fix: optimize the logic for saving scroll position

app/build.gradle.kts

@@ -12,8 +12,8 @@ android {
         applicationId = "org.noxylva.lbjconsole"
         minSdk = 29
         targetSdk = 35
-        versionCode = 7
+        versionCode = 8
-        versionName = "0.0.7"
+        versionName = "0.0.8"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
     }

app/src/main/java/org/noxylva/lbjconsole/BLEClient.kt

@@ -276,6 +276,33 @@ class BLEClient(private val context: Context) : BluetoothGattCallback() {
         return isConnected
     }
     
+    @SuppressLint("MissingPermission")
+    fun checkActualConnectionState(): Boolean {
+        bluetoothGatt?.let { gatt ->
+            try {
+                val bluetoothManager = context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
+                val connectedDevices = bluetoothManager.getConnectedDevices(BluetoothProfile.GATT)
+                val isActuallyConnected = connectedDevices.any { it.address == deviceAddress }
+                
+                if (isActuallyConnected && !isConnected) {
+                    Log.d(TAG, "Found existing GATT connection, updating internal state")
+                    isConnected = true
+                    return true
+                } else if (!isActuallyConnected && isConnected) {
+                    Log.d(TAG, "GATT connection lost, updating internal state")
+                    isConnected = false
+                    return false
+                }
+                
+                return isActuallyConnected
+            } catch (e: Exception) {
+                Log.e(TAG, "Error checking actual connection state: ${e.message}")
+                return isConnected
+            }
+        }
+        return isConnected
+    }
+
 
     @SuppressLint("MissingPermission")
     fun disconnect() {

app/src/main/java/org/noxylva/lbjconsole/MainActivity.kt

@@ -52,6 +52,7 @@ import androidx.core.content.ContextCompat
 import androidx.core.content.FileProvider
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.Dispatchers
 import org.json.JSONObject
 import org.osmdroid.config.Configuration
 import org.noxylva.lbjconsole.model.TrainRecord
@@ -117,6 +118,7 @@ class MainActivity : ComponentActivity() {
     private var specifiedDeviceAddress by mutableStateOf<String?>(null)
     private var searchOrderList by mutableStateOf(listOf<String>())
     private var showDisconnectButton by mutableStateOf(false)
+    private var autoConnectEnabled by mutableStateOf(true)
     
     
     private val settingsPrefs by lazy { getSharedPreferences("app_settings", Context.MODE_PRIVATE) }
@@ -313,6 +315,12 @@ class MainActivity : ComponentActivity() {
                             saveSettings()
                             Log.d(TAG, "Set specified device address: $address")
                         },
+                        autoConnectEnabled = autoConnectEnabled,
+                        onAutoConnectEnabledChange = { enabled ->
+                            autoConnectEnabled = enabled
+                            saveSettings()
+                            Log.d(TAG, "Auto connect enabled: $enabled")
+                        },
                         
                         
                         latestRecord = latestRecord,
@@ -411,9 +419,11 @@ class MainActivity : ComponentActivity() {
                         deviceName = settingsDeviceName,
                         onDeviceNameChange = { newName -> settingsDeviceName = newName },
                         onApplySettings = {
-                            saveSettings()
+                            if (targetDeviceName != settingsDeviceName) {
-                            targetDeviceName = settingsDeviceName
+                                targetDeviceName = settingsDeviceName
-                            Log.d(TAG, "Applied settings deviceName=${settingsDeviceName}")
+                                Log.d(TAG, "Applied settings deviceName=${settingsDeviceName}")
+                                saveSettings()
+                            }
                         },
                         appVersion = getAppVersion(),
                         locoInfoUtil = locoInfoUtil,
@@ -615,6 +625,11 @@ class MainActivity : ComponentActivity() {
 
     
     private fun startAutoScanAndConnect() {
+        if (!autoConnectEnabled) {
+            Log.d(TAG, "Auto connect disabled, skipping auto scan")
+            return
+        }
+        
         Log.d(TAG, "Starting auto scan and connect")
         
         if (!hasBluetoothPermissions()) {
@@ -774,34 +789,39 @@ class MainActivity : ComponentActivity() {
             searchOrderStr.split(",").filter { it.isNotBlank() }
         }
         
+        autoConnectEnabled = settingsPrefs.getBoolean("auto_connect_enabled", true)
+        
         bleClient.setSpecifiedDeviceAddress(specifiedDeviceAddress)
         
-        Log.d(TAG, "Loaded settings deviceName=${settingsDeviceName} tab=${currentTab} specifiedDevice=${specifiedDeviceAddress} searchOrder=${searchOrderList.size}")
+        Log.d(TAG, "Loaded settings deviceName=${settingsDeviceName} tab=${currentTab} specifiedDevice=${specifiedDeviceAddress} searchOrder=${searchOrderList.size} autoConnect=${autoConnectEnabled}")
     }
     
     
     private fun saveSettings() {
-        val editor = settingsPrefs.edit()
+        lifecycleScope.launch(Dispatchers.IO) {
-            .putString("device_name", settingsDeviceName)
+            val editor = settingsPrefs.edit()
-            .putInt("current_tab", currentTab)
+                .putString("device_name", settingsDeviceName)
-            .putBoolean("history_edit_mode", historyEditMode)
+                .putInt("current_tab", currentTab)
-            .putString("history_selected_records", historySelectedRecords.joinToString(","))
+                .putBoolean("history_edit_mode", historyEditMode)
-            .putString("history_expanded_states", historyExpandedStates.map { "${it.key}:${it.value}" }.joinToString(";"))
+                .putString("history_selected_records", historySelectedRecords.joinToString(","))
-            .putInt("history_scroll_position", historyScrollPosition)
+                .putString("history_expanded_states", historyExpandedStates.map { "${it.key}:${it.value}" }.joinToString(";"))
-            .putInt("history_scroll_offset", historyScrollOffset)
+                .putInt("history_scroll_position", historyScrollPosition)
-            .putInt("settings_scroll_position", settingsScrollPosition)
+                .putInt("history_scroll_offset", historyScrollOffset)
-            .putFloat("map_zoom_level", mapZoomLevel.toFloat())
+                .putInt("settings_scroll_position", settingsScrollPosition)
-            .putBoolean("map_railway_visible", mapRailwayLayerVisible)
+                .putFloat("map_zoom_level", mapZoomLevel.toFloat())
-            .putString("specified_device_address", specifiedDeviceAddress)
+                .putBoolean("map_railway_visible", mapRailwayLayerVisible)
-            .putString("search_order_list", searchOrderList.joinToString(","))
+                .putString("specified_device_address", specifiedDeviceAddress)
+                .putString("search_order_list", searchOrderList.joinToString(","))
+                .putBoolean("auto_connect_enabled", autoConnectEnabled)
                 
-        mapCenterPosition?.let { (lat, lon) ->
+            mapCenterPosition?.let { (lat, lon) ->
-            editor.putFloat("map_center_lat", lat.toFloat())
+                editor.putFloat("map_center_lat", lat.toFloat())
-            editor.putFloat("map_center_lon", lon.toFloat())
+                editor.putFloat("map_center_lon", lon.toFloat())
+            }
+            
+            editor.apply()
+            Log.d(TAG, "Saved settings deviceName=${settingsDeviceName} tab=${currentTab} mapCenter=${mapCenterPosition} zoom=${mapZoomLevel}")
         }
-        
-        editor.apply()
-        Log.d(TAG, "Saved settings deviceName=${settingsDeviceName} tab=${currentTab} mapCenter=${mapCenterPosition} zoom=${mapZoomLevel}")
     }
     
     override fun onResume() {
@@ -810,12 +830,20 @@ class MainActivity : ComponentActivity() {
         
         bleClient.setHighFrequencyReconnect(true)
         
-        if (hasBluetoothPermissions() && !bleClient.isConnected()) {
+        if (hasBluetoothPermissions()) {
-            Log.d(TAG, "App resumed and not connected, starting auto scan")
+            val actuallyConnected = bleClient.checkActualConnectionState()
-            startAutoScanAndConnect()
+            
-        } else if (bleClient.isConnected()) {
+            if (actuallyConnected) {
-            showDisconnectButton = true
+                showDisconnectButton = true
-            deviceStatus = "已连接"
+                deviceStatus = "已连接"
+                Log.d(TAG, "App resumed - connection verified")
+            } else if (autoConnectEnabled) {
+                Log.d(TAG, "App resumed and not connected, starting auto scan")
+                startAutoScanAndConnect()
+            } else {
+                deviceStatus = "未连接"
+                showDisconnectButton = false
+            }
         }
     }
     
@@ -847,6 +875,8 @@ fun MainContent(
     specifiedDeviceAddress: String?,
         searchOrderList: List<String>,
         onSpecifiedDeviceSelected: (String?) -> Unit,
+    autoConnectEnabled: Boolean,
+    onAutoConnectEnabledChange: (Boolean) -> Unit,
     
     
     latestRecord: TrainRecord?,
@@ -1118,7 +1148,9 @@ fun MainContent(
                     onScrollPositionChange = onSettingsScrollPositionChange,
                     specifiedDeviceAddress = specifiedDeviceAddress,
                     searchOrderList = searchOrderList,
-                    onSpecifiedDeviceSelected = onSpecifiedDeviceSelected
+                    onSpecifiedDeviceSelected = onSpecifiedDeviceSelected,
+                    autoConnectEnabled = autoConnectEnabled,
+                    onAutoConnectEnabledChange = onAutoConnectEnabledChange
                 )
                 3 -> MapScreen(
                     records = if (allRecords.isNotEmpty()) {

app/src/main/java/org/noxylva/lbjconsole/NotificationService.kt

@@ -8,11 +8,14 @@ import android.content.Intent
 import android.content.SharedPreferences
 import android.os.Build
 import android.util.Log
+import android.view.View
+import android.widget.RemoteViews
 import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
 import org.json.JSONObject
 import org.noxylva.lbjconsole.model.TrainRecord
 
+
 class NotificationService(private val context: Context) {
     companion object {
         const val TAG = "NotificationService"
@@ -86,12 +89,7 @@ class NotificationService(private val context: Context) {
                 PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
             )
 
-            val directionText = when (trainRecord.direction) {
+            val remoteViews = RemoteViews(context.packageName, R.layout.notification_train_record)
-                1 -> "下行"
-                3 -> "上行"
-                else -> "未知"
-            }
-
             val trainDisplay = if (isValidValue(trainRecord.lbjClass) && isValidValue(trainRecord.train)) {
                 "${trainRecord.lbjClass.trim()}${trainRecord.train.trim()}"
             } else if (isValidValue(trainRecord.lbjClass)) {
@@ -99,26 +97,83 @@ class NotificationService(private val context: Context) {
             } else if (isValidValue(trainRecord.train)) {
                 trainRecord.train.trim()
             } else "列车"
+            remoteViews.setTextViewText(R.id.notification_train_number, trainDisplay)
             
-            val title = trainDisplay
+            val directionText = when (trainRecord.direction) {
-            val content = buildString {
+                1 -> "下"
-                append(directionText)
+                3 -> "上"
-                if (isValidValue(trainRecord.route)) {
+                else -> ""
-                    append("\n线路: ${trainRecord.route.trim()}")
-                }
-                if (isValidValue(trainRecord.speed)) {
-                    append("\n速度: ${trainRecord.speed.trim()} km/h")
-                }
-                if (isValidValue(trainRecord.position)) {
-                    append("\n位置: ${trainRecord.position.trim()} km")
-                }
             }
+            if (directionText.isNotEmpty()) {
+                remoteViews.setTextViewText(R.id.notification_direction, directionText)
+                remoteViews.setViewVisibility(R.id.notification_direction, View.VISIBLE)
+            } else {
+                remoteViews.setViewVisibility(R.id.notification_direction, View.GONE)
+            }
+            
+            val locoInfo = when {
+                isValidValue(trainRecord.locoType) && isValidValue(trainRecord.loco) -> {
+                    val shortLoco = if (trainRecord.loco.length > 5) {
+                        trainRecord.loco.takeLast(5)
+                    } else {
+                        trainRecord.loco
+                    }
+                    "${trainRecord.locoType}-${shortLoco}"
+                }
+                isValidValue(trainRecord.locoType) -> trainRecord.locoType
+                isValidValue(trainRecord.loco) -> trainRecord.loco
+                else -> ""
+            }
+            if (locoInfo.isNotEmpty()) {
+                remoteViews.setTextViewText(R.id.notification_loco_info, locoInfo)
+                remoteViews.setViewVisibility(R.id.notification_loco_info, View.VISIBLE)
+            } else {
+                remoteViews.setViewVisibility(R.id.notification_loco_info, View.GONE)
+            }
+            
+            if (isValidValue(trainRecord.route)) {
+                remoteViews.setTextViewText(R.id.notification_route, trainRecord.route.trim())
+                remoteViews.setViewVisibility(R.id.notification_route, View.VISIBLE)
+            } else {
+                remoteViews.setViewVisibility(R.id.notification_route, View.GONE)
+            }
+            
+            if (isValidValue(trainRecord.position)) {
+                remoteViews.setTextViewText(R.id.notification_position, "${trainRecord.position.trim()}K")
+                remoteViews.setViewVisibility(R.id.notification_position, View.VISIBLE)
+            } else {
+                remoteViews.setViewVisibility(R.id.notification_position, View.GONE)
+            }
+            
+            if (isValidValue(trainRecord.speed)) {
+                remoteViews.setTextViewText(R.id.notification_speed, "${trainRecord.speed.trim()} km/h")
+                remoteViews.setViewVisibility(R.id.notification_speed, View.VISIBLE)
+            } else {
+                remoteViews.setViewVisibility(R.id.notification_speed, View.GONE)
+            }
+            
+            remoteViews.setOnClickPendingIntent(R.id.notification_train_number, pendingIntent)
+
+            val summaryParts = mutableListOf<String>()
+            
+            val routeAndDirection = when {
+                isValidValue(trainRecord.route) && directionText.isNotEmpty() -> "${trainRecord.route.trim()}${directionText}行"
+                isValidValue(trainRecord.route) -> trainRecord.route.trim()
+                directionText.isNotEmpty() -> "${directionText}行"
+                else -> null
+            }
+            
+            routeAndDirection?.let { summaryParts.add(it) }
+            if (locoInfo.isNotEmpty()) summaryParts.add(locoInfo)
+            
+            val summaryText = summaryParts.joinToString(" • ")
 
             val notification = NotificationCompat.Builder(context, CHANNEL_ID)
                 .setSmallIcon(R.drawable.ic_notification)
-                .setContentTitle(title)
+                .setContentTitle(trainDisplay)
-                .setContentText(content)
+                .setContentText(summaryText)
-                .setStyle(NotificationCompat.BigTextStyle().bigText(content))
+                .setCustomContentView(remoteViews)
+                .setCustomBigContentView(remoteViews)
                 .setPriority(NotificationCompat.PRIORITY_DEFAULT)
                 .setContentIntent(pendingIntent)
                 .setAutoCancel(true)
@@ -131,7 +186,7 @@ class NotificationService(private val context: Context) {
             }
 
             notificationManager.notify(notificationId, notification)
-            Log.d(TAG, "Notification sent for train: ${trainRecord.train}")
+            Log.d(TAG, "Custom notification sent for train: ${trainRecord.train}")
 
         } catch (e: Exception) {
             Log.e(TAG, "Failed to show notification: ${e.message}", e)

app/src/main/java/org/noxylva/lbjconsole/model/MergeSettings.kt

@@ -7,9 +7,10 @@ data class MergeSettings(
 )
 
 enum class GroupBy(val displayName: String) {
-    TRAIN_AND_LOCO("车次号+机车号"),
+    TRAIN_ONLY("车次号"),
-    TRAIN_ONLY("仅车次号"),
+    LOCO_ONLY("机车号"),
-    LOCO_ONLY("仅机车号")
+    TRAIN_OR_LOCO("车次号或机车号"),
+    TRAIN_AND_LOCO("车次号与机车号")
 }
 
 enum class TimeWindow(val displayName: String, val seconds: Long?) {
@@ -23,14 +24,6 @@ enum class TimeWindow(val displayName: String, val seconds: Long?) {
 
 fun generateGroupKey(record: TrainRecord, groupBy: GroupBy): String? {
     return when (groupBy) {
-        GroupBy.TRAIN_AND_LOCO -> {
-            val train = record.train.trim()
-            val loco = record.loco.trim()
-            if (train.isNotEmpty() && train != "<NUL>" && 
-                loco.isNotEmpty() && loco != "<NUL>") {
-                "${train}_${loco}"
-            } else null
-        }
         GroupBy.TRAIN_ONLY -> {
             val train = record.train.trim()
             if (train.isNotEmpty() && train != "<NUL>") train else null
@@ -39,5 +32,22 @@ fun generateGroupKey(record: TrainRecord, groupBy: GroupBy): String? {
             val loco = record.loco.trim()
             if (loco.isNotEmpty() && loco != "<NUL>") loco else null
         }
+        GroupBy.TRAIN_OR_LOCO -> {
+            val train = record.train.trim()
+            val loco = record.loco.trim()
+            when {
+                train.isNotEmpty() && train != "<NUL>" -> train
+                loco.isNotEmpty() && loco != "<NUL>" -> loco
+                else -> null
+            }
+        }
+        GroupBy.TRAIN_AND_LOCO -> {
+            val train = record.train.trim()
+            val loco = record.loco.trim()
+            if (train.isNotEmpty() && train != "<NUL>" && 
+                loco.isNotEmpty() && loco != "<NUL>") {
+                "${train}_${loco}"
+            } else null
+        }
     }
 }

app/src/main/java/org/noxylva/lbjconsole/model/TrainRecordManager.kt

@@ -234,26 +234,79 @@ class TrainRecordManager(private val context: Context) {
     }
     
     private fun processRecordsForMerging(records: List<TrainRecord>, settings: MergeSettings): List<MergedTrainRecord> {
-        val groupedRecords = mutableMapOf<String, MutableList<TrainRecord>>()
         val currentTime = Date()
+        val validRecords = records.filter { record ->
+            settings.timeWindow.seconds?.let { windowSeconds ->
+                (currentTime.time - record.timestamp.time) / 1000 <= windowSeconds
+            } ?: true
+        }
+        
+        return when (settings.groupBy) {
+            GroupBy.TRAIN_OR_LOCO -> processTrainOrLocoMerging(validRecords)
+            else -> {
+                val groupedRecords = mutableMapOf<String, MutableList<TrainRecord>>()
+                validRecords.forEach { record ->
+                    val groupKey = generateGroupKey(record, settings.groupBy)
+                    if (groupKey != null) {
+                        groupedRecords.getOrPut(groupKey) { mutableListOf() }.add(record)
+                    }
+                }
+                
+                groupedRecords.mapNotNull { (groupKey, groupRecords) ->
+                    if (groupRecords.size >= 2) {
+                        val sortedRecords = groupRecords.sortedBy { it.timestamp }
+                        val latestRecord = sortedRecords.maxByOrNull { it.timestamp }!!
+                        MergedTrainRecord(
+                            groupKey = groupKey,
+                            records = sortedRecords,
+                            latestRecord = latestRecord
+                        )
+                    } else null
+                }.sortedByDescending { it.latestRecord.timestamp }
+            }
+        }
+    }
+    
+    private fun processTrainOrLocoMerging(records: List<TrainRecord>): List<MergedTrainRecord> {
+        val groups = mutableListOf<MutableList<TrainRecord>>()
         
         records.forEach { record ->
-            val groupKey = generateGroupKey(record, settings.groupBy)
+            val train = record.train.trim()
-            if (groupKey != null) {
+            val loco = record.loco.trim()
-                val withinTimeWindow = settings.timeWindow.seconds?.let { windowSeconds ->
-                    (currentTime.time - record.timestamp.time) / 1000 <= windowSeconds
-                } ?: true
             
-                if (withinTimeWindow) {
+            if ((train.isEmpty() || train == "<NUL>") && (loco.isEmpty() || loco == "<NUL>")) {
-                    groupedRecords.getOrPut(groupKey) { mutableListOf() }.add(record)
+                return@forEach
+            }
+            
+            var foundGroup: MutableList<TrainRecord>? = null
+            
+            for (group in groups) {
+                val shouldMerge = group.any { existingRecord ->
+                    val existingTrain = existingRecord.train.trim()
+                    val existingLoco = existingRecord.loco.trim()
+                    
+                    (train.isNotEmpty() && train != "<NUL>" && train == existingTrain) ||
+                    (loco.isNotEmpty() && loco != "<NUL>" && loco == existingLoco)
                 }
+                
+                if (shouldMerge) {
+                    foundGroup = group
+                    break
+                }
+            }
+            
+            if (foundGroup != null) {
+                foundGroup.add(record)
+            } else {
+                groups.add(mutableListOf(record))
             }
         }
         
-        return groupedRecords.mapNotNull { (groupKey, groupRecords) ->
+        return groups.mapNotNull { groupRecords ->
             if (groupRecords.size >= 2) {
                 val sortedRecords = groupRecords.sortedBy { it.timestamp }
                 val latestRecord = sortedRecords.maxByOrNull { it.timestamp }!!
+                val groupKey = "${latestRecord.train}_OR_${latestRecord.loco}"
                 MergedTrainRecord(
                     groupKey = groupKey,
                     records = sortedRecords,

app/src/main/java/org/noxylva/lbjconsole/ui/screens/HistoryScreen.kt

@@ -1,5 +1,6 @@
 package org.noxylva.lbjconsole.ui.screens
 
+import android.util.Log
 import androidx.compose.foundation.ExperimentalFoundationApi
 import androidx.compose.foundation.combinedClickable
 import androidx.compose.foundation.background
@@ -862,6 +863,7 @@ fun HistoryScreen(
 ) {
 
     val refreshKey = latestRecord?.timestamp?.time ?: 0
+    var wasAtTopBeforeUpdate by remember { mutableStateOf(false) }
 
     var isInEditMode by remember(editMode) { mutableStateOf(editMode) }
     val selectedRecordsList = remember(selectedRecords) { 
@@ -942,6 +944,22 @@ fun HistoryScreen(
         }
     }
     
+    LaunchedEffect(listState.firstVisibleItemIndex, listState.firstVisibleItemScrollOffset) {
+        if (!isInEditMode && filteredRecords.isNotEmpty()) {
+            wasAtTopBeforeUpdate = listState.firstVisibleItemIndex == 0 && listState.firstVisibleItemScrollOffset <= 100
+        }
+    }
+
+    LaunchedEffect(refreshKey) {
+        if (refreshKey > 0 && !isInEditMode && filteredRecords.isNotEmpty() && wasAtTopBeforeUpdate) {
+            try {
+                listState.animateScrollToItem(0, 0)
+            } catch (e: Exception) {
+                listState.scrollToItem(0, 0)
+            }
+        }
+    }
+
     Box(modifier = Modifier.fillMaxSize()) {
         Column(modifier = Modifier.fillMaxSize()) {
             Box(

app/src/main/java/org/noxylva/lbjconsole/ui/screens/SettingsScreen.kt

@@ -15,6 +15,7 @@ import androidx.compose.ui.platform.LocalUriHandler
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
 import org.noxylva.lbjconsole.model.MergeSettings
 import org.noxylva.lbjconsole.model.GroupBy
 import org.noxylva.lbjconsole.model.TimeWindow
@@ -38,23 +39,24 @@ fun SettingsScreen(
     onScrollPositionChange: (Int) -> Unit = {},
     specifiedDeviceAddress: String? = null,
     searchOrderList: List<String> = emptyList(),
-    onSpecifiedDeviceSelected: (String?) -> Unit = {}
+    onSpecifiedDeviceSelected: (String?) -> Unit = {},
+    autoConnectEnabled: Boolean = true,
+    onAutoConnectEnabledChange: (Boolean) -> Unit = {}
 ) {
     val uriHandler = LocalUriHandler.current
     val scrollState = rememberScrollState()
     
     LaunchedEffect(scrollPosition) {
-        scrollState.scrollTo(scrollPosition)
+        if (scrollState.value != scrollPosition) {
+            scrollState.scrollTo(scrollPosition)
+        }
     }
     
     LaunchedEffect(scrollState.value) {
+        delay(50)
         onScrollPositionChange(scrollState.value)
     }
     
-    LaunchedEffect(deviceName) {
-        onApplySettings()
-    }
-    
     Column(
         modifier = Modifier
             .fillMaxSize()
@@ -196,12 +198,13 @@ fun SettingsScreen(
                 }
                 
                 val context = LocalContext.current
-                var backgroundServiceEnabled by remember {
+                val notificationService = remember(context) { NotificationService(context) }
+                
+                var backgroundServiceEnabled by remember(context) {
                     mutableStateOf(SettingsActivity.isBackgroundServiceEnabled(context))
                 }
                 
-                val notificationService = remember { NotificationService(context) }
+                var notificationEnabled by remember(context, notificationService) {
-                var notificationEnabled by remember {
                     mutableStateOf(notificationService.isNotificationEnabled())
                 }
                 
@@ -262,6 +265,29 @@ fun SettingsScreen(
                         }
                     )
                 }
+                
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.SpaceBetween,
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Column {
+                        Text(
+                            "自动连接",
+                            style = MaterialTheme.typography.bodyMedium,
+                            fontWeight = FontWeight.Medium
+                        )
+                        Text(
+                            "自动连接蓝牙设备",
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant
+                        )
+                    }
+                    Switch(
+                        checked = autoConnectEnabled,
+                        onCheckedChange = onAutoConnectEnabledChange
+                    )
+                }
             }
         }
         

app/src/main/res/layout/notification_train_record.xml

@@ -0,0 +1,99 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:padding="4dp"
+    android:background="@android:color/transparent">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:layout_marginBottom="4dp"
+        android:gravity="center_vertical">
+
+        <LinearLayout
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:orientation="horizontal"
+            android:gravity="center_vertical">
+
+            <TextView
+                android:id="@+id/notification_train_number"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="G1234"
+                android:textSize="16sp"
+                android:textStyle="bold"
+                android:textColor="?android:attr/textColorPrimary"
+                android:layout_marginEnd="4dp" />
+
+            <TextView
+                android:id="@+id/notification_direction"
+                android:layout_width="16dp"
+                android:layout_height="16dp"
+                android:text="下"
+                android:textSize="10sp"
+                android:textStyle="bold"
+                android:textColor="@android:color/white"
+                android:background="@android:color/black"
+                android:gravity="center"
+                android:visibility="gone" />
+
+        </LinearLayout>
+
+        <TextView
+            android:id="@+id/notification_loco_info"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="CRH380D-1234"
+            android:textSize="12sp"
+            android:textColor="?android:attr/textColorPrimary" />
+
+    </LinearLayout>
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical">
+
+        <LinearLayout
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:orientation="horizontal"
+            android:gravity="center_vertical">
+
+            <TextView
+                android:id="@+id/notification_route"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="京沪高铁"
+                android:textSize="14sp"
+                android:textColor="?android:attr/textColorPrimary"
+                android:layout_marginEnd="4dp" />
+
+            <TextView
+                android:id="@+id/notification_position"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="1234K"
+                android:textSize="14sp"
+                android:textColor="?android:attr/textColorPrimary" />
+
+        </LinearLayout>
+
+        <TextView
+            android:id="@+id/notification_speed"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="300 km/h"
+            android:textSize="14sp"
+            android:textColor="?android:attr/textColorPrimary" />
+
+    </LinearLayout>
+
+</LinearLayout>