fix: 自动申请权限 + 图标消失 + 授权后自动切换

权限流程:
- 启动时自动弹出系统授权对话框（不再需要用户手动点击）
- 通过 SideEffect 桥接 Compose state，授权后自动切换到主界面
- 授权等待中显示加载指示器

图标修复:
- 合并两个 intent-filter 为一个（LAUNCHER + LEANBACK_LAUNCHER）
- 移除 singleTask launchMode 避免启动器图标异常

MainActivity 简化:
- 移除 recreate() 循环触发
- 移除多余的回调闭包

app/src/main/AndroidManifest.xml

@@ -47,16 +47,12 @@
             android:name=".ui.MainActivity"
             android:exported="true"
             android:configChanges="orientation|screenSize|screenLayout|keyboardHidden"
-            android:banner="@drawable/tv_banner"
-            android:launchMode="singleTask">
+            android:banner="@drawable/tv_banner">
 
-            <intent-filter>
-                <action android:name="android.intent.action.MAIN" />
-                <category android:name="android.intent.category.LEANBACK_LAUNCHER" />
-            </intent-filter>
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
+                <category android:name="android.intent.category.LEANBACK_LAUNCHER" />
             </intent-filter>
         </activity>
 

app/src/main/java/com/qwenpaw/miracast/ui/MainActivity.kt

@@ -8,7 +8,6 @@ import android.content.pm.PackageManager
 import android.os.Build
 import android.os.Bundle
 import android.os.IBinder
-import android.util.Log
 import android.view.SurfaceView
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
@@ -30,50 +29,41 @@ import com.qwenpaw.miracast.ui.theme.*
 
 class MainActivity : ComponentActivity() {
 
-    companion object {
-        private const val TAG = "MainActivity"
-    }
-
     private var service: AirDisplayService? = null
     private var serviceBound = false
+    private var surfaceView: SurfaceView? = null
+
+    // Compose state 引用，供 Activity 层写入
+    private var onPermissionGranted: (() -> Unit)? = null
 
     private val serviceConnection = object : ServiceConnection {
         override fun onServiceConnected(name: ComponentName?, binder: IBinder?) {
             service = (binder as AirDisplayService.LocalBinder).getService()
             serviceBound = true
             surfaceView?.let { service?.setSurface(it) }
-            Log.i(TAG, "服务已绑定")
         }
         override fun onServiceDisconnected(name: ComponentName?) {
-            serviceBound = false
-            service = null
+            serviceBound = false; service = null
         }
     }
 
-    private var surfaceView: SurfaceView? = null
-
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        val hasPerm = checkPermissions()
+        val alreadyGranted = checkPermissions()
 
         setContent {
-            var permGranted by remember { mutableStateOf(hasPerm) }
+            var permGranted by remember { mutableStateOf(alreadyGranted) }
             var serviceStarted by remember { mutableStateOf(false) }
 
-            val darkColors = darkColorScheme(
-                primary = Primary,
-                onPrimary = OnPrimary,
-                secondary = Secondary,
-                background = Background,
-                surface = Surface,
-                surfaceVariant = SurfaceVariant,
-                onSurface = OnSurface,
-                onSurfaceVariant = OnSurfaceVariant,
-                error = Error
-            )
+            // 暴露 setter 给 Activity 层
+            SideEffect { onPermissionGranted = { permGranted = true } }
 
-            MaterialTheme(colorScheme = darkColors) {
+            MaterialTheme(colorScheme = darkColorScheme(
+                primary = Primary, onPrimary = OnPrimary, secondary = Secondary,
+                background = Background, surface = Surface, surfaceVariant = SurfaceVariant,
+                onSurface = OnSurface, onSurfaceVariant = OnSurfaceVariant, error = Error
+            )) {
                 Box(modifier = Modifier.fillMaxSize()) {
                     AndroidView(
                         factory = { ctx -> SurfaceView(ctx).also { surfaceView = it } },
@@ -83,36 +73,29 @@ class MainActivity : ComponentActivity() {
                     if (permGranted) {
                         AppContent(
                             serviceStarted = serviceStarted,
-                            onServiceStarted = {
-                                bindToService()
-                                startService()
-                                serviceStarted = true
-                            }
+                            onStart = { bindAndStart(); serviceStarted = true }
                         )
                     } else {
-                        PermissionScreen(
-                            onRequestPermissions = {
-                                requestPermission { permGranted = true }
-                            }
-                        )
+                        PermissionScreen()
                     }
                 }
             }
         }
+
+        // 首次启动自动弹出系统授权框
+        if (!alreadyGranted) {
+            permLauncher.launch(getRequiredPermission())
+        }
     }
 
     @Composable
-    private fun AppContent(serviceStarted: Boolean, onServiceStarted: () -> Unit) {
-        LaunchedEffect(Unit) {
-            if (!serviceStarted) {
-                onServiceStarted()
-            }
-        }
+    private fun AppContent(serviceStarted: Boolean, onStart: () -> Unit) {
+        LaunchedEffect(Unit) { if (!serviceStarted) onStart() }
 
         var currentScreen by remember { mutableStateOf("main") }
-        val defaultState = AirDisplayManager.UiState()
-        val state by service?.manager?.uiState?.collectAsStateWithLifecycle(defaultState)
-            ?: remember { mutableStateOf(defaultState) }
+        val def = AirDisplayManager.UiState()
+        val state by service?.manager?.uiState?.collectAsStateWithLifecycle(def)
+            ?: remember { mutableStateOf(def) }
 
         when (currentScreen) {
             "settings" -> {
@@ -125,11 +108,8 @@ class MainActivity : ComponentActivity() {
             else -> MainScreen(
                 uiState = state,
                 onStartStop = {
-                    if (state.serviceState is AirDisplayManager.ServiceState.Idle) {
-                        startService()
-                    } else {
-                        stopService()
-                    }
+                    if (state.serviceState is AirDisplayManager.ServiceState.Idle) startSvc()
+                    else stopSvc()
                 },
                 onNavigateToSettings = { currentScreen = "settings" }
             )
@@ -138,96 +118,65 @@ class MainActivity : ComponentActivity() {
 
     // ── 权限 ──
 
-    private fun checkPermissions(): Boolean {
-        val perm = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+    private fun getRequiredPermission() =
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU)
             Manifest.permission.NEARBY_WIFI_DEVICES
-        } else {
+        else
             Manifest.permission.ACCESS_FINE_LOCATION
-        }
-        return ContextCompat.checkSelfPermission(this, perm) == PackageManager.PERMISSION_GRANTED
-    }
 
-    private fun requestPermission(onGranted: () -> Unit) {
-        val perm = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
-            Manifest.permission.NEARBY_WIFI_DEVICES
-        } else {
-            Manifest.permission.ACCESS_FINE_LOCATION
-        }
-        permLauncher.launch(perm)
-        // 存储回调，等下在 launcher 结果里调用
-        pendingOnGranted = onGranted
-    }
-
-    private var pendingOnGranted: (() -> Unit)? = null
+    private fun checkPermissions() =
+        ContextCompat.checkSelfPermission(this, getRequiredPermission()) == PackageManager.PERMISSION_GRANTED
 
     private val permLauncher = registerForActivityResult(
         ActivityResultContracts.RequestPermission()
     ) { granted ->
         if (granted || Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
-            pendingOnGranted?.invoke()
+            onPermissionGranted?.invoke()
         }
     }
 
     // ── 服务 ──
 
-    private fun bindToService() {
-        val intent = Intent(this, AirDisplayService::class.java)
-        bindService(intent, serviceConnection, BIND_AUTO_CREATE)
+    private fun bindAndStart() {
+        bindService(Intent(this, AirDisplayService::class.java), serviceConnection, BIND_AUTO_CREATE)
+        startSvc()
     }
 
-    private fun startService() {
-        val intent = Intent(this, AirDisplayService::class.java).apply {
-            action = AirDisplayService.ACTION_START
-        }
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
-            startForegroundService(intent)
-        } else {
-            startService(intent)
-        }
+    private fun startSvc() {
+        val i = Intent(this, AirDisplayService::class.java).apply { action = AirDisplayService.ACTION_START }
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) startForegroundService(i) else startService(i)
     }
 
-    private fun stopService() {
-        val intent = Intent(this, AirDisplayService::class.java).apply {
-            action = AirDisplayService.ACTION_STOP
-        }
-        startService(intent)
+    private fun stopSvc() {
+        startService(Intent(this, AirDisplayService::class.java).apply { action = AirDisplayService.ACTION_STOP })
     }
 
     override fun onDestroy() {
-        if (serviceBound) {
-            unbindService(serviceConnection)
-            serviceBound = false
-        }
+        if (serviceBound) { unbindService(serviceConnection); serviceBound = false }
         super.onDestroy()
     }
 }
 
-// ── 权限界面 ──
+// ── 权限提示 ──
 
 @Composable
-private fun PermissionScreen(onRequestPermissions: () -> Unit) {
-    Box(modifier = Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+private fun PermissionScreen() {
+    Box(modifier = Modifier.fillMaxSize().padding(32.dp), contentAlignment = Alignment.Center) {
         Card(colors = CardDefaults.cardColors(containerColor = Surface)) {
             Column(
                 modifier = Modifier.padding(32.dp),
                 horizontalAlignment = Alignment.CenterHorizontally
             ) {
-                Text(
-                    "需要 Wi-Fi Direct 权限",
-                    fontSize = 20.sp,
-                    fontWeight = FontWeight.Bold,
-                    color = OnSurface
-                )
+                Text("需要授权", fontSize = 20.sp, fontWeight = FontWeight.Bold, color = OnSurface)
                 Spacer(Modifier.height(12.dp))
                 Text(
-                    "AirDisplay 需要邻近设备/位置权限才能进行 Wi-Fi Direct 无线投屏。",
-                    color = OnSurfaceVariant,
-                    fontSize = 14.sp
+                    "系统已弹出授权对话框，请选择「允许」以启用 Wi-Fi Direct 投屏功能。",
+                    color = OnSurfaceVariant, fontSize = 14.sp
                 )
-                Spacer(Modifier.height(24.dp))
-                Button(onClick = onRequestPermissions) {
-                    Text("授予权限")
-                }
+                Spacer(Modifier.height(16.dp))
+                CircularProgressIndicator(modifier = Modifier.size(24.dp), strokeWidth = 2.dp)
+                Spacer(Modifier.height(8.dp))
+                Text("等待授权…", color = OnSurfaceVariant, fontSize = 12.sp)
             }
         }
     }