All Questions
Tagged with android-ble bluetooth
57
questions
13
votes
4
answers
24k
views
Android BLE Gatt connection change statuses
I have an android app to connect to a BLE device and write to it. I can successfully connect, read and write to it. As a part of testing, we are trying different disconnection scenarios.
Sometimes, if ...
- 5,862
7
votes
2
answers
4k
views
Reacting to BLE directed advertising (ADV_DIRECT_IND) in Android
How to react to directed advertising (ADV_DIRECT_IND == 0001) in Android?
There is a BLE-gadget which sends directed advertising to an Android phone (using hardcoded MAC address of the phone for now) ...
- 22.4k
5
votes
1
answer
9k
views
android - stopLeScan() & startLeScan() deprecated in API Level 22 - How do I go about replacing this with stopScan() and startScan()?
I see that stopLeScan() & startLeScan() are deprecated in Android 5.1.1. I am having issues replacing my stopLeScan() & startLeScan() methods. Here is my following code:
@Override
protected ...
- 1,917
5
votes
2
answers
6k
views
How do I make sure app is disconnecting from a Bluetooth LE device?
I have two devices that I'm connecting to. When I leave the app I'm disconnecting from the devices. Both go through the same process but sometimes one of the devices maintains a connection until I ...
- 676
4
votes
3
answers
8k
views
Open source implementations of BLE stack
Are there any open source implementations of BLE stack other than BlueZ and Bluedroid?
- 41
4
votes
2
answers
5k
views
Sending Large File via BLE API on android
I have created BLE sender class for the sending large ByteArray via Bluetooth LE
The logic of the send process following:
Write descriptor to enable notification on characteristics that sends data ...
- 81
4
votes
1
answer
801
views
Android - BLE bonding programmatically doesn't work on all CoolPad Note 3
I am using below broadcast receiver to catch bond request and bond it without user popup request.
private static BroadcastReceiver pairingBroadcastReceiver = new BroadcastReceiver() {
@...
- 5,862
4
votes
0
answers
3k
views
How to create Bluetooth L2CAP connection between two devices?
Android 10 released support for BLE CoC connection so I wanted to try this out by making two simple android 10 apps, which would connect to each other with l2Cap and exchange "Hello World".
I wrote ...
4
votes
0
answers
891
views
Why does a text box appear behind the Bluetooth permission dialog for my Android app?
I am writing an app that requires Bluetooth to be enabled to use and there is a strange "title like" set of text that appears behind the alert dialog that asks to enable Bluetooth. The text says "...
- 1,113
3
votes
3
answers
3k
views
Android: adding ScanCallback gives me "Unfortunately, App has stopped." can't find MainActivity
I am very new to android dev. I've watched a few youtube video's and read some documentation. Today is like day 5, so be patient with me. I am trying to build a BluetoothLE app. I stole some code from ...
- 9,206
3
votes
1
answer
2k
views
Android BluetoothGatt not receving Characteristic Notifications BluetoothGatt#writeDescriptor(desc) return false
I am working on an application which needs to communicate with a Bluetooth LE device.
This is the code I use to set the CharacteristicNotification
public boolean setCharacteristicNotification(
...
- 155
3
votes
1
answer
8k
views
onCharacteristicWrite() is being called, but it doesn't always write
I have a custom piece of hardware with a bluetooth low energy chip. I have set it up with an array with 500 u32s such that array[n] == n. I'm working on an android app that can connect to the device, ...
- 126
3
votes
1
answer
3k
views
How to detect whenever my android device gets connected/disconnected from paired bluetooth device
I would like to receive an event for detecting whenever bluetooth gets paired or unpaired in my device.
In the beginning i found http://developer.android.com/reference/android/bluetooth/...
- 4,182
3
votes
1
answer
1k
views
Turning off Bluetooth Adapter not calling onConnectionStateChange Android 8.1.0
Turning off the bluetooth in Android system settings gives us the BluetoothGattCallback.onConnectionStateChange() call in Android < 27 (Oreo). However when I try it on my Pixel or Nexus 5X (Android ...
- 1,188
3
votes
1
answer
2k
views
WiFi connection issues when BLE scan always on
I'm currently scanning BLE devices continuosly and undefenetily, but I noticed that my Samsung J1 loose wifi connections, and any atempt to reconect gives "Authentication Error":"Password incorrect". ...
- 18.2k
3
votes
0
answers
571
views
BLE - How to get response after writing command?
I have a BLE device with a "particular protocol".
I need to send a command to retrieve heart rate measurements (using notifications).
My question is: how can I get response after write the "send ...
- 1,435
2
votes
1
answer
1k
views
How to make Android connect after the Bluetooth Adapter has been disabled & reenabled?
I have written an app that connects to a BLE device. The app works OK on most devices; but some devices (most noticeably Huawei P8 Lite and Nexus 6P) refuse to connect after the Bluetooth adapter has ...
- 175
2
votes
1
answer
2k
views
BluetoothServiceJni: An exception was thrown by callback 'btgattc_notify_cb'
I am using Android ble to develop an application. The app will connect with the external device using ble. The external device has a sensor that records data and as soon as the android device comes in ...
- 434
2
votes
1
answer
791
views
Get the supported Bluetooth Version in Android phones?(5 or 4.x)
Is there a way to know the Android Bluetooth Ver?( 5 or 4.x - 4.1 or 4.2?)
Currently as per
https://developer.android.com/about/versions/oreo/android-8.0-changes
Feature like Advertisement packet ...
- 7,968
2
votes
1
answer
6k
views
Scanning for BLE devices on Android 8+ in the background
I'm using the following method from BLE scanner API on Android 8+
to scan for BLE Beacons
startScan(List<ScanFilter> filters, ScanSettings settings,
PendingIntent callbackIntent)
The problem ...
- 1,861
2
votes
2
answers
2k
views
How to connect with BLE device for first time (Android)
I was going through BluetoothGatt.java and found the method boolean connect(Boolean autoConnect, BluetoothGattCallback callback,
Handler handler)
The documentation just above this method ...
- 434
2
votes
0
answers
2k
views
Android BLE Gatt Connection Issue (Connection Timeout Status:8)
I'm developing an Android app that discovers and connects to a GATT service that is being advertised by my rPi 3B+. The iOS app that I've finished developing works without any issue. However, almost ...
- 21
2
votes
0
answers
914
views
Android BluetoothGatt.getServices(xyz) in onServicesDiscovered returns null for Service xyz listed in onScanResult ScanRecord.getServiceUuids()
I've been doing BLE on Android since 2013/API18/4.3.
I know what I am doing, but I can't figure out this simple problem.
I am successfully scanning BLE devices and in ScanCallback.onScanResult(...) I ...
- 3,105
2
votes
1
answer
1k
views
Android BluetoothDevice connectGatt not working on HTC M8 with Android 6.0
I have a BLE app that has hundreds of happy users on a variety of devices. Most of my testing has been done on Nexus devices, but a user reported an issue with HTC M8 so I just bought one. Sure enough,...
- 930
1
vote
1
answer
1k
views
Trouble Connecting Android App to Raspberry Pi 3 over BLE
I am using the Raspberry Pi 3 model B as a bluetooth peripheral.
The Pi is running a GATT server and advertising it as well.
I can connect to it from the LightBlue iOS app and can read and write ...
- 61
1
vote
1
answer
1k
views
Android - What API can I use to see if a device supports BLE central mode?
https://developer.android.com/guide/topics/connectivity/bluetooth-le#roles
Central vs. peripheral. This applies to the BLE connection itself. The
device in the central role scans, looking for ...
- 1,208
1
vote
2
answers
1k
views
Can I have an encrypted BLE connection without bonding? / Pairing BLE devices without bonding
So far I am able to do things two different ways.
I can advertise a service on the Pi, connect from an Android app, and read/write characteristics. From my understanding, this communication is not ...
- 133
1
vote
1
answer
3k
views
Android BLE: Is it possible to add Service Data and Manufacturer Data at the same time when advertising an iBeacon packet?
I'm currently doing an experiment in order to trigger a beacon detection device. Here is the sample of a detected beacon that can be used to trigger that device.
In my experiment, I'm trying to ...
- 63
1
vote
1
answer
1k
views
Android BLE Peripheral Mode: custom characteristics not detected
I am trying to implement a BluetoothGattServer on a Sony SmartWatch 3.
I can sucessfully open a Gatt server as well as advertise.
Using the BLE Scanner application, I have inconsistent results while ...
- 3,433
1
vote
2
answers
4k
views
BluetoothDevice always returns null on getName()
I'm facing this issue consistently in Android 4.4, 5 and 6.
I'm performing a BLE Bluetooth devices scan and after it I can access their address (getAddress()), and other data. But if I call device....
- 829
1
vote
0
answers
89
views
Is there any solutions available to send data from BluetoothGattServer to connected devices simultaneously?
Here is my server code:
private BluetoothGattServer mGattServer;
mBluetoothLeAdvertiser = mBluetoothAdapter.getBluetoothLeAdvertiser();
GattServerCallback gattServerCallback = new GattServerCallback(...
- 11
1
vote
1
answer
178
views
ScanCall back not Coming in Android Oreo
I am not able to get my ble scanner working.There is no scanCalll Back is occuring.
Below is my code:
MainActivity:
public class MainActivity extends AppCompatActivity {
@Override
...
- 7,968
1
vote
0
answers
684
views
onCharacteristicChanged getting called multiple times without change in Characteristic values
I'm developing an android bluetooth low energy app where I'm getting data from a peripheral device in a single characteristic. I have enabled notifications on this characteristic and process ...
- 168
1
vote
0
answers
59
views
gatt.disconnect() is initiated host but not by the app
I've been breaking my head with this issue....
i send a gatt.write command to my remote device, sometimes getting response and sometimes not because the gatt disconnects at all times from my app! (...
- 185
1
vote
0
answers
187
views
New Lollipop BLE API does not detect all advertising packets
I have seen a few posts with the same question but I have no been able to get a solution for my problem.
I see that the callback function (onScanResult) for the new BLE API detects advertising ...
- 181
1
vote
1
answer
1k
views
How to extract latitude and longitude from location_and_speed characteristic?
In an Android app in central role - how do you please get a hold of the latitude and longitude stored in the org.bluetooth.characteristic.location_and_speed characteristic in the org.bluetooth.service....
- 22.4k
0
votes
1
answer
700
views
BLE packet drops when Bluetooth and BLE are simultaneously in use
I am using BLE v4.1 for my application where I am able to transfer 200 packets of length 20 bytes each from peripheral to central side.
I want to transfer data via BLE and play some music while the ...
- 83
0
votes
1
answer
573
views
Handling Notifications on Android with Multiple BLE Peripheral Connections
So, I am new to Android development and I am trying to connect my device to multiple BLE devices (T-Wristband) to receive frequent notifications (IMU sensor data less than 20 bytes at 50Hz).
When ...
0
votes
1
answer
373
views
Android BluetoothLe keeping Gatt client-server connection alive
I am developing an android BLE application and I have successfully created the app which connects with the BLE peripheral. Right now Gatt server gets disconnected and reconnected again on interval of ...
- 611
0
votes
1
answer
910
views
Android BLE callback OnWriteCallback stops after few seconds
I am trying to write next packet synchronously based on the OnCharacteristicWrite call back condition to achieve a maximum throughput. But for some reason it stops triggering OnCharacteristicWrite ...
0
votes
1
answer
597
views
How to check if a bluetooth response is received within a particular time limit?
I'm developing an app bluetooth to communicate with a device.
I have to send to that device a certain packet and that device respond to me in notify mode after a certain time.
All works well, but I ...
- 1,064
0
votes
0
answers
31
views
Uncaught exception thrown by finalizer for Bluetooth Reconnection in Android - java.io.IOException: socket not created
Thanks in advance for helping. I am trying to work with a Serial Bluetooth connection where I am connecting and communicating to the IOT device serially over Bluetooth. So the device has On/Off switch ...
0
votes
1
answer
241
views
How to scan BLE devices that use Extended Advertisement and Coded PHY with Android?
I try do create an Android app that scan Bluetooth Low Energy devices that advertise using Extended Advertisement and use Coded PHY for advertisement.
I have a nrf52840 peripheral that I have setup to ...
- 125k
0
votes
1
answer
298
views
onPhyUpdate is triggered with status 6 = GATT_REQUEST_NOT_SUPPORTED
I'm developing an Android app which communicates via BLE with an external module, and I am trying to set the BLE connection PHY.
I've tried calling the method gatt.setPreferredPhy(txPhy, rxPhy, ...
- 115
0
votes
0
answers
224
views
Can't read the value that comes with the GATT Service characteristic; Not sure if I setup the GATT server correctly
The BLE is advertising just fine. I can establish a connection with it but I can't read the characteristic value I set here on the initialization of GATT server.
This is the GATT Server setup
@...
- 31
0
votes
0
answers
543
views
Android periodic ble scan
I have a BLE thermometer that advertises current temperature exactly every 5 seconds.
I want to write an app (service) for my Android 9 phone (Xiaomi), that will perform periodic BLE scan to read the ...
- 1,242
0
votes
1
answer
200
views
Android BLE devices not detecting each other
I am trying to use Google's Sample BLE library to send data between two LG Phoenix 4 phones, both running Android 7.1 and both BLE-compatible. I have successfully gotten the app onto both phones, but ...
- 1
0
votes
1
answer
2k
views
BLE - Bluetooth GATT service can't close connection
I have implemented BLE and it works. The flow is: DrawerActivity starts, it sets a fragmentA, which has BLE implementation, because I want active BLE only in fragmentA. So if you switch to fragmentB ...
- 1,579
0
votes
0
answers
175
views
Android BLE Design Pattern viability
I have looked on numerous topics on android BLE stack in various website. From what i gathered, the bluetooth stack in android is unreliable and not suitable for any fast and concurrent connection.
...
- 2,733
0
votes
1
answer
1k
views
Android O : Ble Scanner not scanning - Not getting any scan call back event
I am using google pixel with Android O . I am seeing that in my application after a while there is no scan call back coming .
Below is the btif log I have captured
11-02 19:18:20.561 19922-19985/? E/...
- 7,968