This commit introduces a new feature that groups snackbar messages when multiple measurements are saved in quick succession. Instead of displaying individual "Measurement saved" messages for each, a single message like "Saved X measurements" will now be shown.

Additionally, this commit:
- Improves the snackbar display logic to prevent duplicate messages and introduces a debounce mechanism.
- Enhances the Overview screen's scrolling behavior to smoothly scroll to the top when new items are added, and also improves the scroll behavior when tapping on chart points.

android_app/app/src/main/java/com/health/openscale/core/service/BleConnector.kt

@@ -42,8 +42,10 @@ import kotlinx.coroutines.flow.SharedFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asSharedFlow
 import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.debounce
 import kotlinx.coroutines.flow.firstOrNull
 import kotlinx.coroutines.launch
+import java.util.concurrent.atomic.AtomicInteger
 
 /**
  * Manages Bluetooth connections to scale devices, handling the connection lifecycle,
@@ -102,6 +104,38 @@ class BleConnector(
     private var communicatorJob: Job? = null // Job for observing events from the activeCommunicator.
     private var disconnectTimeoutJob: Job? = null // Job for handling disconnect timeouts.
 
+    private val savedBurstSignal = MutableSharedFlow<Unit>(replay = 0, extraBufferCapacity = 64)
+    private val pendingSavedCount = AtomicInteger(0)
+    @Volatile private var lastSavedArgs: List<Any> = emptyList()
+
+    init {
+        scope.launch {
+            savedBurstSignal
+                .debounce(700)
+                .collect {
+                    val count = pendingSavedCount.getAndSet(0)
+                    if (count <= 0) return@collect
+
+                    if (count == 1) {
+                        _snackbarEvents.emit(
+                            SnackbarEvent(
+                                messageResId = R.string.bluetooth_connector_measurement_saved,
+                                messageFormatArgs = lastSavedArgs
+                            )
+                        )
+                    } else {
+                        _snackbarEvents.tryEmit(
+                            SnackbarEvent(
+                                messageResId = R.string.saved_measurements_message,
+                                messageFormatArgs = listOf(count)
+                            )
+                        )
+                    }
+                }
+        }
+    }
+
+
     /**
      * Attempts to connect to the specified Bluetooth device.
      * This function is suspendable and performs operations in the [scope] provided during construction.
@@ -185,7 +219,6 @@ class BleConnector(
                                 // but confirm here for safety.
                                 _connectedDeviceAddress.value = connectedDeviceInfo.address
                                 _connectedDeviceName.value = connectedDeviceInfo.name
-                                _snackbarEvents.tryEmit(SnackbarEvent(messageResId = R.string.bluetooth_connector_connected_to, messageFormatArgs = listOf(deviceDisplayName)))
                                 _connectionError.value = null // Clear any errors on successful connection.
                                 LogManager.i(TAG, "Successfully connected to $deviceDisplayName via adapter's isConnected flow.")
                                 disconnectTimeoutJob?.cancel() // Successfully connected, timeout no longer needed.
@@ -429,7 +462,9 @@ class BleConnector(
                 finalValues.forEach { databaseRepository.insertMeasurementValue(it) }
 
                 LogManager.i(TAG, "Measurement from $deviceName for User $currentAppUserId saved (ID: $measurementId). Values: ${finalValues.size}")
-                _snackbarEvents.tryEmit(SnackbarEvent(messageResId = R.string.bluetooth_connector_measurement_saved, messageFormatArgs = listOf(measurementData.weight, deviceName)))
+                pendingSavedCount.incrementAndGet()
+                lastSavedArgs = listOf(measurementData.weight, deviceName)
+                savedBurstSignal.tryEmit(Unit)
             } catch (e: Exception) {
                 LogManager.e(TAG, "Error saving measurement from $deviceName.", e)
                 _snackbarEvents.tryEmit(SnackbarEvent(messageResId = R.string.bluetooth_connector_measurement_save_error, messageFormatArgs = listOf(deviceName)))

android_app/app/src/main/java/com/health/openscale/ui/navigation/AppNavigation.kt

@@ -130,6 +130,8 @@ import com.health.openscale.ui.screen.statistics.StatisticsScreen
 import com.health.openscale.ui.theme.Black
 import com.health.openscale.ui.theme.Blue
 import com.health.openscale.ui.theme.White
+import kotlinx.coroutines.flow.debounce
+import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.launch
 
 /**
@@ -202,17 +204,25 @@ fun AppNavigation(sharedViewModel: SharedViewModel) {
                 sharedViewModel.snackbarEvents,
                 settingsViewModel.snackbarEvents,
                 bluetoothViewModel.snackbarEvents
-            ).collect { evt ->
+            )
+            .distinctUntilChanged { a, b ->
+                    a.messageResId == b.messageResId && a.message == b.message
+            }
+            .debounce(150)
+            .collect { evt ->
                 val msg = evt.message ?: context.getString(
                     requireNotNull(evt.messageResId),
                     *evt.messageFormatArgs.toTypedArray()
                 )
                 val action = evt.actionLabel ?: evt.actionLabelResId?.let { context.getString(it) }
-                val res = snackbarHostState.showSnackbar(
-                    message = msg,
-                    actionLabel = action,
-                    duration = evt.duration
-                )
+                val res = snackbarHostState.run {
+                    currentSnackbarData?.dismiss()
+                    showSnackbar(
+                        message = msg,
+                        actionLabel = action,
+                        duration = evt.duration
+                    )
+                }
                 if (res == SnackbarResult.ActionPerformed) evt.onAction?.invoke()
             }
         }

android_app/app/src/main/java/com/health/openscale/ui/screen/overview/OverviewScreen.kt

@@ -45,6 +45,7 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.LazyListState
 import androidx.compose.foundation.lazy.itemsIndexed
 import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.material.icons.Icons
@@ -120,6 +121,10 @@ import com.health.openscale.ui.screen.components.LineChart
 import com.health.openscale.ui.screen.components.provideFilterTopBarAction
 import com.health.openscale.ui.shared.TopBarAction
 import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.collectLatest
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.drop
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
 import java.text.DateFormat
 import java.text.SimpleDateFormat
@@ -471,6 +476,14 @@ fun OverviewScreen(
                         )
                     }
                 } else {
+                    val topId = items.firstOrNull()?.measurementWithValues?.measurement?.id
+                    LaunchedEffect(topId) {
+                        if (topId != null && !listState.isScrollInProgress) {
+                            delay(60)
+                            listState.smartScrollTo(0)
+                        }
+                    }
+
                     // Chart
                     Box(modifier = Modifier.fillMaxWidth()) {
                         LineChart(
@@ -488,9 +501,8 @@ fun OverviewScreen(
                                     ?.let { (targetIndex, mwv) ->
                                         val targetId = mwv.measurement.id
                                         scope.launch {
-                                            listState.animateScrollToItem(
-                                                index = targetIndex,
-                                                scrollOffset = 0
+                                            listState.smartScrollTo(
+                                                index = targetIndex
                                             )
                                             highlightedMeasurementId = targetId
                                             delay(600)
@@ -542,6 +554,11 @@ fun OverviewScreen(
     }
 }
 
+suspend fun LazyListState.smartScrollTo(index: Int) {
+    val dist = kotlin.math.abs(firstVisibleItemIndex - index)
+    if (dist > 20) scrollToItem(index) else animateScrollToItem(index)
+}
+
 /**
  * A Composable card displayed when no user is currently selected/active.
  * It prompts the user to add or select a user.

android_app/app/src/main/java/com/health/openscale/ui/shared/SharedViewModel.kt

@@ -105,6 +105,8 @@ class SharedViewModel @Inject constructor(
         actionLabel: String? = null,
         onAction: (() -> Unit)? = null
     ) {
+        if (message == null && messageResId == null) return
+
         viewModelScope.launch {
             _snackbarEvents.emit(
                 SnackbarEvent(

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

@@ -508,4 +508,6 @@
     <string name="dialog_bt_error_loading_user_list_format">Fehler: Benutzerdaten konnten nicht korrekt geladen werden.</string>
     <string name="dialog_bt_select_user_prompt">Bitte einen Benutzer auswählen.</string>
     <string name="dialog_bt_enter_valid_code_prompt">Bitte einen gültigen Code eingeben.</string>
+    <string name="saved_measurements_message">%1$d Messungen gespeichert</string>
+
 </resources>

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

@@ -508,4 +508,7 @@
     <string name="dialog_bt_select_user_prompt">Please select a user.</string>
     <string name="dialog_bt_enter_valid_code_prompt">Please enter a valid code.</string>
 
+    <string name="saved_measurements_message">Saved %1$d measurements</string>
+
+
 </resources>