feat: add background keep-alive service and related setting functions

app/build.gradle.kts

@@ -81,7 +81,7 @@ dependencies {
     debugImplementation(libs.androidx.ui.test.manifest)
     implementation("org.json:json:20231013")
     implementation("androidx.compose.material:material-icons-extended:1.5.4")
-    
+    implementation("androidx.appcompat:appcompat:1.6.1")
     
     implementation("org.osmdroid:osmdroid-android:6.1.16")
     implementation("org.osmdroid:osmdroid-mapsforge:6.1.16")

app/src/main/AndroidManifest.xml

@@ -11,6 +11,8 @@
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
     <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+    <uses-permission android:name="android.permission.WAKE_LOCK" />
     
     <uses-feature android:name="android.hardware.bluetooth_le" android:required="true"/>
 
@@ -22,14 +24,14 @@
         android:label="@string/app_name"
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
-        android:theme="@style/Theme.LBJReceiver"
+        android:theme="@style/Theme.LBJConsole"
         android:usesCleartextTraffic="true"
         tools:targetApi="31">
         <activity
             android:name=".MainActivity"
             android:exported="true"
             android:label="@string/app_name"
-            android:theme="@style/Theme.LBJReceiver">
+            android:theme="@style/Theme.LBJConsole">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
@@ -37,6 +39,19 @@
             </intent-filter>
         </activity>
         
+        <activity
+            android:name=".SettingsActivity"
+            android:exported="false"
+            android:label="Settings"
+            android:parentActivityName=".MainActivity"
+            android:theme="@style/Theme.LBJConsole" />
+        
+        <service
+            android:name=".BackgroundService"
+            android:enabled="true"
+            android:exported="false"
+            android:foregroundServiceType="dataSync" />
+        
         <provider
             android:name="androidx.core.content.FileProvider"
             android:authorities="${applicationId}.provider"

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

@@ -437,6 +437,7 @@ class BLEClient(private val context: Context) : BluetoothGattCallback() {
                 try {
                     gatt.close()
                     bluetoothGatt = null
+                    bluetoothLeScanner = null
 
                     deviceAddress?.let { address ->
                         if (autoReconnect) {
@@ -819,6 +820,7 @@ class BLEClient(private val context: Context) : BluetoothGattCallback() {
             }
         }
         bluetoothGatt = null
+        bluetoothLeScanner = null
         deviceAddress = null
         connectionAttempts = 0
         

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

@@ -0,0 +1,123 @@
+package org.noxylva.lbjconsole
+
+import android.app.Notification
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.app.Service
+import android.content.Context
+import android.content.Intent
+import android.os.Build
+import android.os.IBinder
+import android.os.PowerManager
+import androidx.core.app.NotificationCompat
+
+class BackgroundService : Service() {
+    
+    companion object {
+        private const val NOTIFICATION_ID = 1001
+        private const val CHANNEL_ID = "background_service_channel"
+        private const val CHANNEL_NAME = "Background Service"
+        
+        fun startService(context: Context) {
+            try {
+                val intent = Intent(context, BackgroundService::class.java)
+                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+                    context.startForegroundService(intent)
+                } else {
+                    context.startService(intent)
+                }
+            } catch (e: Exception) {
+                // Service start failed, ignore silently
+            }
+        }
+        
+        fun stopService(context: Context) {
+            val intent = Intent(context, BackgroundService::class.java)
+            context.stopService(intent)
+        }
+    }
+    
+    private var wakeLock: PowerManager.WakeLock? = null
+    
+    override fun onCreate() {
+        super.onCreate()
+        createNotificationChannel()
+        acquireWakeLock()
+    }
+    
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        try {
+            val notification = createNotification()
+            startForeground(NOTIFICATION_ID, notification)
+        } catch (e: Exception) {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+                stopSelf()
+                return START_NOT_STICKY
+            }
+        }
+        return START_STICKY
+    }
+    
+    override fun onDestroy() {
+        super.onDestroy()
+        releaseWakeLock()
+    }
+    
+    override fun onBind(intent: Intent?): IBinder? {
+        return null
+    }
+    
+    private fun createNotificationChannel() {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            val channel = NotificationChannel(
+                CHANNEL_ID,
+                CHANNEL_NAME,
+                NotificationManager.IMPORTANCE_LOW
+            ).apply {
+                description = "Keep app running in background"
+                setShowBadge(false)
+            }
+            
+            val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+            notificationManager.createNotificationChannel(channel)
+        }
+    }
+    
+    private fun createNotification(): Notification {
+        val intent = Intent(this, MainActivity::class.java)
+        val pendingIntent = PendingIntent.getActivity(
+            this,
+            0,
+            intent,
+            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
+        )
+        
+        return NotificationCompat.Builder(this, CHANNEL_ID)
+            .setContentTitle("LBJ Console")
+            .setContentText("Running in background")
+            .setSmallIcon(R.drawable.ic_launcher_foreground)
+            .setContentIntent(pendingIntent)
+            .setOngoing(true)
+            .setPriority(NotificationCompat.PRIORITY_LOW)
+            .build()
+    }
+    
+    private fun acquireWakeLock() {
+        val powerManager = getSystemService(Context.POWER_SERVICE) as PowerManager
+        wakeLock = powerManager.newWakeLock(
+            PowerManager.PARTIAL_WAKE_LOCK,
+            "LBJConsole::BackgroundWakeLock"
+        )
+        wakeLock?.acquire()
+    }
+    
+    private fun releaseWakeLock() {
+        wakeLock?.let {
+            if (it.isHeld) {
+                it.release()
+            }
+        }
+        wakeLock = null
+    }
+}

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

@@ -47,6 +47,7 @@ import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.window.Dialog
 import androidx.compose.ui.window.DialogProperties
+import androidx.compose.ui.platform.LocalContext
 import androidx.core.content.ContextCompat
 import androidx.core.content.FileProvider
 import kotlinx.coroutines.delay
@@ -61,7 +62,7 @@ import org.noxylva.lbjconsole.ui.screens.HistoryScreen
 import org.noxylva.lbjconsole.ui.screens.MapScreen
 import org.noxylva.lbjconsole.ui.screens.SettingsScreen
 
-import org.noxylva.lbjconsole.ui.theme.LBJReceiverTheme
+import org.noxylva.lbjconsole.ui.theme.LBJConsoleTheme
 import org.noxylva.lbjconsole.util.LocoInfoUtil
 import java.util.*
 import androidx.lifecycle.lifecycleScope
@@ -256,7 +257,7 @@ class MainActivity : ComponentActivity() {
                 tileDownloadThreads = 4
                 tileFileSystemThreads = 4
                 
-                setUserAgentValue("LBJReceiver/1.0")
+                setUserAgentValue("LBJConsole/1.0")
             }
             
             Log.d(TAG, "OSM cache configured")
@@ -266,13 +267,17 @@ class MainActivity : ComponentActivity() {
         
         saveSettings()
         
+        if (SettingsActivity.isBackgroundServiceEnabled(this)) {
+            BackgroundService.startService(this)
+        }
+        
         enableEdgeToEdge()
         
         WindowCompat.getInsetsController(window, window.decorView).apply {
             isAppearanceLightStatusBars = false
         }
         setContent {
-            LBJReceiverTheme {
+            LBJConsoleTheme {
                 val scope = rememberCoroutineScope()
                 
                 Surface(modifier = Modifier.fillMaxSize()) {
@@ -406,7 +411,11 @@ class MainActivity : ComponentActivity() {
                             Log.d(TAG, "Applied settings deviceName=${settingsDeviceName}")
                         },
                         appVersion = getAppVersion(),
-                        locoInfoUtil = locoInfoUtil
+                        locoInfoUtil = locoInfoUtil,
+                        onOpenSettings = {
+                            val intent = Intent(this@MainActivity, SettingsActivity::class.java)
+                            startActivity(intent)
+                        }
                     )
                     
                     if (showConnectionDialog) {
@@ -879,7 +888,9 @@ fun MainContent(
     mapCenterPosition: Pair<Double, Double>?,
     mapZoomLevel: Double,
     mapRailwayLayerVisible: Boolean,
-    onMapStateChange: (Pair<Double, Double>?, Double, Boolean) -> Unit
+    onMapStateChange: (Pair<Double, Double>?, Double, Boolean) -> Unit,
+    
+    onOpenSettings: () -> Unit
 ) {
     val statusColor = if (isConnected) Color(0xFF4CAF50) else Color(0xFFFF5722)
     

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

@@ -0,0 +1,63 @@
+package org.noxylva.lbjconsole
+
+import android.content.Context
+import android.content.SharedPreferences
+import android.os.Bundle
+import android.widget.Switch
+import androidx.appcompat.app.AppCompatActivity
+
+class SettingsActivity : AppCompatActivity() {
+    
+    companion object {
+        private const val PREFS_NAME = "lbj_console_settings"
+        private const val KEY_BACKGROUND_SERVICE = "background_service_enabled"
+        
+        fun isBackgroundServiceEnabled(context: Context): Boolean {
+            val prefs = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+            return prefs.getBoolean(KEY_BACKGROUND_SERVICE, false)
+        }
+        
+        fun setBackgroundServiceEnabled(context: Context, enabled: Boolean) {
+            val prefs = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+            prefs.edit().putBoolean(KEY_BACKGROUND_SERVICE, enabled).apply()
+        }
+    }
+    
+    private lateinit var backgroundServiceSwitch: Switch
+    private lateinit var prefs: SharedPreferences
+    
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_settings)
+        
+        supportActionBar?.setDisplayHomeAsUpEnabled(true)
+        supportActionBar?.title = "Settings"
+        
+        prefs = getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+        
+        initViews()
+        setupListeners()
+    }
+    
+    private fun initViews() {
+        backgroundServiceSwitch = findViewById(R.id.switch_background_service)
+        backgroundServiceSwitch.isChecked = isBackgroundServiceEnabled(this)
+    }
+    
+    private fun setupListeners() {
+        backgroundServiceSwitch.setOnCheckedChangeListener { _, isChecked ->
+            setBackgroundServiceEnabled(this, isChecked)
+            
+            if (isChecked) {
+                BackgroundService.startService(this)
+            } else {
+                BackgroundService.stopService(this)
+            }
+        }
+    }
+    
+    override fun onSupportNavigateUp(): Boolean {
+        onBackPressed()
+        return true
+    }
+}

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

@@ -10,6 +10,7 @@ import androidx.compose.runtime.*
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
+import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalUriHandler
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
@@ -17,6 +18,8 @@ import androidx.compose.ui.unit.dp
 import org.noxylva.lbjconsole.model.MergeSettings
 import org.noxylva.lbjconsole.model.GroupBy
 import org.noxylva.lbjconsole.model.TimeWindow
+import org.noxylva.lbjconsole.SettingsActivity
+import org.noxylva.lbjconsole.BackgroundService
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.runtime.LaunchedEffect
@@ -164,6 +167,72 @@ fun SettingsScreen(
             }
         }
         
+        Card(
+            modifier = Modifier.fillMaxWidth(),
+            colors = CardDefaults.cardColors(
+                containerColor = MaterialTheme.colorScheme.surfaceVariant.copy(alpha = 0.3f)
+            ),
+            shape = RoundedCornerShape(16.dp)
+        ) {
+            Column(
+                modifier = Modifier.padding(20.dp),
+                verticalArrangement = Arrangement.spacedBy(16.dp)
+            ) {
+                Row(
+                    verticalAlignment = Alignment.CenterVertically,
+                    horizontalArrangement = Arrangement.spacedBy(12.dp)
+                ) {
+                    Icon(
+                        imageVector = Icons.Default.Settings,
+                        contentDescription = null,
+                        tint = MaterialTheme.colorScheme.primary
+                    )
+                    Text(
+                        "应用设置",
+                        style = MaterialTheme.typography.titleMedium,
+                        fontWeight = FontWeight.SemiBold
+                    )
+                }
+                
+                val context = LocalContext.current
+                var backgroundServiceEnabled by remember {
+                    mutableStateOf(SettingsActivity.isBackgroundServiceEnabled(context))
+                }
+                
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.SpaceBetween,
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Column {
+                        Text(
+                            "后台保活服务",
+                            style = MaterialTheme.typography.bodyMedium,
+                            fontWeight = FontWeight.Medium
+                        )
+                        Text(
+                            "保持应用在后台运行",
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant
+                        )
+                    }
+                    Switch(
+                        checked = backgroundServiceEnabled,
+                        onCheckedChange = { enabled ->
+                            backgroundServiceEnabled = enabled
+                            SettingsActivity.setBackgroundServiceEnabled(context, enabled)
+                            
+                            if (enabled) {
+                                BackgroundService.startService(context)
+                            } else {
+                                BackgroundService.stopService(context)
+                            }
+                        }
+                    )
+                }
+            }
+        }
+        
         Card(
             modifier = Modifier.fillMaxWidth(),
             colors = CardDefaults.cardColors(

app/src/main/java/org/noxylva/lbjconsole/ui/theme/Theme.kt

@@ -24,7 +24,7 @@ private val LightColorScheme = lightColorScheme(
 )
 
 @Composable
-fun LBJReceiverTheme(
+fun LBJConsoleTheme(
     darkTheme: Boolean = true, 
     
     dynamicColor: Boolean = true,

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

@@ -0,0 +1,55 @@
+<?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="match_parent"
+    android:orientation="vertical"
+    android:padding="16dp">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:orientation="horizontal"
+        android:gravity="center_vertical"
+        android:padding="16dp"
+        android:background="?android:attr/selectableItemBackground"
+        android:clickable="true">
+
+        <LinearLayout
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:orientation="vertical">
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="Background Service"
+                android:textSize="16sp"
+                android:textColor="@android:color/black"
+                android:textStyle="bold" />
+
+            <TextView
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="Keep app running in background"
+                android:textSize="14sp"
+                android:textColor="@android:color/darker_gray"
+                android:layout_marginTop="4dp" />
+
+        </LinearLayout>
+
+        <Switch
+            android:id="@+id/switch_background_service"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_marginStart="16dp" />
+
+    </LinearLayout>
+
+    <View
+        android:layout_width="match_parent"
+        android:layout_height="1dp"
+        android:background="@android:color/darker_gray"
+        android:layout_marginHorizontal="16dp" />
+
+</LinearLayout>

app/src/main/res/values/themes.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 
-    <style name="Theme.LBJReceiver" parent="android:Theme.Material.Light.NoActionBar" />
+    <style name="Theme.LBJConsole" parent="android:Theme.Material.Light.NoActionBar" />
 </resources>