Read RSSI (#796)

* Read RSSI of connected device

* Kotlin style issues

* Address review comments and add tests

---------

Co-authored-by: Tyler Norbury <[email protected]>
Co-authored-by: Sander Kersten <[email protected]>

Author: 3 people

example/lib/main.dart

@@ -29,6 +29,7 @@ void main() {
       return _ble.getDiscoveredServices(deviceId);
     },
     logMessage: _bleLogger.addToLog,
+    readRssi: _ble.readRssi,
   );
   runApp(
     MultiProvider(

example/lib/src/ble/ble_device_interactor.dart

@@ -6,11 +6,14 @@ class BleDeviceInteractor {
   BleDeviceInteractor({
     required Future<List<Service>> Function(String deviceId) bleDiscoverServices,
     required void Function(String message) logMessage,
+    required this.readRssi,
   })  : _bleDiscoverServices = bleDiscoverServices,
         _logMessage = logMessage;
 
   final Future<List<Service>> Function(String deviceId) _bleDiscoverServices;
 
+  final Future<int> Function(String deviceId) readRssi;
+
   final void Function(String message) _logMessage;
 
   Future<List<Service>> discoverServices(String deviceId) async {

example/lib/src/ui/device_detail/device_interaction_tab.dart

@@ -28,6 +28,7 @@ class DeviceInteractionTab extends StatelessWidget {
             connectionStatus: connectionStateUpdate.connectionState,
             deviceConnector: deviceConnector,
             discoverServices: () => serviceDiscoverer.discoverServices(device.id),
+            readRssi: () => serviceDiscoverer.readRssi(device.id),
           ),
         ),
       );
@@ -42,12 +43,14 @@ class DeviceInteractionViewModel extends $DeviceInteractionViewModel {
     required this.connectionStatus,
     required this.deviceConnector,
     required this.discoverServices,
+    required this.readRssi,
   });
 
   final String deviceId;
   final Connectable connectableStatus;
   final DeviceConnectionState connectionStatus;
   final BleDeviceConnector deviceConnector;
+  final Future<int> Function() readRssi;
 
   @CustomEquality(Ignore())
   final Future<List<Service>> Function() discoverServices;
@@ -78,6 +81,8 @@ class _DeviceInteractionTab extends StatefulWidget {
 class _DeviceInteractionTabState extends State<_DeviceInteractionTab> {
   late List<Service> discoveredServices;
 
+  int _rssi = 0;
+
   @override
   void initState() {
     discoveredServices = [];
@@ -91,6 +96,13 @@ class _DeviceInteractionTabState extends State<_DeviceInteractionTab> {
     });
   }
 
+  Future<void> readRssi() async {
+    final rssi = await widget.viewModel.readRssi();
+    setState(() {
+      _rssi = rssi;
+    });
+  }
+
   @override
   Widget build(BuildContext context) => CustomScrollView(
         slivers: [
@@ -118,10 +130,17 @@ class _DeviceInteractionTabState extends State<_DeviceInteractionTab> {
                     style: const TextStyle(fontWeight: FontWeight.bold),
                   ),
                 ),
+                Padding(
+                  padding: const EdgeInsetsDirectional.only(start: 16.0),
+                  child: Text(
+                    "Rssi: $_rssi dB",
+                    style: const TextStyle(fontWeight: FontWeight.bold),
+                  ),
+                ),
                 Padding(
                   padding: const EdgeInsets.only(top: 16.0),
-                  child: Row(
-                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+                  child: Wrap(
+                    alignment: WrapAlignment.spaceEvenly,
                     children: <Widget>[
                       ElevatedButton(
                         onPressed: !widget.viewModel.deviceConnected ? widget.viewModel.connect : null,
@@ -135,6 +154,12 @@ class _DeviceInteractionTabState extends State<_DeviceInteractionTab> {
                         onPressed: widget.viewModel.deviceConnected ? discoverServices : null,
                         child: const Text("Discover Services"),
                       ),
+                      ElevatedButton(
+                        onPressed: widget.viewModel.deviceConnected
+                            ? readRssi
+                            : null,
+                        child: const Text("Get RSSI"),
+                      ),
                     ],
                   ),
                 ),

example/lib/src/ui/device_detail/device_interaction_tab.g.dart

@@ -398,6 +398,12 @@ class FlutterReactiveBle {
   Future<void> clearGattCache(String deviceId) =>
       _blePlatform.clearGattCache(deviceId).then((info) => info.dematerialize());
 
+  /// Reads the RSSI of the of the peripheral with the given device ID. 
+  /// The peripheral must be connected, otherwise a [PlatformException] will be
+  /// thrown
+  Future<int> readRssi(String deviceId) async =>
+      _blePlatform.readRssi(deviceId);
+
   /// Subscribes to updates from the characteristic specified.
   ///
   /// This stream terminates automatically when the device is disconnected.

packages/flutter_reactive_ble/lib/src/reactive_ble.dart

@@ -143,6 +143,14 @@ class MockReactiveBlePlatform extends _i1.Mock
               _i2.Result<_i2.Unit,
                   _i2.GenericFailure<_i2.ClearGattCacheError>?>>);
   @override
+  _i4.Future<int> readRssi(String? deviceId) => (super.noSuchMethod(
+        Invocation.method(
+          #readRssi,
+          [deviceId],
+        ),
+        returnValue: _i4.Future<int>.value(0),
+      ) as _i4.Future<int>);
+  @override
   _i4.Stream<void> connectToDevice(
     String? id,
     Map<_i2.Uuid, List<_i2.Uuid>>? servicesWithCharacteristicsToDiscover,

packages/flutter_reactive_ble/test/connected_device_operation_test.mocks.dart

@@ -155,6 +155,14 @@ class MockReactiveBlePlatform extends _i1.Mock
               _i2.Result<_i2.Unit,
                   _i2.GenericFailure<_i2.ClearGattCacheError>?>>);
   @override
+  _i4.Future<int> readRssi(String? deviceId) => (super.noSuchMethod(
+        Invocation.method(
+          #readRssi,
+          [deviceId],
+        ),
+        returnValue: _i4.Future<int>.value(0),
+      ) as _i4.Future<int>);
+  @override
   _i4.Stream<void> connectToDevice(
     String? id,
     Map<_i2.Uuid, List<_i2.Uuid>>? servicesWithCharacteristicsToDiscover,

packages/flutter_reactive_ble/test/device_connector_test.mocks.dart

@@ -143,6 +143,14 @@ class MockReactiveBlePlatform extends _i1.Mock
               _i2.Result<_i2.Unit,
                   _i2.GenericFailure<_i2.ClearGattCacheError>?>>);
   @override
+  _i4.Future<int> readRssi(String? deviceId) => (super.noSuchMethod(
+        Invocation.method(
+          #readRssi,
+          [deviceId],
+        ),
+        returnValue: _i4.Future<int>.value(0),
+      ) as _i4.Future<int>);
+  @override
   _i4.Stream<void> connectToDevice(
     String? id,
     Map<_i2.Uuid, List<_i2.Uuid>>? servicesWithCharacteristicsToDiscover,

packages/flutter_reactive_ble/test/device_scanner_test.mocks.dart

@@ -486,6 +486,14 @@ void main() {
       });
     });
 
+    test('Read RSSI', () async {
+      const deviceId = '123';
+
+      when(_blePlatform.readRssi(deviceId)).thenAnswer((_) async => -42);
+
+      expect(await _sut.readRssi(deviceId), -42);
+    });
+
     group('ConnecteddeviceStream stream', () {
       const update = ConnectionStateUpdate(
         deviceId: '123',

packages/flutter_reactive_ble/test/reactive_ble_test.dart

@@ -146,6 +146,14 @@ class MockReactiveBlePlatform extends _i1.Mock
               _i2.Result<_i2.Unit,
                   _i2.GenericFailure<_i2.ClearGattCacheError>?>>);
   @override
+  _i4.Future<int> readRssi(String? deviceId) => (super.noSuchMethod(
+        Invocation.method(
+          #readRssi,
+          [deviceId],
+        ),
+        returnValue: _i4.Future<int>.value(0),
+      ) as _i4.Future<int>);
+  @override
   _i4.Stream<void> connectToDevice(
     String? id,
     Map<_i2.Uuid, List<_i2.Uuid>>? servicesWithCharacteristicsToDiscover,