1.6.0

open_wearable/android/app/src/main/AndroidManifest.xml

@@ -14,6 +14,7 @@
         <!-- Don't delete the meta-data below.
              This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
         <meta-data android:name="flutterEmbedding" android:value="2"/>
+        <service android:name=".AudioRecordingService" android:exported="false" android:foregroundServiceType="microphone"/>
     </application>
     <!-- Required to query activities that can process text, see:
          https://developer.android.com/training/package-visibility and
@@ -41,6 +42,7 @@
     <uses-permission android:name="android.permission.INTERNET"/>
 
     <uses-permission android:name="android.permission.RECORD_AUDIO" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MICROPHONE" />
 
     <!-- Provide required visibility configuration for API level 30 and above -->
     <queries>

open_wearable/android/app/src/main/kotlin/edu/kit/teco/openwearables/AudioRecordingService.kt

@@ -0,0 +1,64 @@
+package edu.kit.teco.openWearable
+
+import android.app.Notification
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.app.Service
+import android.content.Intent
+import android.content.pm.ServiceInfo
+import android.os.Build
+import android.os.Bundle
+import android.os.IBinder
+import android.os.ResultReceiver
+
+/** Keeps an explicitly started microphone recording audible while the app is backgrounded. */
+class AudioRecordingService : Service() {
+  override fun onBind(intent: Intent?): IBinder? = null
+
+  override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+    @Suppress("DEPRECATION")
+    val receiver = intent?.getParcelableExtra<ResultReceiver>("result")
+    try {
+      val channelId = "audio_recording"
+      val manager = getSystemService(NotificationManager::class.java)
+      val builder = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+        manager.createNotificationChannel(
+          NotificationChannel(channelId, "Audio recording", NotificationManager.IMPORTANCE_LOW),
+        )
+        Notification.Builder(this, channelId)
+      } else {
+        @Suppress("DEPRECATION")
+        Notification.Builder(this)
+      }
+      val openApp = PendingIntent.getActivity(
+        this, 0, Intent(this, MainActivity::class.java),
+        PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE,
+      )
+      val notification = builder
+        .setSmallIcon(android.R.drawable.ic_btn_speak_now)
+        .setContentTitle("OpenWearables is recording audio")
+        .setContentText("Open the app to stop recording.")
+        .setContentIntent(openApp)
+        .setOngoing(true)
+        .setOnlyAlertOnce(true)
+        .setCategory(Notification.CATEGORY_SERVICE)
+        .build()
+      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+        startForeground(104, notification, ServiceInfo.FOREGROUND_SERVICE_TYPE_MICROPHONE)
+      } else {
+        startForeground(104, notification)
+      }
+      receiver?.send(0, null)
+    } catch (error: Exception) {
+      receiver?.send(1, Bundle().apply { putString("error", error.message) })
+      stopSelf()
+    }
+    return START_NOT_STICKY
+  }
+
+  override fun onDestroy() {
+    stopForeground(STOP_FOREGROUND_REMOVE)
+    super.onDestroy()
+  }
+}

open_wearable/android/app/src/main/kotlin/edu/kit/teco/openwearables/MainActivity.kt

@@ -1,6 +1,11 @@
 package edu.kit.teco.openWearable
 
 import android.content.Intent
+import android.os.Build
+import android.os.Bundle
+import android.os.Handler
+import android.os.Looper
+import android.os.ResultReceiver
 import android.provider.Settings
 import io.flutter.embedding.android.FlutterActivity
 import io.flutter.embedding.engine.FlutterEngine
@@ -14,6 +19,35 @@ class MainActivity : FlutterActivity() {
   override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
     super.configureFlutterEngine(flutterEngine)
 
+    MethodChannel(
+      flutterEngine.dartExecutor.binaryMessenger,
+      "edu.kit.teco.openWearable/audio_recording",
+    ).setMethodCallHandler { call, result ->
+      val intent = Intent(this, AudioRecordingService::class.java)
+      when (call.method) {
+        "start" -> {
+          val receiver = object : ResultReceiver(Handler(Looper.getMainLooper())) {
+            override fun onReceiveResult(code: Int, data: Bundle?) {
+              if (code == 0) result.success(null)
+              else result.error("audio_recording_service", data?.getString("error"), null)
+            }
+          }
+          intent.putExtra("result", receiver)
+          try {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) startForegroundService(intent)
+            else startService(intent)
+          } catch (error: Exception) {
+            result.error("audio_recording_service", error.message, null)
+          }
+        }
+        "stop" -> {
+          stopService(intent)
+          result.success(null)
+        }
+        else -> result.notImplemented()
+      }
+    }
+
     MethodChannel(
       flutterEngine.dartExecutor.binaryMessenger,
       SYSTEM_SETTINGS_CHANNEL,
@@ -33,4 +67,9 @@ class MainActivity : FlutterActivity() {
       }
     }
   }
+
+  override fun onDestroy() {
+    stopService(Intent(this, AudioRecordingService::class.java))
+    super.onDestroy()
+  }
 }

open_wearable/lib/apps/heart_tracker/widgets/heart_tracker_page.dart

@@ -7,6 +7,7 @@ import 'package:open_wearable/apps/heart_tracker/model/ppg_filter.dart';
 import 'package:open_wearable/apps/heart_tracker/widgets/rowling_chart.dart';
 import 'package:open_wearable/models/wearable_display_group.dart';
 import 'package:open_wearable/view_models/sensor_configuration_provider.dart';
+import 'package:open_wearable/view_models/wearables_provider.dart';
 import 'package:open_wearable/widgets/devices/devices_page.dart';
 import 'package:provider/provider.dart';
 
@@ -29,6 +30,9 @@ class HeartTrackerPage extends StatefulWidget {
 }
 
 class _HeartTrackerPageState extends State<HeartTrackerPage> {
+  late final WearablesProvider _wearablesProvider;
+  Wearable? _wearable;
+  int _ppgTimestampExponent = -3;
   PpgFilter? _ppgFilter;
   Stream<(int, double)>? _displayPpgSignalStream;
   Stream<double?>? _heartRateStream;
@@ -38,22 +42,61 @@ class _HeartTrackerPageState extends State<HeartTrackerPage> {
   @override
   void initState() {
     super.initState();
+    _wearablesProvider = context.read<WearablesProvider>();
+    _wearablesProvider.addListener(_updateConnection);
     WidgetsBinding.instance.addPostFrameCallback((_) {
       if (!mounted) {
         return;
       }
-      _initializePipeline();
+      _updateConnection();
     });
   }
 
-  void _initializePipeline() {
-    final configProvider =
-        Provider.of<SensorConfigurationProvider>(context, listen: false);
-    _sensorConfigProvider = configProvider;
-    final ppgSensor = widget.ppgSensor;
-    final accelerometerSensor = widget.accelerometerSensor;
-    final opticalTemperatureSensor = widget.opticalTemperatureSensor;
+  void _updateConnection() {
+    final wearable = _wearablesProvider.wearables
+        .where((device) => device.deviceId == widget.wearable.deviceId)
+        .firstOrNull;
+    if (identical(wearable, _wearable)) {
+      return;
+    }
+    setState(() {
+      _ppgFilter?.dispose();
+      _ppgFilter = null;
+      _displayPpgSignalStream = null;
+      _heartRateStream = null;
+      _signalQualityStream = null;
+      _sensorConfigProvider = null;
+      _wearable = wearable;
+      if (wearable == null) {
+        return;
+      }
+      final sensors = wearable.requireCapability<SensorManager>().sensors;
+      Sensor? currentSensor(Sensor? previous) => sensors
+          .where((sensor) => sensor.sensorName == previous?.sensorName)
+          .firstOrNull;
+      final ppgSensor = currentSensor(widget.ppgSensor);
+      if (ppgSensor == null) {
+        return;
+      }
+      final configProvider =
+          _wearablesProvider.getSensorConfigurationProvider(wearable);
+      _sensorConfigProvider = configProvider;
+      _ppgTimestampExponent = ppgSensor.timestampExponent;
+      _initializePipeline(
+        configProvider,
+        ppgSensor,
+        currentSensor(widget.accelerometerSensor),
+        currentSensor(widget.opticalTemperatureSensor),
+      );
+    });
+  }
 
+  void _initializePipeline(
+    SensorConfigurationProvider configProvider,
+    Sensor ppgSensor,
+    Sensor? accelerometerSensor,
+    Sensor? opticalTemperatureSensor,
+  ) {
     final sampleFreq = _configureSensorForStreaming(
       ppgSensor,
       configProvider,
@@ -135,20 +178,15 @@ class _HeartTrackerPageState extends State<HeartTrackerPage> {
       timestampExponent: ppgSensor.timestampExponent,
     );
     ppgFilter.initialize();
-    if (!mounted) {
-      ppgFilter.dispose();
-      return;
-    }
-    setState(() {
-      _displayPpgSignalStream = ppgFilter.displaySignalStream;
-      _heartRateStream = ppgFilter.heartRateStream;
-      _signalQualityStream = ppgFilter.signalQualityStream;
-      _ppgFilter = ppgFilter;
-    });
+    _displayPpgSignalStream = ppgFilter.displaySignalStream;
+    _heartRateStream = ppgFilter.heartRateStream;
+    _signalQualityStream = ppgFilter.signalQualityStream;
+    _ppgFilter = ppgFilter;
   }
 
   @override
   void dispose() {
+    _wearablesProvider.removeListener(_updateConnection);
     final configProvider = _sensorConfigProvider;
     if (configProvider != null) {
       unawaited(configProvider.turnOffAllSensors());
@@ -372,16 +410,18 @@ class _HeartTrackerPageState extends State<HeartTrackerPage> {
       appBar: PlatformAppBar(
         title: PlatformText('Heart Tracker'),
       ),
-      body: displayPpgSignalStream == null ||
-              heartRateStream == null ||
-              signalQualityStream == null
-          ? const Center(child: PlatformCircularProgressIndicator())
-          : _buildContent(
-              context,
-              displayPpgSignalStream,
-              heartRateStream,
-              signalQualityStream,
-            ),
+      body: _wearable == null
+          ? const Center(child: Text('The selected wearable is disconnected.'))
+          : displayPpgSignalStream == null ||
+                  heartRateStream == null ||
+                  signalQualityStream == null
+              ? const Center(child: PlatformCircularProgressIndicator())
+              : _buildContent(
+                  context,
+                  displayPpgSignalStream,
+                  heartRateStream,
+                  signalQualityStream,
+                ),
     );
   }
 
@@ -392,10 +432,11 @@ class _HeartTrackerPageState extends State<HeartTrackerPage> {
     Stream<PpgSignalQuality> signalQualityStream,
   ) {
     return ListView(
+      key: ObjectKey(_wearable),
       padding: const EdgeInsets.fromLTRB(12, 12, 12, 20),
       children: [
         DeviceRow(
-          group: WearableDisplayGroup.single(wearable: widget.wearable),
+          group: WearableDisplayGroup.single(wearable: _wearable!),
         ),
         const SizedBox(height: 12),
         StreamBuilder<PpgSignalQuality>(
@@ -427,7 +468,7 @@ class _HeartTrackerPageState extends State<HeartTrackerPage> {
               '(0.5-3.2 Hz).',
           icon: Icons.show_chart_rounded,
           chartStream: displayPpgSignalStream,
-          timestampExponent: widget.ppgSensor.timestampExponent,
+          timestampExponent: _ppgTimestampExponent,
           fixedMeasureMin: null,
           fixedMeasureMax: null,
         ),