Local/ble gatt object references fix

BrickController2/BrickController2.Android/PlatformServices/BluetoothLE/BluetoothLEDevice.cs

@@ -114,6 +114,20 @@ internal void Disconnect()
             if (_bluetoothGatt != null)
             {
                 _bluetoothGatt.Disconnect();
+
+                // Android BLE best practice: Refresh the service cache before closing
+                // This prevents stale service information from being cached between reconnections
+                // The refresh() method is a hidden API, so we use reflection to call it
+                try
+                {
+                    var refreshMethod = _bluetoothGatt.Class?.GetMethod("refresh");
+                    refreshMethod?.Invoke(_bluetoothGatt);
+                }
+                catch
+                {
+                    // Silently ignore if refresh fails (not critical, but helpful)
+                }
+
                 _bluetoothGatt.Close();
                 _bluetoothGatt.Dispose();
                 _bluetoothGatt = null;

BrickController2/BrickController2.Tests/DeviceManagement/IO/OutputValuesGroupTests.cs

@@ -1,5 +1,6 @@
 using BrickController2.DeviceManagement.IO;
 using FluentAssertions;
+using System;
 using System.Collections.Generic;
 using Xunit;
 
@@ -42,6 +43,22 @@ public void Initialize_NoCommit_ChangeIsReportedFiveTimesOnly()
         lastValues.ToArray().Should().AllBeEquivalentTo(0);
     }
 
+    [Fact]
+    public void Clear_AnyChange_ReturnsFalseAndAllDefaultValues()
+    {
+        // Arrange
+        var group = new OutputValuesGroup<Half>(5);
+        group.SetOutput(3, Half.Pi);
+        // Act
+        group.Clear();
+
+        // Assert
+        var result = group.TryGetValues(out var values);
+        result.Should().BeFalse();
+        values.Length.Should().Be(5);
+        values.ToArray().Should().AllBeEquivalentTo(Half.Zero);
+    }
+
     [Theory]
     [InlineData(2)]
     [InlineData(7)]
@@ -115,7 +132,7 @@ public void Commit_ExistingChange_NoChangeIsReportedThen()
         changedValues.Should().BeEquivalentTo([new KeyValuePair<int, short>(0, 7)]);
 
         // Act
-        group.Commmit();
+        group.Commit();
 
         // Assert
         group.TryGetChanges(out var values).Should().BeFalse();

BrickController2/BrickController2/DeviceManagement/BluetoothDevice.cs

@@ -105,6 +105,8 @@ protected virtual void OnCharacteristicChanged(Guid characteristicGuid, byte[] d
         {
         }
 
+        protected abstract void OnDeviceDisconnecting();
+
         protected virtual Task<bool> AfterConnectSetupAsync(bool requestDeviceInformation, CancellationToken token)
         {
             return Task.FromResult(true);
@@ -116,9 +118,13 @@ private async Task DisconnectInternalAsync()
             {
                 await StopOutputTaskAsync();
                 DeviceState = DeviceState.Disconnecting;
+                // notify disconnection
+                OnDeviceDisconnecting();
+                // execute native device disconnection + cleanup
                 await _bleDevice.DisconnectAsync();
                 _bleDevice = null;
             }
+            _onDeviceDisconnected = null;
 
             DeviceState = DeviceState.Disconnected;
         }
@@ -129,8 +135,10 @@ private void OnDeviceDisconnected(IBluetoothLEDevice bluetoothLEDevice)
             {
                 using (await _asyncLock.LockAsync())
                 {
+                    var disconnectedCallback = _onDeviceDisconnected;
                     await DisconnectInternalAsync();
-                    _onDeviceDisconnected?.Invoke(this);
+                    // notify
+                    disconnectedCallback?.Invoke(this);
                 }
             });
         }

BrickController2/BrickController2/DeviceManagement/BuWizz2Device.cs

@@ -107,6 +107,14 @@ protected override async Task<bool> ValidateServicesAsync(IEnumerable<IGattServi
             return _characteristic is not null && _firmwareRevisionCharacteristic is not null && _modelNumberCharacteristic is not null;
         }
 
+        protected override void OnDeviceDisconnecting()
+        {
+            // Clear cached characteristic references to prevent using stale native Android objects on reconnection
+            _characteristic = null;
+            _modelNumberCharacteristic = null;
+            _firmwareRevisionCharacteristic = null;
+        }
+
         protected override void OnCharacteristicChanged(Guid characteristicGuid, byte[] data)
         {
             if (characteristicGuid != _characteristic!.Uuid || data.Length < 4 || data[0] != 0x00)

BrickController2/BrickController2/DeviceManagement/BuWizz3Device.cs

@@ -201,6 +201,13 @@ protected override Task<bool> ValidateServicesAsync(IEnumerable<IGattService>? s
 
             return Task.FromResult(_characteristic != null && _firmwareRevisionCharacteristic != null && _modelNumberCharacteristic != null);
         }
+        protected override void OnDeviceDisconnecting()
+        {
+            // Clear cached characteristic references to prevent using stale native Android objects on reconnection
+            _characteristic = null;
+            _modelNumberCharacteristic = null;
+            _firmwareRevisionCharacteristic = null;
+        }
 
         protected override void OnCharacteristicChanged(Guid characteristicGuid, byte[] data)
         {

BrickController2/BrickController2/DeviceManagement/BuwizzDevice.cs

@@ -81,6 +81,13 @@ protected override Task<bool> ValidateServicesAsync(IEnumerable<IGattService>? s
             return Task.FromResult(_characteristic is not null);
         }
 
+
+        protected override void OnDeviceDisconnecting()
+        {
+            // Clear cached characteristic reference to prevent using stale native Android objects on reconnection
+            _characteristic = null;
+        }
+
         protected override async Task ProcessOutputsAsync(CancellationToken token)
         {
             lock (_outputLock)

BrickController2/BrickController2/DeviceManagement/CircuitCubeDevice.cs

@@ -97,6 +97,13 @@ protected override void OnCharacteristicChanged(Guid characteristicGuid, byte[]
                 BatteryVoltage = bateryVoltage;
             }
         }
+        protected override void OnDeviceDisconnecting()
+        {
+            _writeCharacteristic = null;
+            _notifyCharacteristic = null;
+            _hardwareRevisionCharacteristic = null;
+            _firmwareRevisionCharacteristic = null;
+        }
 
         protected override async Task<bool> AfterConnectSetupAsync(bool requestDeviceInformation, CancellationToken token)
         {