Scanning BLE device not working

Question

I am trying to scan BLE devices with

mBluetoothAdapter.startLeScan(this);

(I know its obsolete for newer versions but just to see it works with my phone [4.4], I am using it). So it starts scanning and then moves on without giving errors but no device is detected. OnLEScan event is also fired but the device parameter in it is null. My LE device is right there and connected.

On googling, I found this happens if the BluetoothAdapter doesnot have a UUID. How do I set UUID? When is OnLeScan called/fired? Is there any other solution?

My callback code goes here

//BluetoothAdapte.LEScanCallBack on MainActivity
@Override
public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord){
    Log.i(TAG, "New LE Device: " + device.getName() + "@" + rssi);
    if(Device_Name.equals(device.getName())){
            mDevices.put(device.hashCode(), device);
            invalidateOptionsMenu();
        }
}

score 1 · Answer 1 · answered Jul 05 '16 at 07:45

Use this code as it will provide you insight of all the data available in your BLE device (will display the data in logs).
UUIDs are basically provided by the manufacturer of the device and you can't set it on your own.
For Instance : I was using BLE Beacons and its manufacturer provided me the API which helped me to fetch its UUID.

Sometimes, a special ID is available on the device itself(factory id in my case) which can help you to retrieve your UUID and that too from the manufacturer's website or API.

BluetoothAdapter bluetoothAdapter;
BluetoothLeScanner bluetoothLeScanner;



bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
bluetoothLeScanner = bluetoothAdapter.getBluetoothLeScanner();



    bluetoothLeScanner.startScan(new ScanCallback() {
        @Override
        public void onScanResult(int callbackType, ScanResult result) {
            super.onScanResult(callbackType, result);

            String s = "\nRssi : "+result.getRssi()+"" +
                    "\nName (Get Device) : "+result.getDevice().getName()+"" +
                    "\nBytes"+result.getScanRecord().getBytes()+"" +
                    "\nGet Device : " + result.getDevice()+"" +
                    "\nAddress : "+result.getDevice().getAddress()+"" +
                    "\nService UUIds : "+result.getScanRecord().getServiceUuids().get(0)+"" +       //Unique
                    "\nName (Scan Record) : "+result.getScanRecord().getDeviceName()+"" +
                    "\nUuids device : "+result.getDevice().getUuids()+"" +
                    "\nDescribe contents : "+result.describeContents();

            //This will show you all the data in logs.
            Log.e("All Data",s);



        }

        @Override
        public void onBatchScanResults(List<ScanResult> results) {
            super.onBatchScanResults(results);
        }

        @Override
        public void onScanFailed(int errorCode) {
            super.onScanFailed(errorCode);
        }
    });

}

Thanks a bunch! seems like the right answer only that I am getting error: method lookup failed for selector "getBluetoothLeScanner" with signature "()Landroid/bluetooth/le/BluetoothLeScanner;" when i do this -> mBluetoothLeScanner = mBluetoothAdapter.getBluetoothLeScanner(); — Samra, Jul 07 '16 at 01:13
You might be getting this error because **BluetoothLeScanner** was added in API 21 (Android 5.0). So, try to set `minSdkVersion 21`. — Nishant Thapliyal, Jul 07 '16 at 04:42
No errors now but same issue, now also no device is detected. In my Android Manifest file i have permissions for bluetooth, bluetooth_admin, Coarse_location, Fine_Location. My GPS and bluetooth are both on in my device — Samra, Jul 08 '16 at 03:39

score 0 · Accepted Answer · answered Feb 28 '17 at 00:37

0

Anroid 4.4 is not compatible, i used android 5.1 device and it worked like a charm!

answered Feb 28 '17 at 00:37

Samra

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Scanning BLE device not working

2 Answers2