3

lib/views/home/index/widgets/monitoring_screen.dart

 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_screenutil/flutter_screenutil.dart';
+import 'package:laki_icu_app/services/usb_camera_service.dart';
 
 import 'camera_controls.dart';
 
@@ -9,6 +10,7 @@ import 'camera_controls.dart';
 /// 职责：
 /// - 通过 AndroidView 嵌入 Android 原生 USBCameraTextureView 预览画面
 /// - 底部控制栏：拍照、录像、刷新按钮
+/// - 通过 [UsbCameraService] 与原生层通信
 ///
 /// 涉及页面：首页监护舱页面
 class MonitoringScreen extends StatefulWidget {
@@ -32,6 +34,13 @@ class _MonitoringScreenState extends State<MonitoringScreen> {
   bool _cameraReady = false;
 
   @override
+  void dispose() {
+    // 退出页面时关闭摄像头
+    UsbCameraService.closeCamera();
+    super.dispose();
+  }
+
+  @override
   Widget build(BuildContext context) {
     return Container(
       decoration: BoxDecoration(
@@ -67,32 +76,20 @@ class _MonitoringScreenState extends State<MonitoringScreen> {
 
   /// 构建 USB 摄像头预览画面（通过 PlatformView）
   Widget _buildCameraPreview() {
-    // AndroidView 需要 Android API 20+，且仅在 Android 平台有效
-    // 在其他平台或未连接 USB 摄像头时显示占位符
-    try {
-      return ClipRRect(
-        borderRadius: BorderRadius.circular(20.r),
-        child: SizedBox.expand(
-          child: _buildAndroidView(),
+    return ClipRRect(
+      borderRadius: BorderRadius.circular(20.r),
+      child: SizedBox.expand(
+        child: AndroidView(
+          viewType: 'usb_camera_view',
+          onPlatformViewCreated: (_) {
+            setState(() {
+              _cameraReady = true;
+            });
+          },
+          creationParams: const <String, dynamic>{},
+          creationParamsCodec: const StandardMessageCodec(),
         ),
-      );
-    } catch (_) {
-      return const SizedBox.shrink();
-    }
-  }
-
-  /// 构建 Android 原生 PlatformView
-  Widget _buildAndroidView() {
-    // ignore: undefined_platform_specific_widget
-    return AndroidView(
-      viewType: 'usb_camera_view',
-      onPlatformViewCreated: (_) {
-        setState(() {
-          _cameraReady = true;
-        });
-      },
-      creationParams: const <String, dynamic>{},
-      creationParamsCodec: const StandardMessageCodec(),
+      ),
     );
   }
 
@@ -131,30 +128,23 @@ class _MonitoringScreenState extends State<MonitoringScreen> {
 
   /// 拍照
   Future<void> _onTakePhoto() async {
-    // 调用 Service 层拍照
-    final cameraService = await _getCameraService();
-    if (cameraService != null) {
-      final path = await cameraService.takePhoto();
-      if (path != null && mounted) {
-        _showSnackBar('拍照成功: $path');
-      }
+    final path = await UsbCameraService.takePhoto();
+    if (path != null && mounted) {
+      _showSnackBar('拍照成功: $path');
     }
     widget.onSnapshot?.call();
   }
 
   /// 切换录像状态
   Future<void> _onToggleRecord() async {
-    final cameraService = await _getCameraService();
-    if (cameraService == null) return;
-
     if (_isRecording) {
-      final path = await cameraService.stopRecord();
+      final path = await UsbCameraService.stopRecord();
       if (path != null && mounted) {
         _showSnackBar('录像已保存: $path');
       }
       setState(() => _isRecording = false);
     } else {
-      final success = await cameraService.startRecord();
+      final success = await UsbCameraService.startRecord();
       if (success) {
         setState(() => _isRecording = true);
         if (mounted) _showSnackBar('开始录像');
@@ -163,18 +153,6 @@ class _MonitoringScreenState extends State<MonitoringScreen> {
     widget.onRecord?.call();
   }
 
-  /// 获取摄像头服务实例
-  Future<dynamic> _getCameraService() async {
-    // 延迟导入，避免在非 Android 平台导入时出现问题
-    try {
-      // 动态调用 UsbCameraService
-      // ignore: depend_on_referenced_packages
-      return _UsbCameraServiceProxy();
-    } catch (_) {
-      return null;
-    }
-  }
-
   void _showSnackBar(String message) {
     ScaffoldMessenger.of(context).showSnackBar(
       SnackBar(
@@ -189,41 +167,3 @@ class _MonitoringScreenState extends State<MonitoringScreen> {
     );
   }
 }
-
-/// USB 摄像头服务代理 —— 避免硬依赖导致非 Android 平台编译错误
-class _UsbCameraServiceProxy {
-  Future<String?> takePhoto({String? path}) async {
-    // 通过 MethodChannel 直接调用（与 UsbCameraService 使用同一个 channel）
-    const channel = MethodChannel('usb_camera');
-    try {
-      final result = await channel.invokeMethod('takePhoto', {
-        if (path != null) 'path': path,
-      });
-      return result as String?;
-    } catch (_) {
-      return null;
-    }
-  }
-
-  Future<bool> startRecord({String? path}) async {
-    const channel = MethodChannel('usb_camera');
-    try {
-      final result = await channel.invokeMethod('startRecord', {
-        if (path != null) 'path': path,
-      });
-      return result == true;
-    } catch (_) {
-      return false;
-    }
-  }
-
-  Future<String?> stopRecord() async {
-    const channel = MethodChannel('usb_camera');
-    try {
-      final result = await channel.invokeMethod('stopRecord');
-      return result as String?;
-    } catch (_) {
-      return null;
-    }
-  }
-}