I am working with BLE connection in my app. I have a single class for the bluetooth functionalities and I am passing a command from a different fragment class for writing any value.
So based on the scenario, inside the fragment, on click of a button will send a write command to the bluetooth class. Its working fine in the first time and I am getting the response. But while clicking the button the button for the second time, onCharacteristicChanged() is called twice and the third time click makes it being called thrice and so on. I genuinely can't figure it out. I will post my code below. Please have a look. In case of any queries, please do let me know. Thanks in advance.
I am writing data inside the OnDescriptorWrite() where as recieving data inside onCharacteristicChanged().
Inside the fragment:
rvw_availableList.addOnItemTouchListener((
new RecyclerItemClickListener(myContext, new RecyclerItemClickListener.OnItemClickListener() {
@Override
public void onItemClick(View view, int position)
{
BluetoothDevice bl_device = al_deviceList.get(position);
bleUtil.writeData(bl_device,"3AxxxxxxD");
}
})
));
Now inside the writeData() of BleUtil Class:
public void writeData(BluetoothDevice bluetoothDevice, final String value)
{
BluetoothGattCallback gattCallback =
new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
gatt.discoverServices();
}
@Override
public void onServicesDiscovered(final BluetoothGatt gatt, final int status) {
activity.runOnUiThread(new Runnable() {
public void run() {
// prgd_progress.HideProgressDialog();
Log.d("onServicesDiscovered", "Service uuid ");
List<BluetoothGattService> gattServices = gatt.getServices();
Log.d("onServicesDiscovered", "Services count: "+gattServices.size());
for (BluetoothGattService gattService: gattServices)
{
Log.d("aniservice",gattService.getUuid().toString());
}
if (status == BluetoothGatt.GATT_SUCCESS) {
ArrayList<String> alst_uuid = new ArrayList<String>();
BluetoothGattCharacteristic characteristic =
gatt.getService(UUID.fromString(SERVICE_ID)).getCharacteristics().get(0);
Log.d("anicheck",characteristic.getUuid().toString());
Log.d("anicheck",characteristic.getDescriptors().get(0).getUuid().toString());
// BluetoothGattCharacteristic characteristic =
// gattServices.get(0).getCharacteristics().get(0);
// Log.d("foundoutchar",gattServices.get(0).getUuid()+" "+gattServices.get(0).getCharacteristics().get(0).getUuid()+"");
gatt.setCharacteristicNotification(characteristic,true);
for (BluetoothGattDescriptor descriptor:characteristic.getDescriptors()){
Log.e("anicheck", "BluetoothGattDescriptor: "+descriptor.getUuid().toString());
}
final BluetoothGattDescriptor descriptor = characteristic.getDescriptor(UUID.fromString("00002902-0000-1000-8000-00805f9b34fb"));
if(descriptor!= null)
{
descriptor.setValue(
BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
gatt.writeDescriptor(descriptor);
}
else
{
Toast.makeText(activity,"nullval", Toast.LENGTH_SHORT).show();
}
// Log.d("foundoutchar", descriptor.getUuid().toString());
}
}
});
}
@Override
public void onCharacteristicWrite(final BluetoothGatt gatt, final BluetoothGattCharacteristic characteristic, final int status) {
super.onCharacteristicWrite(gatt, characteristic, status);
activity.runOnUiThread(new Runnable() {
public void run()
{
}
});
}
@Override
public void onCharacteristicRead(BluetoothGatt gatt, final BluetoothGattCharacteristic characteristic, int status)
{
Log.d("onCharacteristicread",characteristic.getValue().toString());
Log.d("onCharacteristicread","called");
}
@Override
public void onCharacteristicChanged(BluetoothGatt gatt, final BluetoothGattCharacteristic characteristic) {
super.onCharacteristicChanged(gatt, characteristic);
byte[] charValue = characteristic.getValue();
final String str_result = bytesToHex(charValue);
Log.d("onCharacteristicfullres",str_result);
final Intent intent = new Intent("ble_data"); //FILTER is a string to identify this intent
intent.putExtra("val", "getdeviceinfo");
intent.putExtra("data", str_result);
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
activity.runOnUiThread(new Runnable() {
public void run()
{
// byte[] charValue = characteristic.getValue();
// String str_result = bytesToHex(charValue);
// Log.d("onCharacteristicfullres",str_result);
//Toast.makeText(activity, "On char changed "+str_result, Toast.LENGTH_SHORT).show();
}
});
}
@Override
public void onDescriptorWrite(final BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status)
{
activity.runOnUiThread(new Runnable() {
public void run()
{
Log.d("oncharadesc","abcd");
// prgd_progress.HideProgressDialog();
BluetoothGattService service = gatt.getService(UUID.fromString(SERVICE_ID));
for (BluetoothGattCharacteristic characteristics: service.getCharacteristics())
{
Log.d("getit",characteristics.getUuid().toString());
}
final BluetoothGattCharacteristic characteristic =
gatt.getService(UUID.fromString(SERVICE_ID)).getCharacteristics().get(0);
byte[] byt_arr;
byt_arr = hexStringToByteArray(value);
characteristic.setValue(byt_arr);
gatt.writeCharacteristic(characteristic);
}
});
}
};
BluetoothGatt bluetoothGatt = bluetoothDevice.connectGatt(activity, true, gattCallback);
}
