Flutter_blue: Unable to get both bluetooth device list (paired and near by) in Android version 9

[rahul-jain-7893]

By using this code. Unable to get bluetooth device list.

flutterBlue.startScan(timeout: Duration(seconds: 4));

// Listen to scan results
var subscription = flutterBlue.scanResults.listen((results) {
// do something with scan results
for (ScanResult r in results) {
print('${r.device.name} found! rssi: ${r.rssi}');
}
});

// Stop scanning
flutterBlue.stopScan();

[AuspeXeu]

Same for me under Android 9, it works sometimes though...

[Darren-FanDemand]

I tried on both android 9 and 6. I don't get the list. Please assist.

[Hritik14]

Could be related to https://github.com/pauldemarco/flutter_blue/issues/581

[AuspeXeu]

At least not for me, I have that in my manifest :)

[Darren-FanDemand]

I added the permission but that didn't seem to make a difference. I'm testing from an android phone. I have two additional devices with bluetooth switched on (another android phone and an iPod). They all see each other via the OS. When I run the app, the plugin does not see those devices. Funny enough though, today it consistently detected a random LG device somewhere in my building but not the devices I have right here in my apartment.

[Hritik14]

That is weird. Can you try installing the example file that comes along?

[Hritik14]

I can confirm this issue.
The example app is unable to identify some of the devices nearby and is able to detect others.
Device detected: 08:25:25:7a:XX:XX
Device undetected: 38:e6:0a:e3:XX:XX

[AuspeXeu]

Just a hunch maybe it's related to the allowDuplicates option? Also, I just realized the code from the initial issue stops scanning immediately again...

[philos3]

By using this code. Unable to get bluetooth device list.

flutterBlue.startScan(timeout: Duration(seconds: 4));
// Listen to scan results
var subscription = flutterBlue.scanResults.listen((results) {
// do something with scan results
for (ScanResult r in results) {
print('${r.device.name} found! rssi: ${r.rssi}');
}
});
// Stop scanning
flutterBlue.stopScan();

add uses-permission in androidMainifest.xml

<uses-permission android:name="android.permission.BLUETOOTH" 
/>
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" 
/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"
 />
 <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION"
/>

    <uses-feature
        android:name="android.hardware.bluetooth_le"
        android:required="true" />

[Darren-FanDemand]

By using this code. Unable to get bluetooth device list.

flutterBlue.startScan(timeout: Duration(seconds: 4));
// Listen to scan results
var subscription = flutterBlue.scanResults.listen((results) {
// do something with scan results
for (ScanResult r in results) {
print('${r.device.name} found! rssi: ${r.rssi}');
}
});
// Stop scanning
flutterBlue.stopScan();

add uses-permission in androidMainifest.xml

<uses-permission android:name="android.permission.BLUETOOTH" 
/>
    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" 
/>
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"
 />
 <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION"
/>

    <uses-feature
        android:name="android.hardware.bluetooth_le"
        android:required="true" />

Thanks but this doesn't solve the current problem. The plugin still doesn't detect all the devices around.

[Wassim24]

Have you tried enabling location ? I had the same exact problem once, this solved it.
Also, flutter blue supports only BLE (Beacons) if i understand correctly, it won't detect others.

[AuspeXeu]

Just some clues I found. I have the same BT device one time paired to my Pixel XL, one time not paired. When paired, I don't find it. When not paired, I find it. Did the same experiment with a Samsung S9. For this one it's the opposite. When paired, I find it. When not paired, I don't find it.

Can anyone make sense of this?

[zwells]

Maybe add the following in AndroidManifest.xml:
uses-permission android:name="android.permission.FOREGROUND_SERVICE"