Add an "Auto-connect on startup" setting for Bluetooth devices, see #1339

Author: oliexdev

android_app/app/src/main/java/com/health/openscale/core/facade/SettingsFacade.kt

@@ -89,6 +89,7 @@ object SettingsPreferenceKeys {
     val SAVED_BLUETOOTH_SMART_ASSIGNMENT_ENABLED = booleanPreferencesKey("saved_bluetooth_smart_assignment_enabled")
     val SAVED_BLUETOOTH_TOLERANCE_PERCENT = intPreferencesKey("saved_bluetooth_tolerance_percent")
     val SAVED_BLUETOOTH_IGNORE_OUTSIDE_TOLERANCE = booleanPreferencesKey("saved_bluetooth_ignore_outside_tolerance")
+    val SAVED_BLUETOOTH_AUTO_CONNECT = booleanPreferencesKey("saved_bluetooth_auto_connect")
 
     // Settings for chart
     val CHART_SHOW_DATA_POINTS = booleanPreferencesKey("chart_show_data_points")
@@ -274,6 +275,9 @@ interface SettingsFacade {
     val selectedLbmFormula: Flow<LbmFormulaOption>
     suspend fun setSelectedLbmFormula(option: LbmFormulaOption)
 
+    val autoConnectOnStartup: Flow<Boolean>
+    suspend fun setAutoConnectOnStartup(enabled: Boolean)
+
     // Generic Settings Accessors
     /**
      * Observes a setting with the given key name and default value.
@@ -535,6 +539,7 @@ class SettingsFacadeImpl @Inject constructor(
             prefs.remove(SettingsPreferenceKeys.SAVED_BLUETOOTH_DEVICE_SERVICE_UUIDS)
             prefs.remove(SettingsPreferenceKeys.SAVED_BLUETOOTH_DEVICE_HANDLER_HINT)
             prefs.remove(SettingsPreferenceKeys.SAVED_BLUETOOTH_DEVICE_MANUFACTURER_DATA)
+            prefs.remove(SettingsPreferenceKeys.SAVED_BLUETOOTH_AUTO_CONNECT)
         }
     }
 
@@ -574,6 +579,15 @@ class SettingsFacadeImpl @Inject constructor(
         }
     }
 
+    override val autoConnectOnStartup: Flow<Boolean> = observeSetting(
+        SettingsPreferenceKeys.SAVED_BLUETOOTH_AUTO_CONNECT.name,
+        false
+    )
+
+    override suspend fun setAutoConnectOnStartup(enabled: Boolean) {
+        saveSetting(SettingsPreferenceKeys.SAVED_BLUETOOTH_AUTO_CONNECT.name, enabled)
+    }
+
     override val isSmartAssignmentEnabled: Flow<Boolean> = observeSetting(
         SettingsPreferenceKeys.SAVED_BLUETOOTH_SMART_ASSIGNMENT_ENABLED.name,
         false

android_app/app/src/main/java/com/health/openscale/ui/screen/settings/BluetoothDetailScreen.kt

@@ -33,6 +33,7 @@ import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.BluetoothConnected
 import androidx.compose.material.icons.filled.BugReport
 import androidx.compose.material.icons.filled.DeleteForever
 import androidx.compose.material.icons.filled.People
@@ -105,6 +106,7 @@ fun BluetoothDetailScreen(
     var tuningDropdownExpanded by remember { mutableStateOf(false) }
     val availableTuningProfiles = remember { TuningProfile.entries.toList() }
     var showToleranceDialog by remember { mutableStateOf(false) }
+    val autoConnectOnStartup by bluetoothViewModel.autoConnectOnStartup.collectAsStateWithLifecycle(false)
 
     if (showToleranceDialog) {
         NumberInputDialog(
@@ -194,6 +196,17 @@ fun BluetoothDetailScreen(
 
         // --- BLUETOOTH MEASUREMENT SECTION ---
         SettingsSectionTitle(title = stringResource(R.string.bluetooth_measurement_title))
+        SettingsRow(
+            modifier    = Modifier.padding(horizontal = 16.dp),
+            label       = stringResource(R.string.auto_connect_on_startup_title),
+            icon        = Icons.Default.BluetoothConnected,
+            onClick     = { scope.launch { bluetoothViewModel.setAutoConnectOnStartup(!autoConnectOnStartup) } }
+        ) {
+            Switch(
+                checked         = autoConnectOnStartup,
+                onCheckedChange = null,
+            )
+        }
         Card(modifier = Modifier.fillMaxWidth()) {
             Column(modifier = Modifier.padding(horizontal = 16.dp)) {
                 SettingsRow(
@@ -342,14 +355,15 @@ private fun SettingsSectionTitle(
  */
 @Composable
 private fun SettingsRow(
+    modifier: Modifier = Modifier,
     label: String,
     description: String? = null,
     icon: ImageVector? = null,
     onClick: (() -> Unit)? = null,
     content: @Composable () -> Unit
 ) {
     Box(
-        modifier = Modifier
+        modifier = modifier
             .fillMaxWidth()
             .then(if (onClick != null) Modifier.clickable(onClick = onClick) else Modifier)
     ) {

android_app/app/src/main/java/com/health/openscale/ui/screen/settings/BluetoothViewModel.kt

@@ -32,7 +32,10 @@ import dagger.hilt.android.lifecycle.HiltViewModel
 import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.SharedFlow
 import kotlinx.coroutines.flow.asSharedFlow
+import kotlinx.coroutines.flow.filter
+import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.withTimeoutOrNull
 import javax.inject.Inject
 
 /**
@@ -69,6 +72,7 @@ class BluetoothViewModel @Inject constructor(
     val isSmartAssignmentEnabled = settingsFacade.isSmartAssignmentEnabled
     val smartAssignmentTolerancePercent = settingsFacade.smartAssignmentTolerancePercent
     val smartAssignmentIgnoreOutsideTolerance = settingsFacade.smartAssignmentIgnoreOutsideTolerance
+    val autoConnectOnStartup = settingsFacade.autoConnectOnStartup
 
     fun setSmartAssignmentEnabled(enabled: Boolean) = viewModelScope.launch {
         settingsFacade.setSmartAssignmentEnabled(enabled)
@@ -82,6 +86,9 @@ class BluetoothViewModel @Inject constructor(
         settingsFacade.setSmartAssignmentIgnoreOutsideTolerance(ignore)
     }
 
+    fun setAutoConnectOnStartup(enabled: Boolean) = viewModelScope.launch {
+        settingsFacade.setAutoConnectOnStartup(enabled)
+    }
     // --- Snackbar events for UI ---
     private val _snackbarEvents = MutableSharedFlow<SnackbarEvent>(replay = 0, extraBufferCapacity = 1)
     val snackbarEvents: SharedFlow<SnackbarEvent> = _snackbarEvents.asSharedFlow()
@@ -92,6 +99,22 @@ class BluetoothViewModel @Inject constructor(
                 _snackbarEvents.emit(evt)
             }
         }
+
+        // Auto-connect on startup
+        viewModelScope.launch {
+            val enabled = settingsFacade.autoConnectOnStartup.first()
+            if (!enabled) return@launch
+
+            val device = withTimeoutOrNull(1_500) {
+                bt.savedDevice
+                    .filter { it != null }
+                    .first()
+            }
+
+            if (device != null) {
+                bt.attemptAutoConnectToSavedDevice()
+            }
+        }
     }
 
     // --- Delegated actions ---
@@ -122,8 +145,6 @@ class BluetoothViewModel @Inject constructor(
 
     fun clearAllErrors() = bt.clearErrors()
 
-    fun attemptAutoConnectToSavedScale() = bt.attemptAutoConnectToSavedDevice()
-
     fun provideUserInteractionFeedback(type: BluetoothEvent.UserInteractionType, feedbackData: Any) =
         bt.provideUserInteractionFeedback(type, feedbackData)
 

android_app/app/src/main/res/values-de/strings.xml

@@ -359,6 +359,7 @@
     <string name="tolerance_desc">Max. Gewichtsabweichung, um eine Messung automatisch einem Benutzer zuzuweisen.</string>
     <string name="developer_section_title">Entwickler</string>
     <string name="danger_zone_title">Gefahrenzone</string>
+    <string name="auto_connect_on_startup_title">Automatisch verbinden beim Start</string>
 
     <!-- Bluetooth Connector -->
     <string name="bluetooth_connector_connected_to">Verbunden mit %1$s</string>

android_app/app/src/main/res/values/strings.xml

@@ -364,6 +364,7 @@
     <string name="tolerance_desc">Max. weight deviation to automatically assign to a user.</string>
     <string name="developer_section_title">Developer</string>
     <string name="danger_zone_title">Danger Zone</string>
+    <string name="auto_connect_on_startup_title">Auto-connect on startup</string>
 
     <!-- Scale Configuration (generic, shown when a handler declares config fields) -->
     <string name="scale_configuration_title">Scale Configuration</string>