mBluetoothGatt.notify();
}
}
public void writeCustomCharacteristic(byte value[]) {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
BluetoothGattService mCustomService = mBluetoothGatt.getService(UUID.fromString("0000bc01-0000-1000-8000-00805f9b34fb"));
if(mCustomService == null){
Log.w(TAG, "Custom BLE Service not found");
return;
}
BluetoothGattCharacteristic mWriteCharacteristic = mCustomService.getCharacteristic(UUID.fromString("0000bd01-0000-1000-8000-00805f9b34fb"));
try {
byte [] message = new byte [6];
message[0] = (byte) 0x1B;
message[1] = (byte) 0x00;
message[2] = (byte) 0x02;
message[3] = (byte) 0x25;
message[4] = (byte) 0x27;
message[5] = (byte) 0x1b;
mWriteCharacteristic.setValue(message);
if(mBluetoothGatt.writeCharacteristic(mWriteCharacteristic)==true){
Log.w(TAG, "Write Char Success");
}
else{
Log.w(TAG, "Write Char Faile");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
`

After you call mBluetoothGatt.writeDescriptor(descriptor); you need to wait for the corresponding callback until you can execute the read command.

onCharacteristicChanged() never called

I'm attempting to receive data from my Texas sensor tag, but so far I just managed to connect and write characteristics to it.
this is my setCharacteristicNotification();
the part commented below does not work and I didn't managed to use it.
public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic,
boolean enabled) {
if(bluetoothAdapter == null || bluetoothGatt == null) return;
bluetoothGatt.setCharacteristicNotification(characteristic, enabled);
if(GattUUIDs.containsUuid(characteristic.getUuid())) {
// BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
// UUID.fromString(GattAttributes.CLIENT_CHARACTERISTIC_CONFIG));
BluetoothGattDescriptor descriptor = new BluetoothGattDescriptor(
GattUUIDs.UUID_CLIENT_CHAR_CONFIG, BluetoothGattDescriptor.PERMISSION_WRITE |
BluetoothGattDescriptor.PERMISSION_READ);
descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
bluetoothGatt.writeDescriptor(descriptor);
}
}
When I try to call the commented block, this is what I receive:
java.lang.NullPointerException: Attempt to invoke virtual method
'boolean android.bluetooth.BluetoothGattDescriptor.setValue(byte[])'
on a null object reference
This is my Client Characteristic Configuration UUID:
public static final UUID UUID_CLIENT_CHAR_CONFIG =
UUID.fromString(GattAttributes.CLIENT_CHARACTERISTIC_CONFIG);
public static String CLIENT_CHARACTERISTIC_CONFIG = "f0002902-0451-4000-b000-000000000000";
I think that it has some sort of problem in my descriptor because I can register it but I never got a callback from it.
If it helps, this is my Service:
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattDescriptor;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.BluetoothProfile;
import android.content.Context;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
import java.util.List;
import java.util.UUID;
/**
* Created by alan on 2/23/16.
*/
public class DeviceService extends Service {
private final static String TAG = DeviceService.class.getSimpleName();
private BluetoothGatt bluetoothGatt;
private String deviceAddress;
private BluetoothManager bluetoothManager;
private BluetoothAdapter bluetoothAdapter;
private int connectionState = STATE_DISCONNECTED;
public final IBinder binder = new LocalBinder();
public static final int STATE_DISCONNECTED = 0;
public static final int STATE_CONNECTING = 1;
public static final int STATE_CONNECTED = 2;
public static final String ACTION_GATT_SERVICES_DISCOVERED = "action_gatt_services_discovered";
public static final String ACTION_GATT_DISCONNECTED = "action_gatt_disconnected";
public static final String ACTION_GATT_CONNECTED = "action_gatt_connected";
public static final String ACTION_DATA_AVAILABLE = "action_data_available";
public static final String ACTION_DATA_NOTIFY = "action_data_notify";
public static final String ACTION_DATA_WRITE = "action_data_write";
public static final String ACTION_DATA_READ = "action_data_read";
public static final String EXTRA_DATA = "extra_data";
#Override
public IBinder onBind(Intent intent) {
return binder;
}
#Override
public boolean onUnbind(Intent intent) {
close();
return super.onUnbind(intent);
}
public boolean initialize() {
if(bluetoothManager == null) {
bluetoothManager = (BluetoothManager)getSystemService(Context.BLUETOOTH_SERVICE);
if(bluetoothManager == null) {
Log.e(TAG,"CANNOT INITIALIZE BLUETOOTH");
return false;
}
}bluetoothAdapter = bluetoothManager.getAdapter();
if(bluetoothAdapter == null) {
Log.e(TAG,"CANNOT FIND AN ADAPTER");
return false;
}return true;
}
public boolean connect(final String address) {
Log.w(TAG,"CONNECT PROCESS INITIALIZED");
if(bluetoothAdapter == null || address == null) {
Log.e(TAG,"ADAPTER NOT INITIALIZED");
return false;
}
//previously connected device, attempt to reconnect
if(deviceAddress != null && deviceAddress.equals(address)
&&bluetoothGatt != null) {
Log.d(TAG, "TRYING TO USE EXISTING GATT");
if(bluetoothGatt.connect()) {
connectionState = STATE_CONNECTING;
bluetoothGatt.connect();
return true;
} else
return false;
}
final BluetoothDevice device = bluetoothAdapter.getRemoteDevice(address);
if(device == null) {
Log.e(TAG, "DEVICE NOT FOUND");
return false;
}
bluetoothGatt = device.connectGatt(this, false, gattCallback);
deviceAddress = address;
connectionState = STATE_CONNECTING;
return true;
}
public void disconnect() {
if(bluetoothAdapter == null || bluetoothGatt == null) {
Log.w(TAG, "BLUETOOTH NOT INITIALIZED");
return;
}
bluetoothGatt.disconnect();
}
public void close() {
if(bluetoothGatt == null)
return;
bluetoothGatt.close();
bluetoothGatt = null;
}
public class LocalBinder extends Binder {
DeviceService getService() {
return DeviceService.this;
}
}
private final BluetoothGattCallback gattCallback = new BluetoothGattCallback() {
#Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
String intentAction;
if(newState == BluetoothProfile.STATE_CONNECTED) {
intentAction = ACTION_GATT_CONNECTED;
connectionState = STATE_CONNECTED;
broadcastUpdate(intentAction);
Log.i(TAG,"CONNECTED TO GATT SERVER!");
bluetoothGatt.discoverServices();
} else if(newState == BluetoothProfile.STATE_DISCONNECTED) {
intentAction = ACTION_GATT_DISCONNECTED;
connectionState = STATE_DISCONNECTED;
Log.i(TAG,"DISCONNECTED FROM GATT SERVER");
broadcastUpdate(intentAction);
}
}
#Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
Log.e(TAG,"STATUS: " + String.valueOf(status));
if (status == BluetoothGatt.GATT_SUCCESS)
broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
}
#Override
public void onCharacteristicRead(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic,
int status) {
if (status == BluetoothGatt.GATT_SUCCESS)
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
#Override
public void onCharacteristicChanged(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic) {
Log.e(TAG,"CHAR CHANGED \n" + gatt.toString() + "\n" + characteristic.getUuid().toString() + "\n");
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
#Override
public void onCharacteristicWrite(BluetoothGatt gatt,
BluetoothGattCharacteristic characteristic,
int status) {
Log.e(TAG,"CHAR WROTE" + gatt.toString() + "\n" + characteristic.getUuid().toString() + "\n");
if(status == BluetoothGatt.GATT_SUCCESS)
broadcastUpdate(ACTION_DATA_WRITE, characteristic);
}
};
public void readCharacteristic(BluetoothGattCharacteristic characteristic) {
if(bluetoothAdapter == null || bluetoothGatt == null) {
Log.e(TAG, "ADAPTER NOT INITIALIZED");
return;
}
bluetoothGatt.readCharacteristic(characteristic);
}
public void writeCharacteristic(BluetoothGattCharacteristic characteristic, byte[] value) {
if(bluetoothAdapter == null || bluetoothGatt == null) {
Log.e(TAG, "ADAPTER NOT INITIALIZED");
return;
}
characteristic.setValue(value);
characteristic.setWriteType(BluetoothGattCharacteristic.WRITE_TYPE_NO_RESPONSE);
bluetoothGatt.writeCharacteristic(characteristic);
System.out.println("Write value: " + value[0] + " on UUID: " + characteristic.getUuid().toString());
}
public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic,
boolean enabled) {
if(bluetoothAdapter == null || bluetoothGatt == null) return;
bluetoothGatt.setCharacteristicNotification(characteristic, enabled);
if(GattUUIDs.containsUuid(characteristic.getUuid())) {
BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
UUID.fromString(GattAttributes.CLIENT_CHARACTERISTIC_CONFIG));
// BluetoothGattDescriptor descriptor = new BluetoothGattDescriptor(
// GattUUIDs.UUID_CLIENT_CHAR_CONFIG, BluetoothGattDescriptor.PERMISSION_WRITE |
// BluetoothGattDescriptor.PERMISSION_READ);
descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
bluetoothGatt.writeDescriptor(descriptor);
}
}
public void setCharacteristicIndication(BluetoothGattCharacteristic characteristic,
boolean enabled) {
if(bluetoothAdapter ==null || bluetoothGatt == null) return;
BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
UUID.fromString(GattAttributes.CLIENT_CHARACTERISTIC_CONFIG));
descriptor.setValue(BluetoothGattDescriptor.ENABLE_INDICATION_VALUE);
bluetoothGatt.writeDescriptor(descriptor);
bluetoothGatt.setCharacteristicNotification(characteristic, enabled);
}
private void broadcastUpdate(final String action) {
final Intent intent = new Intent(action);
sendBroadcast(intent);
}
private void broadcastUpdate(final String action,
final BluetoothGattCharacteristic characteristic) {
final Intent intent = new Intent(action);
final UUID uuid = characteristic.getUuid();
Log.w(TAG,"BROADCAST UPDATE WITH ACTION: " + action);
if(GattUUIDs.containsUuid(uuid)) {
Log.e(TAG,"PASSOU AQUI");
int flag = characteristic.getProperties();
int format;
if((flag & 0x01) != 0)
format = BluetoothGattCharacteristic.FORMAT_UINT16;
else
format = BluetoothGattCharacteristic.FORMAT_UINT8;
byte[] data = characteristic.getValue();
if (GattUUIDs.UUID_IR_TEMPERATURE_MEASUREMENT.equals(uuid)) {
float objectTemperature = ((((float)data[1] * 256 + (float)data[0]) / (float)4)) * (float)0.03125;
float ambientTemperature = ((((float)data[3] * 256 + (float)data[2]) / (float)4)) * (float)0.03125;
// final int temp_data = characteristic.getIntValue(format, 1);
intent.putExtra(EXTRA_DATA, String.format("%.2f %.2f", objectTemperature, ambientTemperature));
} else if (GattUUIDs.UUID_IR_TEMPERATURE_CONFIG.equals(uuid)) {
if (data[0] == 0)
intent.putExtra(EXTRA_DATA, "IR DISABLED");
else
intent.putExtra(EXTRA_DATA, "IR ENABLED");
} else if (GattUUIDs.UUID_IR_TEMPERATURE_PERIOD.equals(uuid))
intent.putExtra(EXTRA_DATA, String.format("%d",data[0]*10));
else if (GattUUIDs.UUID_OPTICAL_MEASUREMENT.equals(uuid)) {
int m = (data[1] * 256 + data[0]) & 0x0FFF;
int e = ((data[1] * 256 + data[0]) & 0xF000) >> 12;
double lux = m * 0.01 * Math.pow(2.0,e);
intent.putExtra(EXTRA_DATA, String.format("%.2f",lux));
} else if (GattUUIDs.UUID_OPTICAL_CONFIG.equals(uuid)) {
if(data[0] == 0)
intent.putExtra(EXTRA_DATA, "OPTICAL DISABLED");
else
intent.putExtra(EXTRA_DATA, "OPTICAL ENABLED");
} else if (GattUUIDs.UUID_OPTICAL_PERIOD.equals(uuid))
intent.putExtra(EXTRA_DATA, String.format("%d",data[0] * 10));
else if (GattUUIDs.UUID_MOVEMENT_MEASUREMENT.equals(uuid))
intent.putExtra(EXTRA_DATA, String.format("%d %d %d %d %d %d %d %d %d",
(data[0] + data[1]*256),
(data[2] + data[3]*256),
(data[4] + data[5]*256),
(data[6] + data[7]*256),
(data[8] + data[9]*256),
(data[10] + data[11]*256),
(data[12] + data[13]*256),
(data[14] + data[15]*256),
(data[16] + data[17]*256)));
else if (GattUUIDs.UUID_MOVEMENT_CONFIG.equals(uuid)) {
if (data[0] == 0)
intent.putExtra(EXTRA_DATA, "MOVEMENT DISABLED");
else
intent.putExtra(EXTRA_DATA, "MOVEMENT ENABLEd");
} else if (GattUUIDs.UUID_MOVEMENT_PERIOD.equals(uuid))
intent.putExtra(EXTRA_DATA, String.format("%d",data[0] * 10));
else {
if (data != null && data.length > 0) {
final StringBuilder stringBuilder = new StringBuilder(data.length);
for(byte byteChar : data)
stringBuilder.append(String.format("%02X ",byteChar));
intent.putExtra(EXTRA_DATA, new String(data) + "\n" + stringBuilder.toString());
}
}
}
sendBroadcast(intent);
}
public List<BluetoothGattService> getSupportedGattServices() {
if(bluetoothGatt == null) return null;
return bluetoothGatt.getServices();
}
}
and this is my device control:
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattService;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.CompoundButton;
import android.widget.Switch;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.UUID;
/**
* Created by alan on 2/23/16.
*/
public class DeviceControl extends AppCompatActivity {
private final String TAG = DeviceControl.class.getSimpleName();
private ArrayList<ArrayList<BluetoothGattCharacteristic>> mGattCharacterics = new ArrayList<>();
private BluetoothGattCharacteristic bluetoothGattCharacteristic;
public static String ADDRESS;
private DeviceService deviceService;
private boolean connected = false;
private TextView dataText;
private Switch temperatureSwitch,
movementSwitch,
opticalSwitch;
private final String LIST_NAME = "NAME";
private final String LIST_UUID = "UUID";
private final ServiceConnection serviceConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
Log.e(TAG,"ONSERVICECONNECTED");
deviceService = ((DeviceService.LocalBinder)service).getService();
if(!deviceService.initialize())
finish();
deviceService.connect(ADDRESS);
}
#Override
public void onServiceDisconnected(ComponentName name) {
deviceService = null;
}
};
#Override
public void onCreate(Bundle savedInstanceBundle) {
super.onCreate(savedInstanceBundle);
setContentView(R.layout.activity_device_control);
dataText = (TextView)findViewById(R.id.dataText);
temperatureSwitch = (Switch)findViewById(R.id.temperatureSwitch);
movementSwitch = (Switch)findViewById(R.id.movementSwitch);
opticalSwitch = (Switch)findViewById(R.id.opticalSwitch);
temperatureSwitch.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked && connected)
writeCharacteristic(GattUUIDs.UUID_IR_TEMPERATURE_CONFIG, true);
else if(!isChecked && connected)
writeCharacteristic(GattUUIDs.UUID_IR_TEMPERATURE_CONFIG, false);
}
});
Bundle extras = getIntent().getExtras();
if(extras != null) {
setTitle(extras.getString("title"));
ADDRESS = extras.getString("address");
Intent intent = new Intent(this, DeviceService.class);
bindService(intent, serviceConnection, BIND_AUTO_CREATE);
}
registerReceiver(broadcastReceiver, makeIntentFilter());
}
public void writeCharacteristic(UUID toFind, boolean read) {
BluetoothGattCharacteristic gattCharacteristic = null;
byte[] enable = {(byte)0x01},
disable = {(byte)0x00};
for(int i = 0; i < mGattCharacterics.size(); i++) {
for(int j = 0; j < mGattCharacterics.get(i).size(); j++) {
if(mGattCharacterics.get(i).get(j).getUuid().equals(toFind))
gattCharacteristic = mGattCharacterics.get(i).get(j);
}
}
if(gattCharacteristic != null) {
if(read)
deviceService.writeCharacteristic(gattCharacteristic, enable);
else
deviceService.writeCharacteristic(gattCharacteristic, disable);
deviceService.setCharacteristicNotification(gattCharacteristic, true);
} else
Log.e(TAG,"NOTHING FOUND");
}
#Override
protected void onResume() {
super.onResume();
registerReceiver(broadcastReceiver, makeIntentFilter());
Log.w(TAG,"REGISTER RECEIVER");
if (deviceService != null) {
final boolean result = deviceService.connect(ADDRESS);
Log.d(TAG,"CONNECT RESULT = " + result);
}
}
#Override
protected void onPause() {
super.onPause();
unregisterReceiver(broadcastReceiver);
}
#Override
public void onBackPressed() {
super.onBackPressed();
deviceService.disconnect();
}
#Override
protected void onDestroy() {
super.onDestroy();
unbindService(serviceConnection);
deviceService = null;
}
private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
Log.e(TAG,"BROADCAST ACTION"+action);
switch (action) {
case DeviceService.ACTION_GATT_CONNECTED:
connected = true;
break;
case DeviceService.ACTION_GATT_DISCONNECTED:
connected = false;
break;
case DeviceService.ACTION_GATT_SERVICES_DISCOVERED:
getGattServices(deviceService.getSupportedGattServices());
break;
case DeviceService.ACTION_DATA_AVAILABLE:
displayData(intent.getStringExtra(DeviceService.EXTRA_DATA));
}
}
};
private void displayData(String data) {
if(data != null)
dataText.setText(data);
}
private void getGattServices(List<BluetoothGattService> gattServices) {
if(gattServices == null) return;
String uuid = null;
ArrayList<HashMap<String, String>> gattServiceData = new ArrayList<>();
ArrayList<ArrayList<HashMap<String, String>>> gattCharacteristicData
= new ArrayList<>();
mGattCharacterics = new ArrayList<>();
for (BluetoothGattService gattService : gattServices) {
HashMap<String, String> currentServiceData = new HashMap<>();
uuid = gattService.getUuid().toString();
currentServiceData.put(LIST_NAME, GattAttributes.lookup(uuid, "UnknownService"));
currentServiceData.put(LIST_UUID, uuid);
gattServiceData.add(currentServiceData);
ArrayList<HashMap<String, String>> gattCharacteristicGroupData = new ArrayList<>();
List<BluetoothGattCharacteristic> gattCharacteristics = gattService.getCharacteristics();
ArrayList<BluetoothGattCharacteristic> charas = new ArrayList<>();
for(BluetoothGattCharacteristic gattCharacteristic : gattCharacteristics) {
charas.add(gattCharacteristic);
HashMap<String, String> currentCharaData = new HashMap<>();
uuid = gattCharacteristic.getUuid().toString();
currentCharaData.put(LIST_NAME, GattAttributes.lookup(uuid, "UnknownCharacteristic"));
currentCharaData.put(LIST_UUID, uuid);
gattCharacteristicGroupData.add(currentCharaData);
//System.out.println("GATTCHAR\n\n" + gattCharacteristic.toString()+"\n");
}
mGattCharacterics.add(charas);
gattCharacteristicData.add(gattCharacteristicGroupData);
}
}
private static IntentFilter makeIntentFilter() {
final IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(DeviceService.ACTION_GATT_CONNECTED);
intentFilter.addAction(DeviceService.ACTION_GATT_DISCONNECTED);
intentFilter.addAction(DeviceService.ACTION_GATT_SERVICES_DISCOVERED);
intentFilter.addAction(DeviceService.ACTION_DATA_AVAILABLE);
return intentFilter;
}
}
Thanks for your attention.

How to Scan the BLE device in background service without library?

I am trying to connect BLE device with android application. I am getting the device name,Mac Address and rssi value in foreground. I dont know how to scan the device in background and get the details of that particular device like MAC address,rssi value.

You have to do all in the background for that start sticky service and in onStartCommand of that services start scanning.
package com.myapp.services;
import java.util.List;
import android.annotation.TargetApi;
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.content.pm.PackageManager;
import android.os.Build;
import android.os.Handler;
import android.os.IBinder;
import android.os.Looper;
import android.preference.PreferenceManager;
import android.support.v4.content.LocalBroadcastManager;
import android.text.TextUtils;
import android.widget.Toast;
import com.myapp.R;
/**Both RX and RSSI (Received Signal Strength Indication) are indications of the power level being received
* by an antenna
* The difference between RX and RSSI is that RX is measured in milliWatts (mW) or decibel-milliwatts (dBm)
* whereas RSSI is a signal strength percentage—the higher the RSSI number, the stronger the signal
*
*/
#TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR2)
public class BeaconService extends Service implements BluetoothAdapter.LeScanCallback{
private static final String TAG = BeaconService.class.getSimpleName();
private BluetoothGatt btGatt;
private BluetoothAdapter mBluetoothAdapter;
#Override
public void onCreate() {
super.onCreate();
writeLine("Automate service created...");
getBTService();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
writeLine("Automate service start...");
if (!isBluetoothSupported()) {
Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
stopSelf();
}else{
if(mBluetoothAdapter!=null && mBluetoothAdapter.isEnabled()){
startBLEscan();
}else{
stopSelf();
}
}
return START_STICKY;
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public void onDestroy() {
writeLine("Automate service destroyed...");
stopBLEscan();
super.onDestroy();
if(btGatt!=null){
btGatt.disconnect();
btGatt.close();
btGatt = null;
}
}
#Override
public boolean stopService(Intent name) {
writeLine("Automate service stop...");
stopSelf();
return super.stopService(name);
}
// Initializes a Bluetooth adapter. For API level 18 and above, get a reference to
// BluetoothAdapter through BluetoothManager.
public BluetoothAdapter getBTService(){
BluetoothManager btManager = (BluetoothManager) getApplicationContext().getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = (BluetoothAdapter) btManager.getAdapter();
return mBluetoothAdapter;
}
public boolean isBluetoothSupported() {
return this.getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE);
}
public void startBLEscan(){
mBluetoothAdapter.startLeScan(this);
}
public void stopBLEscan(){
mBluetoothAdapter.stopLeScan(this);
}
/**
*
* #param enable
*/
public void scanLeDevice(final boolean enable) {
if (enable) {
startBLEscan();
} else {
stopBLEscan();
}
}
public static void enableDisableBluetooth(boolean enable){
BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter != null) {
if(enable) {
bluetoothAdapter.enable();
}else{
bluetoothAdapter.disable();
}
}
}
#Override
public void onLeScan(final BluetoothDevice device, final int rssi, byte[] scanRecord) {
if(device!=null && device.getName()!=null){
//Log.d(TAG + " onLeScan: ", "Name: "+device.getName() + "Address: "+device.getAddress()+ "RSSI: "+rssi);
if(rssi > -90 && rssi <-1){
writeLine("Automate service BLE device in range: "+ device.getName()+ " "+rssi);
if (device.getName().equalsIgnoreCase("NCS_Beacon") || device.getName().equalsIgnoreCase("estimote")) {
//This Main looper thread is main for connect gatt, don't remove it
// Although you need to pass an appropriate context getApplicationContext(),
//Here if you use Looper.getMainLooper() it will stop getting callback and give internal exception fail to register //callback
new Handler(getApplicationContext().getMainLooper()).post(new Runnable() {
#Override
public void run() {
btGatt = device.connectGatt(getApplicationContext(), false, bleGattCallback);
Log.e(TAG, "onLeScan btGatt value returning from connectGatt "+btGatt);
}
});
}
stopBLEscan();
}else{
//Log.v("Device Scan Activity", device.getAddress()+" "+"BT device is still too far - not connecting");
}
}
}
BluetoothGattCallback bleGattCallback = new BluetoothGattCallback() {
#Override
public void onConnectionStateChange(final BluetoothGatt gatt, int status, int newState) {
super.onConnectionStateChange(gatt, status, newState);
writeLine("Automate service connection state: "+ newState);
if (newState == android.bluetooth.BluetoothProfile.STATE_CONNECTED){
writeLine("Automate service connection state: STATE_CONNECTED");
Log.v("BLEService", "BLE Connected now discover services");
Log.v("BLEService", "BLE Connected");
new Thread(new Runnable() {
#Override
public void run() {
writeLine("Automate service go for discover services");
gatt.discoverServices();
}
}).start();
}else if (newState == android.bluetooth.BluetoothProfile.STATE_DISCONNECTED){
writeLine("Automate service connection state: STATE_DISCONNECTED");
Log.v("BLEService", "BLE Disconnected");
}
}
#Override
public void onServicesDiscovered(final BluetoothGatt gatt, int status) {
super.onServicesDiscovered(gatt, status);
if (status == BluetoothGatt.GATT_SUCCESS) {
writeLine("Automate service discover service: GATT_SUCCESS");
Log.v("BLEService", "BLE Services onServicesDiscovered");
//Get service
List<BluetoothGattService> services = gatt.getServices();
writeLine("Automate service discover service imei: " +imei);
}
}
#Override
public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
super.onCharacteristicRead(gatt, characteristic, status);
}
#Override
public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
super.onCharacteristicChanged(gatt, characteristic);
}
};
private void writeLine(final String message) {
Handler h = new Handler(getApplicationContext().getMainLooper());
// Although you need to pass an appropriate context
h.post(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),message,Toast.LENGTH_SHORT).show();
}
});
}
}
In manifest.xml
<uses-feature
android:name="android.hardware.bluetooth_le"
android:required="true" />
<!-- Permission for bluetooth -->
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<service
android:name="com.myapp.services.BeaconService"
android:enabled="true"
android:exported="false" />

Use service to scan and connect ble devices when application is in background in android.
package com.example.tracker.service;
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.le.BluetoothLeScanner;
import android.bluetooth.le.ScanFilter;
import android.bluetooth.le.ScanSettings;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.ServiceConnection;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Handler;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.support.v4.widget.SwipeRefreshLayout;
import android.util.Log;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.SeekBar;
import android.widget.Toast;
import com.google.firebase.auth.FirebaseAuth;
import com.example.tracker.R;
import com.example.tracker.utils.SampleGattAttributes;
import com.example.tracker.utils.SharedPreferencesUtils;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.UUID;
import static com.example.tracker.constant.SharedFreferencesConstant.KEY_SP_MOBILE_NUMBER;
/**
* Created by Jprashant on 12/9/17.
*/
public class BackgroundService extends Service{
private int scanPeriod;
Context context;
String TAG="BackgroundService";
private BluetoothAdapter mBluetoothAdapter;
private boolean mScanning;
private Handler mHandler;
public String[] advDataTypes = new String[256];
ArrayList<BluetoothDevice> bluetoothDeviceArrayList=new ArrayList<>();
ArrayList<BluetoothDevice> bluetoothDeviceArrayListTwo=new ArrayList<>();
private static final int REQUEST_ENABLE_BT = 1;
// Stops scanning after 10 seconds.
private static final long SCAN_PERIOD = 10000;
/*Connect Ble Device*/
String deviceId;
public static String arrayDidOpnSec2;
BluetoothGattService gattService4;
public static ArrayList<BluetoothGattCharacteristic> lastCharacteristic;
// AlertDialog.Builder alertDialog;
private float avgRssi = 0.0f;
// private Dialog dialog;
private BluetoothLeService mBluetoothLeService;
private boolean mConnected = false;
private ArrayList<ArrayList<BluetoothGattCharacteristic>> mGattCharacteristics = new ArrayList();
//service and char uuid
private static final int TRACKER_ON_OFF = 2;
private static final UUID TRACER_TRIPPLE_PRESS_SERVICE=UUID.fromString("edfec62e-9910-0bac-5241-d8bda6932a2f");
private static final UUID TRACKER_TRIPPLE_PRESS_CHAR=UUID.fromString("772ae377-b3d2-4f8e-4042-5481d1e0098c");
private static final UUID IMMEDIATE_ALERT_UUID = UUID.fromString("00001802-0000-1000-8000-00805f9b34fb");
private static final UUID ALERT_LEVEL_UUID = UUID.fromString("00002a06-0000-1000-8000-00805f9b34fb");
private Button btnSMS;
public static String mDeviceName,mDeviceAddress,connectionStatus;
/*-------------------------------------------------------------------------------*/
public static final String PREFS_NAME = "PreferencesFile";
public int deviceCount = 0;
public String[] mData = new String[400];
private Handler mHandler1;
private ListView listItems;
/*--------for > 21--------------*/
private BluetoothLeScanner mLEScanner;
private ScanSettings settings;
private List<ScanFilter> filters;
private BluetoothGatt mGatt;
public BackgroundService() {
}
public BackgroundService(Context context) {
this.context = context;
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
// getting systems default ringtone
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
Toast.makeText(getApplicationContext(),"CALL YOUR METHOD",Toast.LENGTH_LONG).show();
mHandler = new Handler();
// Use this check to determine whether BLE is supported on the device. Then you can
// selectively disable BLE-related features.
if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
Toast.makeText(context, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
}
// Initializes a Bluetooth adapter. For API level 18 and above, get a reference to
// BluetoothAdapter through BluetoothManager.
final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = bluetoothManager.getAdapter();
// Checks if Bluetooth is supported on the device.
if (mBluetoothAdapter == null) {
Toast.makeText(context, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
return;
}
for (int i = 0; i < 256; i += REQUEST_ENABLE_BT) {
advDataTypes[i] = "Unknown Data Type";
}
advDataTypes[REQUEST_ENABLE_BT] = "Flags";
advDataTypes[2] = "Incomplete List of 16-bit Service Class UUIDs";
advDataTypes[3] = "Complete List of 16-bit Service Class UUIDs";
advDataTypes[4] = "Incomplete List of 32-bit Service Class UUIDs";
advDataTypes[5] = "Complete List of 32-bit Service Class UUIDs";
advDataTypes[6] = "Incomplete List of 128-bit Service Class UUIDs";
advDataTypes[7] = "Complete List of 128-bit Service Class UUIDs";
advDataTypes[8] = "Shortened Local Name";
advDataTypes[9] = "Complete Local Name";
advDataTypes[10] = "Tx Power Level";
advDataTypes[13] = "Class of LocalDevice";
advDataTypes[14] = "Simple Pairing Hash";
advDataTypes[15] = "Simple Pairing Randomizer R";
advDataTypes[16] = "LocalDevice ID";
advDataTypes[17] = "Security Manager Out of Band Flags";
advDataTypes[18] = "Slave Connection Interval Range";
advDataTypes[20] = "List of 16-bit Solicitaion UUIDs";
advDataTypes[21] = "List of 128-bit Solicitaion UUIDs";
advDataTypes[22] = "Service Data";
advDataTypes[23] = "Public Target Address";
advDataTypes[24] = "Random Target Address";
advDataTypes[25] = "Appearance";
advDataTypes[26] = "Advertising Interval";
advDataTypes[61] = "3D Information Data";
advDataTypes[255] = "Manufacturer Specific Data";
scanPeriod = getApplicationContext().getSharedPreferences(PREFS_NAME, 0).getInt("scan_interval", 6000);
scanTrackerDevices();
}
}, 10000);
return START_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
}
public void scanTrackerDevices(){
Log.e(TAG,"scanTrackerDevices");
if (!mBluetoothAdapter.isEnabled()) {
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
}
}
scanLeDevice(true);
}
private void scanLeDevice(final boolean enable) {
bluetoothDeviceArrayList.clear();
if (enable) {
// Stops scanning after a pre-defined scan period.
mHandler.postDelayed(new Runnable() {
#Override
public void run() {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
int arraySize=bluetoothDeviceArrayListTwo.size();
Log.e(TAG,"bluetoothDeviceArrayListTwo Size in scan :"+arraySize);
for (int i=0;i<bluetoothDeviceArrayListTwo.size();i++){
BluetoothDevice bluetoothDevice=bluetoothDeviceArrayListTwo.get(i);
Log.e(TAG,"Device Name in scan :"+bluetoothDevice.getName());
Log.e(TAG,"Device Address in scan :"+bluetoothDevice.getAddress());
if (i==0){
mBluetoothLeService.connect(bluetoothDevice.getAddress());
}
}
}
}, scanPeriod);
mScanning = true;
mBluetoothAdapter.startLeScan(mLeScanCallback);
} else {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
}
}
private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() {
public void onLeScan(final BluetoothDevice device, final int rssi, final byte[] scanRecord) {
String d = "";
String rd = "";
String h = "0123456789ABCDEF";
int ln = 0;
int i = 0;
while (i < scanRecord.length) {
int x = scanRecord[i] & 255;
rd = new StringBuilder(String.valueOf(rd)).append(h.substring(x / 16, (x / 16) + REQUEST_ENABLE_BT)).append(h.substring(x % 16, (x % 16) +REQUEST_ENABLE_BT)).toString();
if (i == ln) {
ln = (i + x) + REQUEST_ENABLE_BT;
if (x == 0) {
break;
}
d = new StringBuilder(String.valueOf(d)).append("\r\n Length: ").append(h.substring(x / 16, (x / 16) + REQUEST_ENABLE_BT)).append(h.substring(x % 16, (x % 16) +REQUEST_ENABLE_BT)).toString();
i += REQUEST_ENABLE_BT;
x = scanRecord[i] & 255;
d = new StringBuilder(String.valueOf(d)).append(", Type :").append(h.substring(x / 16, (x / 16) + REQUEST_ENABLE_BT)).append(h.substring(x % 16, (x % 16) + REQUEST_ENABLE_BT)).append(" = ").append(advDataTypes[x]).append(", Value: ").toString();
rd = new StringBuilder(String.valueOf(rd)).append(h.substring(x / 16, (x / 16) + REQUEST_ENABLE_BT)).append(h.substring(x % 16, (x % 16) + REQUEST_ENABLE_BT)).toString();
} else {
d = new StringBuilder(String.valueOf(d)).append(" ").append(h.substring(x / 16, (x / 16) + REQUEST_ENABLE_BT)).append(h.substring(x % 16, (x % 16) +REQUEST_ENABLE_BT)).toString();
}
i += REQUEST_ENABLE_BT;
}
Log.e(TAG,"UUID : "+device.getUuids());
String[] arrayDeviceName=String.valueOf(device.getName()).split(" ");
String deviceName0=arrayDeviceName[0];
bluetoothDeviceArrayListTwo.add(device);
}
};
/*-------------------Connect BLE---------------------------------------------*/
private Handler mHandler2;
public final BroadcastReceiver mGattUpdateReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent)
{
String action = intent.getAction();
if (BluetoothLeService.ACTION_GATT_CONNECTED.equals(action))
{
numberOfRssi = 0;
avgRssi = 0.0f;
mConnected = true;
updateConnectionState(R.string.connected);
mHandler2.postDelayed(startRssi, 300);
Log.e(TAG,"ACTION_GATT_CONNECTED");
}
else if (BluetoothLeService.ACTION_GATT_DISCONNECTED.equals(action)) {
mConnected = false;
updateConnectionState(R.string.disconnected);
Log.e(TAG,"ACTION_GATT_DISCONNECTED");
} else if (BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED.equals(action)) {
displayGattServicesForDimmer(mBluetoothLeService.getSupportedGattServices());// For dimmer
Log.e(TAG,"ACTION_GATT_SERVICES_DISCOVERED");
} else if (BluetoothLeService.ACTION_DATA_AVAILABLE.equals(action)) {
Log.e(TAG,"ACTION_DATA_AVAILABLE");
String unknownServiceString = context.getResources().getString(R.string.unknown_service);
displayDimmerData("<<" + SampleGattAttributes.lookup(intent.getStringExtra(BluetoothLeService.CHARACTERISTIC_UUID), unknownServiceString) + ">> Value: " + intent.getStringExtra(BluetoothLeService.EXTRA_DATA) + "]");
displayDimmer2(intent.getStringExtra(BluetoothLeService.EXTRA_DATA));
} else if (BluetoothLeService.ACTION_GATT_RSSI_UPDATE.equals(action)) {
updateRssi(intent.getIntExtra(BluetoothLeService.EXTRA_DATA, -400));
} else if (BluetoothLeService.ACTION_GATT_WRITE_FAILED.equals(action)) {
Log.e(TAG,"ACTION_GATT_WRITE_FAILED");
}
}
};
/*------------------------------------------------------------------------*/
#Override
public void onCreate() {
super.onCreate();
// -------------------Connect Ble--------------------------------------
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(BluetoothLeService.ACTION_GATT_CONNECTED);
intentFilter.addAction(BluetoothLeService.ACTION_GATT_DISCONNECTED);
intentFilter.addAction(BluetoothLeService.ACTION_GATT_SERVICES_DISCOVERED);
intentFilter.addAction(BluetoothLeService.ACTION_DATA_AVAILABLE);
intentFilter.addAction(BluetoothLeService.ACTION_GATT_RSSI_UPDATE);
intentFilter.addAction(BluetoothLeService.ACTION_GATT_WRITE_FAILED);
Log.e(TAG,"OnResume()");
getApplicationContext().registerReceiver(mGattUpdateReceiver, intentFilter);
getApplicationContext().bindService(new Intent(getApplicationContext(), BluetoothLeService.class), mServiceConnection, 1);
mHandler2=new Handler();
}
private BluetoothGattCharacteristic mNotifyCharacteristic;
private final ServiceConnection mServiceConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName componentName, IBinder service) {
mBluetoothLeService = ((BluetoothLeService.LocalBinder) service).getService();
if (!mBluetoothLeService.initialize()) {
Log.e(TAG, "Unable to initialize Bluetooth");
}
}
public void onServiceDisconnected(ComponentName componentName) {
mBluetoothLeService = null;
}
};
private boolean notificationActive = true;
private int numberOfRssi = 0;
private Runnable startRssi = new Runnable() {
public void run() {
if (mConnected) {
mBluetoothLeService.readRemoteRssi();
mHandler2.postDelayed(startRssi, 200);
}
}
};
public BluetoothGatt getmGatt() {
return mGatt;
}
//code from DeviceControlActivity
private void updateConnectionState(final int resourceId) {
connectionStatus= String.valueOf(resourceId);
Log.e(TAG,"Resource ID"+resourceId);
}
private void displayDimmerData(String data){
Log.e(TAG,"Display Data :"+data);
}
private void displayDimmer2(String data){
Log.e(TAG,"display Dimmer2"+data);
String sosString = data.substring(0, Math.min(data.length(), 3));
Log.e(TAG,"SOS String :"+sosString);
if (sosString.equals("SOS")){
Intent callIntent = new Intent(Intent.ACTION_CALL);
callIntent.setData(Uri.parse("tel:"+ SharedPreferencesUtils.getStringFromSharedPreferences(KEY_SP_MOBILE_NUMBER,getApplicationContext())));
callIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
getApplicationContext().startActivity(callIntent);
}
}
private void updateRssi(int data) {
if (data > -400) {
if (this.numberOfRssi > 10) {
this.avgRssi = ((9.0f * this.avgRssi) + ((float) data)) / 10.0f;
} else {
this.avgRssi = (this.avgRssi + ((float) data)) / 2.0f;
this.numberOfRssi++;
}
connectionStatus="Connected, RSSI:" + data + ", Avg:" + Math.round(this.avgRssi);
}
}
/*-------------------------disaplay gatt service for dimmer----------------------*/
private void displayGattServicesForDimmer(List<BluetoothGattService> gattServices) {
if (gattServices != null) {
String unknownServiceString = getResources().getString(R.string.unknown_service);
String unknownCharaString = getResources().getString(R.string.unknown_characteristic);
ArrayList<HashMap<String, String>> gattServiceData = new ArrayList();
ArrayList<ArrayList<HashMap<String, String>>> gattCharacteristicData = new ArrayList();
this.mGattCharacteristics = new ArrayList();
for (BluetoothGattService gattService : gattServices) {
HashMap<String, String> currentServiceData = new HashMap();
String uuid = gattService.getUuid().toString();
currentServiceData.put("NAME", SampleGattAttributes.lookup(uuid, unknownServiceString));
currentServiceData.put("UUID", uuid);
gattServiceData.add(currentServiceData);
ArrayList<HashMap<String, String>> gattCharacteristicGroupData = new ArrayList();
List<BluetoothGattCharacteristic> gattCharacteristics = gattService.getCharacteristics();
ArrayList<BluetoothGattCharacteristic> charas = new ArrayList();
for (BluetoothGattCharacteristic gattCharacteristic : gattCharacteristics) {
charas.add(gattCharacteristic);
HashMap<String, String> currentCharaData = new HashMap();
uuid = gattCharacteristic.getUuid().toString();
currentCharaData.put("NAME", "\t\t\t<<" + SampleGattAttributes.lookup(uuid, unknownCharaString) + ">>");
currentCharaData.put("UUID", "\t\t\tUUID: 0x" + uuid.substring(4, 8) + ", Properties: " + translateProperties(gattCharacteristic.getProperties()));
gattCharacteristicGroupData.add(currentCharaData);
Log.i(TAG,"CUrrent CHARACTERISTIC DATA"+currentCharaData);
Log.i(TAG,"UUID : "+uuid.substring(4, 8));
Log.i(TAG,"Proprties : "+gattCharacteristic.getProperties());
Log.i(TAG,"Translate Proprties : "+translateProperties(gattCharacteristic.getProperties()));
Log.i(TAG,"char list"+gattCharacteristicData.toString());
}
gattService4=gattService;
this.mGattCharacteristics.add(charas);
}
if (mGattCharacteristics.get(3)!=null) {
lastCharacteristic = new ArrayList<>(mGattCharacteristics.get(3));
enableNotifyOfCharcteristicForDimmer(lastCharacteristic);
}
}
}
private String translateProperties(int properties) {
String s = "";
if ((properties & 1) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/Broadcast").toString();
}
if ((properties & 2) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/Read").toString();
}
if ((properties & 4) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/WriteWithoutResponse").toString();
}
if ((properties & 8) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/Write").toString();
}
if ((properties & 16) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/Notify").toString();
}
if ((properties & 32) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/Indicate").toString();
}
if ((properties & 64) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/SignedWrite").toString();
}
if ((properties & 128) > 0) {
s = new StringBuilder(String.valueOf(s)).append("/ExtendedProperties").toString();
}
if (s.length() > 1) {
return s.substring(1);
}
return s;
}
// Enable Characteristic for dimmer
public void enableNotifyOfCharcteristicForDimmer(ArrayList<BluetoothGattCharacteristic> lastCharacteristic){
if(mGattCharacteristics!=null) {
checkCharacteristicPresent(lastCharacteristic.get(0));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(0), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+0+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 0 +" :" +lastCharacteristic.get(0).toString());
checkCharacteristicPresent(lastCharacteristic.get(1));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(1), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+1+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 1 +" :" +lastCharacteristic.get(1).toString());
checkCharacteristicPresent(lastCharacteristic.get(2));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(2), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+2+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 2 +" :" +lastCharacteristic.get(2).toString());
checkCharacteristicPresent(lastCharacteristic.get(3));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(3), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+3+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 3 +" :" +lastCharacteristic.get(3).toString());
checkCharacteristicPresent(lastCharacteristic.get(4));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(4), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+4+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 4 +" :" +lastCharacteristic.get(4).toString());
checkCharacteristicPresent(lastCharacteristic.get(5));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(5), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+5+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 5 +" :" +lastCharacteristic.get(5).toString());
checkCharacteristicPresent(lastCharacteristic.get(2));
mBluetoothLeService.setCharacteristicNotification(lastCharacteristic.get(2), true);
notificationActive = true;
Log.e(TAG,"Characteristic index : "+2+":\nM GATT CHARACTERISTIC AT "+"Service 4 : CHAR"+ 2 +" :" +lastCharacteristic.get(2).toString());
}
}
// Check the type of characteristic i.e READ/WRITE/NOTIFY
public void checkCharacteristicPresent(BluetoothGattCharacteristic characteristic) {
int charaProp = characteristic.getProperties();
Log.e(TAG, "checkCharacteristicPresent Prop : " + charaProp);
mBluetoothLeService.setCurrentCharacteristic(characteristic);
if ((charaProp & 2) > 0) {
Log.e(TAG, "CharProp & 2 : " + charaProp);
mBluetoothLeService.readCharacteristic(characteristic);
}
if ((charaProp & 16) > 0) {
Log.e(TAG, "CharProp & 16 : " + charaProp);
mNotifyCharacteristic = characteristic;
} else {
if (mNotifyCharacteristic != null) {
mBluetoothLeService.setCharacteristicNotification(mNotifyCharacteristic, false);
mNotifyCharacteristic = null;
}
}
if ((charaProp & 8) > 0 || (charaProp & 4) > 0) {
Log.e(TAG, "CharProp & 4 : " + charaProp);
} else {
Log.e(TAG, "Else : " + charaProp);
}
}
}
Write this code in manifest.xml
<service android:name=".service.BackgroundService" />