This is a silly question, but I have a code which is giving me list of beacons with their names, addresses, uuids, majors and minors in TextView. I'm calculating uuid, major and minor values(in code below). And when I'm setting these three values into TextView they are swaping with other beacon values. So my question is, how do I set proper uuid, major and minor value to the proper beacon?
Link with the example: https://i.stack.imgur.com/vlepI.jpg
I have got two beacons. Names and adresses are correct, but as you can see uuid, major minor are the same and during scanning they keep swapping with each other beacon values.
Code is given below.
DeviceScanActivity
public class DeviceScanActivity extends ListActivity {
private LeDeviceListAdapter mLeDeviceListAdapter;
private BluetoothAdapter mBluetoothAdapter;
private boolean mScanning;
private Handler mHandler;
private static final int REQUEST_ENABLE_BT = 1;
private static final long SCAN_PERIOD = 10000;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getActionBar().setTitle(R.string.title_devices);
mHandler = new Handler();
if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
finish();
}
final BluetoothManager bluetoothManager =
(BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = bluetoothManager.getAdapter();
if (mBluetoothAdapter == null) {
Toast.makeText(this, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
finish();
return;
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menu_scan:
mLeDeviceListAdapter.clear();
scanLeDevice(true);
break;
case R.id.menu_stop:
scanLeDevice(false);
break;
}
return true;
}
@Override
protected void onResume() {
super.onResume();
if (!mBluetoothAdapter.isEnabled()) {
if (!mBluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
}
mLeDeviceListAdapter = new LeDeviceListAdapter();
setListAdapter(mLeDeviceListAdapter);
scanLeDevice(true);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// User chose not to enable Bluetooth.
if (requestCode == REQUEST_ENABLE_BT && resultCode == Activity.RESULT_CANCELED) {
finish();
return;
}
super.onActivityResult(requestCode, resultCode, data);
}
@Override
protected void onPause() {
super.onPause();
scanLeDevice(false);
mLeDeviceListAdapter.clear();
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
final BluetoothDevice device = mLeDeviceListAdapter.getDevice(position);
if (device == null) return;
//final Intent intent = new Intent(this, DeviceControlActivity.class);
if (mScanning) {
mBluetoothAdapter.stopLeScan(mLeScanCallback);
mScanning = false;
}
//startActivity(intent);
}
private void scanLeDevice(final boolean enable) {
if (enable) {
// Stops scanning after a pre-defined scan period.
mHandler.postDelayed(new Runnable() {
@Override
public void run() {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
invalidateOptionsMenu();
}
}, SCAN_PERIOD);
mScanning = true;
mBluetoothAdapter.startLeScan(mLeScanCallback);
} else {
mScanning = false;
mBluetoothAdapter.stopLeScan(mLeScanCallback);
}
invalidateOptionsMenu();
}
private class LeDeviceListAdapter extends BaseAdapter {
private ArrayList<BluetoothDevice> mLeDevices;
private LayoutInflater mInflator;
public LeDeviceListAdapter() {
super();
mLeDevices = new ArrayList<BluetoothDevice>();
mInflator = DeviceScanActivity.this.getLayoutInflater();
}
public void addDevice(BluetoothDevice device) {
if(!mLeDevices.contains(device)) {
mLeDevices.add(device);
}
}
public BluetoothDevice getDevice(int position) {
return mLeDevices.get(position);
}
public void clear() {
mLeDevices.clear();
}
@Override
public int getCount() {
return mLeDevices.size();
}
@Override
public Object getItem(int i) {
return mLeDevices.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
@Override
public View getView(int i, View view, ViewGroup viewGroup) {
ViewHolder viewHolder;
if (view == null) {
view = mInflator.inflate(R.layout.listitem_device, null);
viewHolder = new ViewHolder();
viewHolder.deviceAddress = (TextView) view.findViewById(R.id.device_address);
viewHolder.deviceName = (TextView) view.findViewById(R.id.device_name);
viewHolder.deviceUUID = (TextView) view.findViewById(R.id.device_uuid);
viewHolder.deviceMajor = (TextView) view.findViewById(R.id.device_major);
viewHolder.deviceMinor = (TextView) view.findViewById(R.id.device_minor);
view.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) view.getTag();
}
BluetoothDevice device = mLeDevices.get(i);
final String deviceName = device.getName();
if (deviceName != null && deviceName.length() > 0)
viewHolder.deviceName.setText(deviceName);
else
viewHolder.deviceName.setText(R.string.unknown_device);
viewHolder.deviceAddress.setText(device.getAddress());
viewHolder.deviceUUID.setText(uuid);
viewHolder.deviceMajor.setText(major);
viewHolder.deviceMinor.setText(minor);
return view;
}
}
public String uuid;
public int major_temp;
public int minor_temp;
public String major;
public String minor;
public static final char[] hexArray = "0123456789ABCDEF".toCharArray();
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);
}
public BluetoothAdapter.LeScanCallback mLeScanCallback =
new BluetoothAdapter.LeScanCallback() {
@Override
public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
runOnUiThread(new Runnable() {
@Override
public void run() {
mLeDeviceListAdapter.addDevice(device);
mLeDeviceListAdapter.notifyDataSetChanged();
}
});
int startByte = 2;
boolean patternFound = false;
while (startByte <= 5) {
if ( ((int) scanRecord[startByte + 2] & 0xff) == 0x02 && //Identifies an iBeacon
((int) scanRecord[startByte + 3] & 0xff) == 0x15) { //Identifies correct data length
patternFound = true;
break;
}
startByte++;
}
if (patternFound) {
byte[] uuidBytes = new byte[16];
System.arraycopy(scanRecord, startByte+4, uuidBytes, 0, 16);
String hexString = bytesToHex(uuidBytes);
//Here is your UUID
uuid = hexString.substring(0,8) + "-" +
hexString.substring(8,12) + "-" +
hexString.substring(12,16) + "-" +
hexString.substring(16,20) + "-" +
hexString.substring(20,32);
major_temp = (scanRecord[startByte+20] & 0xff) * 0x100 + (scanRecord[startByte+21] & 0xff);
major = Integer.toString(major_temp);
minor_temp = (scanRecord[startByte+22] & 0xff) * 0x100 + (scanRecord[startByte+23] & 0xff);
minor = Integer.toString(minor_temp);
// TextView textView1 = (TextView) findViewById(R.id.device_uuid);
// textView1.setText(uuid+" Major: " + major + " Minor: " + minor);
}
}
};
static class ViewHolder {
TextView deviceName;
TextView deviceAddress;
TextView deviceUUID;
TextView deviceMajor;
TextView deviceMinor;
}
}
And layout file:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView android:id="@+id/device_name"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="24dp"/>
<TextView android:id="@+id/device_address"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="12dp"/>
<TextView android:id="@+id/device_uuid"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="12dp"/>
<TextView android:id="@+id/device_major"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="12dp"/>
<TextView android:id="@+id/device_minor"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="12dp"/>
</LinearLayout>
