[Help]: about 'another scan already in progress'

[ringonotts]

FlutterBluePlus Version

1.14.11

Flutter Version

3.10.1

What OS?

Android

OS Version

13

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I am migrating my application from flutter_blue and have the following code for scanning:

FlutterBluePlus
            .scan(timeout: const Duration(seconds: 5), androidUsesFineLocation: false)
                .listen((scanResult) {
      // do something with scan result
      _scanListenHandler(scanResult, id);
    }).onDone(() async {
      _isScanning = false;
      await FlutterBluePlus.stopScan();
      setState(() {});
      if (!_isAdding) {
        myUtils.toast("No Sensors detected");
      }
    });

I perform the scan and am getting an exception 'another scan already in progress' from flutter_blue_plus.dart line 148.

When i set a breakpoint on line 146 I can see I hit this scan() method twice. The first time I hit the method _isScanning.value == false, and there is a call stack to where i called the scan function. The second time I hit the breakpoint (note _scanListenHandler() has not been called) _isScanning.value == true and there is no call stack - just a "asyncronous gap". Obviously it's this second call to scan() causing the exception.

Why is the scan() method called twice ? Am i calling it correctly ? Note I need to know when the scan is complete so i can stop the circular progress indicator in my app (hence not using startScan()).

Thanks in advance, Ringo

Logs

I/orthings.batmon(22261): Compiler allocated 4413KB to compile void android.view.ViewRootImpl.performTraversals()
D/CompatibilityChangeReporter(22261): Compat change id reported: 183155436; UID 10263; state: ENABLED
I/FirebaseApp(22261): Device unlocked: initializing all Firebase APIs for app [DEFAULT]
D/CompatibilityChangeReporter(22261): Compat change id reported: 78294732; UID 10263; state: ENABLED
I/flutter (22261): PermissionStatus.granted
D/[FBP-Android](22261): [FBP-Android] onMethodCall: setLogLevel
D/[FBP-Android](22261): [FBP-Android] initializing BluetoothAdapter
D/[FBP-Android](22261): [FBP-Android] onMethodCall: getAdapterState
D/[FBP-Android](22261): [FBP-Android] onMethodCall: setLogLevel
D/[FBP-Android](22261): [FBP-Android] onMethodCall: startScan
D/BluetoothAdapter(22261): isLeEnabled(): ON
D/BluetoothLeScanner(22261): onScannerRegistered() - status=0 scannerId=4 mScannerId=0

[chipweinberger]

I don't think I can answer this for you with the code given.

But you can check FlutterBluePlus.isScanningNow to make sure you do not call it twice.

[ringonotts]

Thanks Chip for getting back to me. Actually you were a great help!