BLE select cancel

lib/connector/meshcore_connector.dart

@@ -686,12 +686,19 @@ class MeshCoreConnector extends ChangeNotifier {
   }) async {
     if (_state == MeshCoreConnectionState.scanning) return;
 
+    try {
       _scanResults.clear();
       _setState(MeshCoreConnectionState.scanning);
 
       // Ensure any previous scan is fully stopped
+      try {
         await FlutterBluePlus.stopScan();
+      } catch (_) {}
+      
+      try {
         await _scanSubscription?.cancel();
+      } catch (_) {}
+      _scanSubscription = null;
 
       // On iOS/macOS, wait for Bluetooth to be powered on before scanning
       if (PlatformInfo.isIOS || PlatformInfo.isMacOS) {
@@ -714,7 +721,8 @@ class MeshCoreConnector extends ChangeNotifier {
         await Future.delayed(const Duration(milliseconds: 300));
       }
 
-    _scanSubscription = FlutterBluePlus.scanResults.listen((results) {
+      _scanSubscription = FlutterBluePlus.scanResults.listen(
+        (results) {
           _scanResults.clear();
           for (var result in results) {
             if (result.device.platformName.startsWith("MeshCore-") ||
@@ -724,7 +732,12 @@ class MeshCoreConnector extends ChangeNotifier {
             }
           }
           notifyListeners();
-    });
+        },
+        onError: (Object e) {
+          debugPrint("scanResults stream error: $e");
+          stopScan();
+        },
+      );
 
       await FlutterBluePlus.startScan(
         withServices: [Guid(MeshCoreUuids.service)],
@@ -733,17 +746,36 @@ class MeshCoreConnector extends ChangeNotifier {
       );
 
       await Future.delayed(timeout);
+    } catch (e) {
+      debugPrint("Scan error: $e");
+      // On web, suppress common cancellation and chooser errors
+      if (kIsWeb) return;
+      
+      if (!PlatformInfo.isWeb) {
+        rethrow;
+      }
+    } finally {
       await stopScan();
     }
+  }
 
   Future<void> stopScan() async {
-    await FlutterBluePlus.stopScan();
-    await _scanSubscription?.cancel();
-    _scanSubscription = null;
-
     if (_state == MeshCoreConnectionState.scanning) {
       _setState(MeshCoreConnectionState.disconnected);
     }
+
+    try {
+      await FlutterBluePlus.stopScan();
+    } catch (e) {
+      debugPrint("stopScan error: $e");
+    }
+
+    try {
+      if (_scanSubscription != null) {
+        await _scanSubscription!.cancel();
+      }
+    } catch (_) {}
+    _scanSubscription = null;
   }
 
   Future<void> connect(BluetoothDevice device, {String? displayName}) async {
@@ -770,11 +802,17 @@ class MeshCoreConnector extends ChangeNotifier {
     notifyListeners();
 
     try {
-      _connectionSubscription = device.connectionState.listen((state) {
+      _connectionSubscription = device.connectionState.listen(
+        (state) {
           if (state == BluetoothConnectionState.disconnected && isConnected) {
             _handleDisconnection();
           }
-      });
+        },
+        onError: (Object e) {
+          debugPrint("connectionState stream error: $e");
+          if (isConnected) _handleDisconnection();
+        },
+      );
 
       await device.connect(
         timeout: const Duration(seconds: 15),
@@ -833,6 +871,9 @@ class MeshCoreConnector extends ChangeNotifier {
       }
       _notifySubscription = _txCharacteristic!.onValueReceived.listen(
         _handleFrame,
+        onError: (Object e) {
+          debugPrint("onValueReceived stream error: $e");
+        },
       );
 
       _setState(MeshCoreConnectionState.connected);

lib/screens/scanner_screen.dart

@@ -45,7 +45,8 @@ class _ScannerScreenState extends State<ScannerScreen> {
 
     connector.addListener(_connectionListener);
 
-    _bluetoothStateSubscription = FlutterBluePlus.adapterState.listen((state) {
+    _bluetoothStateSubscription = FlutterBluePlus.adapterState.listen(
+      (state) {
         if (mounted) {
           setState(() {
             _bluetoothState = state;
@@ -55,7 +56,11 @@ class _ScannerScreenState extends State<ScannerScreen> {
             unawaited(connector.stopScan());
           }
         }
-    });
+      },
+      onError: (Object e) {
+        debugPrint("Scanner adapterState stream error: $e");
+      },
+    );
   }
 
   @override
@@ -107,7 +112,9 @@ class _ScannerScreenState extends State<ScannerScreen> {
                     if (isScanning) {
                       connector.stopScan();
                     } else {
-                      connector.startScan();
+                      unawaited(connector.startScan().catchError((e) {
+                        debugPrint("Scanner screen startScan error: $e");
+                      }));
                     }
                   },
             icon: isScanning