1

flutter_app/lib/camera/camera_screen.dart

@@ -47,6 +47,79 @@ class _CameraScreenState extends State<CameraScreen> {
   /// ModelManager revision 快照：模型文件更新（自动更新下载新版）也需重建 worker
   int _lastRevision = -1;
 
+  /// C 端状态胶囊：3 秒内连点 5 次切换完整开发诊断（远程收截图报障仍可取数）
+  bool _devInfo = false;
+  final List<DateTime> _devTaps = [];
+
+  /// 推理 worker 后台重建中（启用/停用模型触发）：期间 modelReady 仍为 false，
+  /// 胶囊与顶部横幅显示「识别准备中」，不误报「模型加载失败」
+  bool _workerPending = false;
+
+  void _onDevTaps() {
+    final now = DateTime.now();
+    _devTaps.add(now);
+    _devTaps
+        .removeWhere((t) => now.difference(t) > const Duration(seconds: 3));
+    if (_devTaps.length < 5) return;
+    _devTaps.clear();
+    setState(() => _devInfo = !_devInfo);
+  }
+
+  /// 识别延迟分档（C 端直观读法：流畅 / 一般 / 偏慢）
+  ({String label, Color color}) _latencyBucket(double avgMs) {
+    if (avgMs <= 200) return (label: '流畅', color: Colors.greenAccent);
+    if (avgMs <= 600) return (label: '一般', color: Colors.amberAccent);
+    return (label: '偏慢', color: Colors.redAccent);
+  }
+
+  /// C 端底部状态胶囊内容：设备识别延迟（近帧滚动平均）+ 当前识别模型
+  List<Widget> _statusCapsuleLines(CameraUiState s) {
+    if (!s.modelReady) {
+      if (_workerPending) {
+        // worker 后台构建中（用户刚启用模型）：给个进行时状态，别误读为未启用
+        return const [
+          Text(
+            '识别准备中…',
+            style: TextStyle(color: Colors.white70, fontSize: 13),
+          ),
+        ];
+      }
+      return const [
+        Text(
+          '仅预览 · 未启用识别',
+          style: TextStyle(color: Colors.orangeAccent, fontSize: 12),
+        ),
+      ];
+    }
+    final avg = s.latencyAvgMs;
+    final lines = <Widget>[];
+    if (avg == null) {
+      lines.add(const Text(
+        '识别延迟 --',
+        style: TextStyle(color: Colors.white54, fontSize: 13),
+      ));
+    } else {
+      final b = _latencyBucket(avg);
+      lines.add(Text(
+        '识别延迟 ${(avg / 1000).toStringAsFixed(2)} 秒 · ${b.label}',
+        style: TextStyle(
+          color: b.color,
+          fontSize: 13,
+          fontWeight: FontWeight.w600,
+        ),
+      ));
+    }
+    final names = ModelManager.instance.modelsLabel;
+    if (names.isNotEmpty && names != '未下载') {
+      lines.add(Text(
+        '识别模型：$names',
+        textAlign: TextAlign.center,
+        style: const TextStyle(color: Colors.white54, fontSize: 10.5),
+      ));
+    }
+    return lines;
+  }
+
   void _openSettings() {
     final vm = _viewModel;
     if (vm == null) return;
@@ -56,53 +129,66 @@ class _CameraScreenState extends State<CameraScreen> {
       isScrollControlled: true,
       backgroundColor: Colors.black87,
       builder: (ctx) => StatefulBuilder(
-        builder: (ctx, setSheetState) => SingleChildScrollView(
-          child: Padding(
-            padding: const EdgeInsets.all(20),
-            child: Column(
-              mainAxisSize: MainAxisSize.min,
-              crossAxisAlignment: CrossAxisAlignment.start,
-              children: [
-                const Text('识别设置',
+        // 弹层高度 ≤ 70% 屏高：超过会盖满全屏使遮罩无处点按，弹层无法关闭
+        builder: (ctx, setSheetState) => ConstrainedBox(
+          constraints: BoxConstraints(
+            maxHeight: MediaQuery.of(ctx).size.height * 0.7,
+          ),
+          child: SingleChildScrollView(
+            child: Padding(
+              padding: const EdgeInsets.all(20),
+              child: Column(
+                mainAxisSize: MainAxisSize.min,
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  const Text(
+                    '识别设置',
                     style: TextStyle(
-                        color: Colors.white,
-                        fontSize: 16,
-                        fontWeight: FontWeight.bold)),
-                const SizedBox(height: 12),
-                Row(
-                  children: [
-                    const Text('置信度阈值',
-                        style:
-                            TextStyle(color: Colors.white70, fontSize: 14)),
-                    const Spacer(),
-                    Text('${(_minScore * 100).toStringAsFixed(0)}%',
+                      color: Colors.white,
+                      fontSize: 16,
+                      fontWeight: FontWeight.bold,
+                    ),
+                  ),
+                  const SizedBox(height: 12),
+                  Row(
+                    children: [
+                      const Text(
+                        '置信度阈值',
+                        style: TextStyle(color: Colors.white70, fontSize: 14),
+                      ),
+                      const Spacer(),
+                      Text(
+                        '${(_minScore * 100).toStringAsFixed(0)}%',
                         style: const TextStyle(
-                            color: Colors.greenAccent,
-                            fontSize: 14,
-                            fontWeight: FontWeight.bold)),
-                  ],
-                ),
-                Slider(
-                  value: _minScore,
-                  min: 0.05,
-                  max: 0.50,
-                  divisions: 45,
-                  activeColor: Colors.greenAccent,
-                  onChanged: (v) {
-                    setSheetState(() => _minScore = v);
-                    _analyzer?.worker?.setMinScore(v);
-                  },
-                ),
-                const SizedBox(height: 8),
-                const Text(
-                  '阈值越低识别越灵敏（低分框越多，误报也可能增加）',
-                  style: TextStyle(color: Colors.white54, fontSize: 12),
-                ),
-                const SizedBox(height: 16),
-                const Divider(color: Colors.white12),
-                const SizedBox(height: 8),
-                ModelCatalogSection(manager: ModelManager.instance),
-              ],
+                          color: Colors.greenAccent,
+                          fontSize: 14,
+                          fontWeight: FontWeight.bold,
+                        ),
+                      ),
+                    ],
+                  ),
+                  Slider(
+                    value: _minScore,
+                    min: 0.05,
+                    max: 0.50,
+                    divisions: 45,
+                    activeColor: Colors.greenAccent,
+                    onChanged: (v) {
+                      setSheetState(() => _minScore = v);
+                      _analyzer?.worker?.setMinScore(v);
+                    },
+                  ),
+                  const SizedBox(height: 8),
+                  const Text(
+                    '阈值越低识别越灵敏（低分框越多，误报也可能增加）',
+                    style: TextStyle(color: Colors.white54, fontSize: 12),
+                  ),
+                  const SizedBox(height: 16),
+                  const Divider(color: Colors.white12),
+                  const SizedBox(height: 8),
+                  ModelCatalogSection(manager: ModelManager.instance),
+                ],
+              ),
             ),
           ),
         ),
@@ -115,15 +201,20 @@ class _CameraScreenState extends State<CameraScreen> {
     super.initState();
     final oldPlatform = ui.PlatformDispatcher.instance.onError;
     ui.PlatformDispatcher.instance.onError = (error, stack) {
-      setState(() => _globalError =
-          'Platform: $error\n${stack.toString().split('\n').take(3).join('\n')}');
+      setState(
+        () => _globalError =
+            'Platform: $error\n${stack.toString().split('\n').take(3).join('\n')}',
+      );
       return oldPlatform?.call(error, stack) ?? false;
     };
     WidgetsBinding.instance.addPostFrameCallback((_) => _init());
     // 相机页常亮：野外观察时保持屏幕不熄（离开页面时关闭）
     WakelockPlus.enable();
     // 每秒轮询原生侧帧状态：无帧时诊断行也能实时刷新（camErr/计数）
-    _statsTimer = Timer.periodic(const Duration(seconds: 1), (_) => _pollStats());
+    _statsTimer = Timer.periodic(
+      const Duration(seconds: 1),
+      (_) => _pollStats(),
+    );
     // 模型清单激活集变化（下载完成自动激活/取消激活）时重建推理 worker
     ModelManager.instance.addListener(_onModelsChanged);
   }
@@ -142,29 +233,37 @@ class _CameraScreenState extends State<CameraScreen> {
     setState(() => _permissionGranted = granted);
     if (!granted) return;
 
-    // 模型热更新：启动拉取目录（只拉不下载），兜底等待；已下载/已激活模型
-    // 有新版本时 autoUpdate 自动重下，变化经 _onModelsChanged 重建 worker
-    try {
-      await ModelManager.instance
-          .refresh()
-          .timeout(const Duration(seconds: 30));
-    } catch (_) {}
-    await _reloadWorker();
+    // 新识别会话（2026-09-03）：不恢复上次启用的模型——每次进入都从仅预览开始，
+    // 识别需用户在模型清单手动启用；崩溃/坏模型不会自动复现。激活集变化经
+    // _onModelsChanged 重建 worker 挂载
+    ModelManager.instance.resetForSession();
+    // 目录同步先行（缓存优先，2026-09-03）：进页面立即触发——refresh 开头先把
+    // 上次成功目录从磁盘载入并 notify，设置弹层打开即有内容（不完全依赖网络）；
+    // 网络拉取/自动更新在后台继续，全程不阻塞预览
+    unawaited(ModelManager.instance.refresh());
+    // 先出预览：占位 analyzer（无 worker）让相机立即启动，识别加载完再原地挂上
+    if (_analyzer == null) {
+      final vm = CameraViewModel(reminder: Reminder());
+      _viewModel = vm;
+      _analyzer = FrameAnalyzer(worker: null, viewModel: vm);
+    }
     await _startCamera();
   }
 
-  /// 用当前激活模型重建推理 worker（激活集变化/启动时调用）；
-  /// worker 为 null（无激活模型或加载失败）时仅预览并提示。
-  /// 并发调用共享同一进行中的重建：refresh 通知触发的重建与 _init 的等待
-  /// 共用一个 Future，相机等重建完成后再启动（避免绑定旧 analyzer）。
+  /// 用当前激活模型重建推理 worker（启用/停用模型、模型文件更新时调用）；
+  /// worker 为 null（无启用模型或加载失败）时仅预览并提示。
+  /// 并发调用共享同一进行中的重建：进行中时先等完成再复查，期间变化不丢失。
   Future<void> _reloadWorker() {
     final inFlight = _reloadInFlight;
     if (inFlight != null) {
       // 重建进行中：完成后按最新状态复查，期间的变化不丢失
       return inFlight.then((_) => _reloadWorker()).catchError((_) {});
     }
-    _reloadInFlight =
-        _doReloadWorker().whenComplete(() => _reloadInFlight = null);
+    if (mounted) setState(() => _workerPending = true);
+    _reloadInFlight = _doReloadWorker().whenComplete(() {
+      _reloadInFlight = null;
+      if (mounted) setState(() => _workerPending = false);
+    });
     return _reloadInFlight!;
   }
 
@@ -182,24 +281,31 @@ class _CameraScreenState extends State<CameraScreen> {
     _lastRevision = mgr.revision;
     final worker = await DetectorWorker.create(models: models);
     _loadedModelIds = ids;
+    if (!mounted) {
+      worker?.dispose();
+      return; // 页面已关闭：不触碰可能已 dispose 的 vm/analyzer
+    }
     final vm = _viewModel ?? CameraViewModel(reminder: Reminder());
     vm.setModelReady(worker != null);
-    final analyzer = FrameAnalyzer(worker: worker, viewModel: vm);
-    final old = _analyzer;
-    if (!mounted) {
-      analyzer.dispose();
-      if (vm != _viewModel) vm.dispose();
+    // 重建后把设置页调过的阈值落到新 worker（避免静默回到默认值）
+    worker?.setMinScore(_minScore);
+    final existing = _analyzer;
+    if (existing == null) {
+      // 相机尚未绑定 analyzer（冷启动竞态兜底）：直接以新 worker 建 analyzer
+      final analyzer = FrameAnalyzer(worker: worker, viewModel: vm);
+      setState(() {
+        _viewModel = vm;
+        _analyzer = analyzer;
+      });
+      if (_cameraController != null) {
+        await _cameraController!.start(analyzer);
+      }
       return;
     }
-    setState(() {
-      _viewModel = vm;
-      _analyzer = analyzer;
-    });
-    old?.worker?.dispose();
-    // 相机已启动：重启帧流绑定新 analyzer（start 内部先 stop 再订阅）
-    if (mounted && _cameraController != null) {
-      await _cameraController!.start(analyzer);
-    }
+    // 相机已绑定（预览中）：worker 原地挂到既有 analyzer——帧流回调闭包捕获的
+    // 是 analyzer 对象本身，替换其 worker 双平台即时生效；重启相机会重新
+    // initialize（iOS ~1s+）且预览闪断，一律避免（2026-09-03）
+    existing.attachWorker(worker);
   }
 
   void _onModelsChanged() {
@@ -310,7 +416,10 @@ class _CameraScreenState extends State<CameraScreen> {
                 child: Column(
                   mainAxisSize: MainAxisSize.min,
                   children: [
-                    const Text('相机初始化失败', style: TextStyle(color: Colors.white)),
+                    const Text(
+                      '相机初始化失败',
+                      style: TextStyle(color: Colors.white),
+                    ),
                     if (_initError != null)
                       Padding(
                         padding: const EdgeInsets.only(top: 8),
@@ -320,7 +429,9 @@ class _CameraScreenState extends State<CameraScreen> {
                           overflow: TextOverflow.ellipsis,
                           textAlign: TextAlign.center,
                           style: const TextStyle(
-                              color: Colors.redAccent, fontSize: 11),
+                            color: Colors.redAccent,
+                            fontSize: 11,
+                          ),
                         ),
                       ),
                     TextButton(
@@ -361,8 +472,7 @@ class _CameraScreenState extends State<CameraScreen> {
             right: 16,
             top: MediaQuery.of(context).padding.top + 56,
             child: Container(
-              padding:
-                  const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
+              padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
               decoration: BoxDecoration(
                 color: Colors.black54,
                 borderRadius: BorderRadius.circular(8),
@@ -375,8 +485,9 @@ class _CameraScreenState extends State<CameraScreen> {
             ),
           ),
 
-        // 模型未加载时仅显示相机预览，不做检测标注（横幅置于顶栏下方，避免与底部诊断行重叠）
-        if (!vm.state.modelReady)
+        // 模型未加载时仅显示相机预览，不做检测标注（横幅置于顶栏下方，避免与底部诊断行重叠）；
+        // worker 后台构建中不提示「加载失败」（modelReady 就绪前的一瞬）
+        if (!vm.state.modelReady && !_workerPending)
           Positioned(
             left: 16,
             right: 16,
@@ -405,56 +516,87 @@ class _CameraScreenState extends State<CameraScreen> {
             mainAxisSize: MainAxisSize.min,
             crossAxisAlignment: CrossAxisAlignment.center,
             children: [
-              Text(
-                '阈值:${(_minScore * 100).toStringAsFixed(0)}% 模型:${vm.state.modelReady ? ModelManager.instance.modelsLabel : '未加载'} 帧:${vm.state.framesReceived} 流:${camera?.streamCallbacks ?? 0} 推理:${vm.state.debugDetectCalls}次 异常:${vm.state.debugDetectErrors}次 处理:${vm.state.debugLastMs}ms 最高分:${(vm.state.debugHighestScore * 100).toStringAsFixed(1)}% 图:${vm.state.imageWidthPx}x${vm.state.imageHeightPx} 传感:${camera?.sensorOrientation ?? '-'} 屏转:${camera?.displayDegrees ?? '-'} 旋:${camera?.rotationDegrees ?? 0} turn:${camera?.quarterTurns ?? '-'}',
-                style: const TextStyle(color: Colors.white70, fontSize: 12),
+              // C 端状态胶囊：识别延迟 + 识别模型（连点 5 次展开完整开发诊断）
+              GestureDetector(
+                behavior: HitTestBehavior.opaque,
+                onTap: _onDevTaps,
+                child: Container(
+                  padding: const EdgeInsets.symmetric(
+                      horizontal: 14, vertical: 6),
+                  decoration: BoxDecoration(
+                    color: Colors.black54,
+                    borderRadius: BorderRadius.circular(16),
+                  ),
+                  child: Column(
+                    mainAxisSize: MainAxisSize.min,
+                    crossAxisAlignment: CrossAxisAlignment.center,
+                    children: _statusCapsuleLines(vm.state),
+                  ),
+                ),
               ),
-              if (_nativeStats.isNotEmpty)
-                Text(
-                  '原生:回调${_nativeStats['callbacks'] ?? '-'} 发出${_nativeStats['emitOk'] ?? '-'} 异常${_nativeStats['emitErr'] ?? '-'} 无订阅${_nativeStats['sinkNull'] ?? '-'} sink:${_nativeStats['sink'] ?? '-'} 配置:${_nativeStats['size'] ?? '-'} 发帧:${_nativeStats['emitSize'] ?? '-'} 错误:${_nativeStats['error'] ?? '无'} 轮询:${_nativeStats['pollErr'] ?? 'ok'}${vm.state.results.isEmpty ? '' : ' 框1:(${vm.state.results.first.left.toStringAsFixed(2)},${vm.state.results.first.top.toStringAsFixed(2)},${vm.state.results.first.right.toStringAsFixed(2)},${vm.state.results.first.bottom.toStringAsFixed(2)})'}',
-                  style: const TextStyle(
-                      color: Colors.amberAccent, fontSize: 11),
+              // —— 开发诊断（默认隐藏，远程排查用）——
+              if (_devInfo) ...[
+                const SizedBox(height: 4),
+                const Text(
+                  '开发诊断（连点上方状态胶囊 5 次收起）',
+                  style: TextStyle(color: Colors.white24, fontSize: 10),
                 ),
-              if (vm.state.debugYuv.isNotEmpty)
                 Text(
-                  'yuv:${vm.state.debugYuv}',
-                  style: const TextStyle(
-                      color: Colors.yellowAccent, fontSize: 11),
-                ),
-              if (camera != null)
-                Text(
-                  'streaming:${camera.isStreaming} '
-                  'camErr:${camera.errorDescription ?? '无'}',
-                  maxLines: 2,
-                  overflow: TextOverflow.ellipsis,
-                  style: const TextStyle(
-                      color: Colors.cyanAccent, fontSize: 11),
-                ),
-              if (vm.state.debugLastError != null)
-                Text(
-                  vm.state.debugLastError!,
-                  maxLines: 2,
-                  overflow: TextOverflow.ellipsis,
-                  textAlign: TextAlign.center,
-                  style: const TextStyle(
-                      color: Colors.redAccent, fontSize: 11),
-                ),
-              if (_globalError != null)
-                Text(
-                  _globalError!,
-                  maxLines: 3,
-                  overflow: TextOverflow.ellipsis,
-                  textAlign: TextAlign.center,
-                  style: const TextStyle(
-                      color: Colors.redAccent, fontSize: 11),
+                  '阈值:${(_minScore * 100).toStringAsFixed(0)}% 模型:${vm.state.modelReady ? ModelManager.instance.modelsLabel : '未加载'} 帧:${vm.state.framesReceived} 流:${camera?.streamCallbacks ?? 0} 推理:${vm.state.debugDetectCalls}次 异常:${vm.state.debugDetectErrors}次 处理:${vm.state.debugLastMs}ms 平均:${vm.state.latencyAvgMs?.toStringAsFixed(0) ?? '-'}ms 最高分:${(vm.state.debugHighestScore * 100).toStringAsFixed(1)}% 图:${vm.state.imageWidthPx}x${vm.state.imageHeightPx} 传感:${camera?.sensorOrientation ?? '-'} 屏转:${camera?.displayDegrees ?? '-'} 旋:${camera?.rotationDegrees ?? 0} turn:${camera?.quarterTurns ?? '-'}',
+                  style: const TextStyle(color: Colors.white70, fontSize: 12),
                 ),
+                if (_nativeStats.isNotEmpty)
+                  Text(
+                    '原生:回调${_nativeStats['callbacks'] ?? '-'} 发出${_nativeStats['emitOk'] ?? '-'} 异常${_nativeStats['emitErr'] ?? '-'} 无订阅${_nativeStats['sinkNull'] ?? '-'} sink:${_nativeStats['sink'] ?? '-'} 配置:${_nativeStats['size'] ?? '-'} 发帧:${_nativeStats['emitSize'] ?? '-'} 错误:${_nativeStats['error'] ?? '无'} 轮询:${_nativeStats['pollErr'] ?? 'ok'}${vm.state.results.isEmpty ? '' : ' 框1:(${vm.state.results.first.left.toStringAsFixed(2)},${vm.state.results.first.top.toStringAsFixed(2)},${vm.state.results.first.right.toStringAsFixed(2)},${vm.state.results.first.bottom.toStringAsFixed(2)})'}',
+                    style: const TextStyle(
+                      color: Colors.amberAccent,
+                      fontSize: 11,
+                    ),
+                  ),
+                if (vm.state.debugYuv.isNotEmpty)
+                  Text(
+                    'yuv:${vm.state.debugYuv}',
+                    style: const TextStyle(
+                      color: Colors.yellowAccent,
+                      fontSize: 11,
+                    ),
+                  ),
+                if (camera != null)
+                  Text(
+                    'streaming:${camera.isStreaming} '
+                    'camErr:${camera.errorDescription ?? '无'}',
+                    maxLines: 2,
+                    overflow: TextOverflow.ellipsis,
+                    style: const TextStyle(
+                      color: Colors.cyanAccent,
+                      fontSize: 11,
+                    ),
+                  ),
+                if (vm.state.debugLastError != null)
+                  Text(
+                    vm.state.debugLastError!,
+                    maxLines: 2,
+                    overflow: TextOverflow.ellipsis,
+                    textAlign: TextAlign.center,
+                    style:
+                        const TextStyle(color: Colors.redAccent, fontSize: 11),
+                  ),
+                if (_globalError != null)
+                  Text(
+                    _globalError!,
+                    maxLines: 3,
+                    overflow: TextOverflow.ellipsis,
+                    textAlign: TextAlign.center,
+                    style:
+                        const TextStyle(color: Colors.redAccent, fontSize: 11),
+                  ),
+              ],
             ],
           ),
         ),
       ],
     );
   }
-
 }
 
 /// 双指捏合缩放预览；overlay 与纹理同几何（Stack 内同尺寸）
@@ -464,10 +606,7 @@ class _ZoomablePreview extends StatefulWidget {
   /// 检测框 overlay（随帧更新，与纹理同区域）
   final Widget? overlay;
 
-  const _ZoomablePreview({
-    required this.controller,
-    this.overlay,
-  });
+  const _ZoomablePreview({required this.controller, this.overlay});
 
   @override
   State<_ZoomablePreview> createState() => _ZoomablePreviewState();
@@ -497,8 +636,7 @@ class _ZoomablePreviewState extends State<_ZoomablePreview> {
     return GestureDetector(
       onScaleStart: (_) => _gestureStartZoom = _currentZoom,
       onScaleUpdate: (d) {
-        final target =
-            (_gestureStartZoom * d.scale).clamp(_minZoom, _maxZoom);
+        final target = (_gestureStartZoom * d.scale).clamp(_minZoom, _maxZoom);
         if ((target - _currentZoom).abs() < 0.01) return;
         _currentZoom = target;
         widget.controller.setZoomLevel(target);
@@ -518,10 +656,7 @@ class _CameraTopBar extends StatelessWidget {
   final VoidCallback onClose;
   final VoidCallback onOpenSettings;
 
-  const _CameraTopBar({
-    required this.onClose,
-    required this.onOpenSettings,
-  });
+  const _CameraTopBar({required this.onClose, required this.onOpenSettings});
 
   @override
   Widget build(BuildContext context) {
@@ -558,10 +693,7 @@ class _PermissionGuide extends StatelessWidget {
       child: Column(
         mainAxisSize: MainAxisSize.min,
         children: [
-          const Text(
-            '需要相机权限才能进行实时识别',
-            style: TextStyle(color: Colors.white),
-          ),
+          const Text('需要相机权限才能进行实时识别', style: TextStyle(color: Colors.white)),
           const SizedBox(height: 16),
           FilledButton(onPressed: onRequest, child: const Text('授权相机')),
         ],

flutter_app/lib/camera/camera_view_model.dart

@@ -4,6 +4,7 @@ import 'package:flutter/foundation.dart';
 
 import '../detection/detection_result.dart';
 import '../detection/motion_aggregator.dart';
+import '../detection/nms.dart';
 import '../reminder/reminder.dart';
 
 @immutable
@@ -21,6 +22,10 @@ class CameraUiState {
   final int debugLastMs;
   final String debugYuv;
 
+  /// 近 [CameraViewModel.latencyWindow] 帧推理耗时滚动平均（毫秒；无样本为 null）。
+  /// 给 C 端用户看的设备识别延迟。
+  final double? latencyAvgMs;
+
   const CameraUiState({
     this.modelReady = false,
     this.results = const [],
@@ -34,6 +39,7 @@ class CameraUiState {
     this.framesReceived = 0,
     this.debugLastMs = 0,
     this.debugYuv = '',
+    this.latencyAvgMs,
   });
 }
 
@@ -43,6 +49,9 @@ class CameraUiState {
 ///   高于 0.35 视为强证据。
 /// - 低于 0.35 的框：需要多帧稳定（[confirmFrames] 帧）或 活动证据
 ///   （运动区域/背景新出现区域重叠）才确认显示。
+/// - 同位置去重（2026-09-03）：多模型对同一目标交替检出时各轨迹都会在
+///   忘记窗内持续显示 → 轨迹层跨标签同目标补挂 + 显示层
+///   [dedupeVisibleOverlaps] 同类别强重叠只保留高置信度框。
 class CameraViewModel extends ChangeNotifier {
   static const int maxTracks = 30;
   static const double motionBoost = 0.15;
@@ -52,6 +61,10 @@ class CameraViewModel extends ChangeNotifier {
   static const int displayAgeMs = 500;
   static const int forgetMs = 2000;
 
+  /// 延迟滚动平均窗口（帧数）：单帧抖动大，取近期均值给用户展示
+  static const int latencyWindow = 30;
+  final List<int> _procWindow = [];
+
   /// 推理后台 isolate 是否就绪（由相机页创建 worker 后设置）
   bool modelReady = false;
 
@@ -68,6 +81,8 @@ class CameraViewModel extends ChangeNotifier {
   void setModelReady(bool ready) {
     if (modelReady == ready) return;
     modelReady = ready;
+    // 换 worker / 停识别：旧窗口样本作废，从零起算
+    _procWindow.clear();
     _state = CameraUiState(modelReady: ready);
     notifyListeners();
   }
@@ -122,9 +137,18 @@ class CameraViewModel extends ChangeNotifier {
     for (final r in results) {
       if (r.score > highest) highest = r.score;
     }
+    if (lastProcessMs > 0) {
+      _procWindow.add(lastProcessMs);
+      if (_procWindow.length > latencyWindow) {
+        _procWindow.removeAt(0);
+      }
+    }
+    final latencyAvg = _procWindow.isEmpty
+        ? null
+        : _procWindow.reduce((a, b) => a + b) / _procWindow.length;
     _state = CameraUiState(
       modelReady: modelReady,
-      results: visible,
+      results: dedupeVisibleOverlaps(visible),
       rotation: rotation,
       imageWidthPx: imageWidthPx,
       imageHeightPx: imageHeightPx,
@@ -135,6 +159,7 @@ class CameraViewModel extends ChangeNotifier {
       framesReceived: framesReceived,
       debugLastMs: lastProcessMs,
       debugYuv: yuvDiag.isNotEmpty ? yuvDiag : _state.debugYuv,
+      latencyAvgMs: latencyAvg,
     );
     notifyListeners();
   }
@@ -161,6 +186,24 @@ class CameraViewModel extends ChangeNotifier {
           best = t;
         }
       }
+      // 跨标签同目标补挂（2026-09-03 用户实测修订：重叠位置只保留高置信度框）：
+      // 中心距超过跨标签收紧半径、但几何强重叠指向同一位置（不同模型对同一
+      // 目标的框偏移/紧致度不同）的检测并入既有轨迹，防止同目标两条轨迹并存
+      // → 同位置双名常驻/重复提醒。疑似↔目标（不同类别预警）不并入。
+      if (best == null) {
+        _Track? adopt;
+        var adoptD = double.infinity;
+        for (final t in _tracks.values) {
+          if (matched.contains(t.id)) continue;
+          if (t.isSuspect != r.isSuspect || !sameTarget(t.result, r)) continue;
+          final d = _centerDist(t.result, r);
+          if (d < adoptD) {
+            adoptD = d;
+            adopt = t;
+          }
+        }
+        best = adopt;
+      }
       if (best != null) {
         matched.add(best.id);
         best.update(r, now);
@@ -234,8 +277,30 @@ class _Track {
       : lastSeenMs = firstSeenMs,
         label = result.label;
 
+  /// 当前框是否疑似类别（随关联的最新检测更新——轨迹框在跨标签补挂后
+  /// 会换成其他标签的框；轨迹 label 仅创建时记账）
+  bool get isSuspect => result.isSuspect;
+
   void update(DetectionResult r, int now) {
     lastSeenMs = now;
     result = r;
   }
 }
+
+/// 同屏抑制（2026-09-03 用户实测修订：同一位置/重叠位置出现同/异模型检出的
+/// 物种只保留高置信度者）。根因：多个模型对同一目标**交替**检出时，每帧合并
+/// 层只压掉当帧低分框，但各自轨迹都落在 2s 忘记窗内持续显示 → 同位置双名
+/// 常驻。显示层兜底：可见框内同类别（都目标/都疑似）、且 [sameTarget] 强
+/// 重叠指向同一位置的框每帧只保留最高分者。异类别（目标×疑似生境预警）是
+/// 两种语义不同的框，同位置也各自保留。
+List<DetectionResult> dedupeVisibleOverlaps(List<DetectionResult> visible) {
+  if (visible.length <= 1) return visible;
+  final sorted = [...visible]..sort((a, b) => b.score.compareTo(a.score));
+  final kept = <DetectionResult>[];
+  for (final r in sorted) {
+    if (!kept.any((k) => k.isSuspect == r.isSuspect && sameTarget(k, r))) {
+      kept.add(r);
+    }
+  }
+  return kept;
+}

flutter_app/lib/camera/frame_analyzer.dart

@@ -12,8 +12,12 @@ class FrameAnalyzer {
   /// 连续检测：100ms 一帧
   int intervalMs = 100;
 
-  /// null = 模型加载失败，仅预览不分析
-  final DetectorWorker? worker;
+  DetectorWorker? _worker;
+
+  /// 当前推理 worker（null = 仅预览不分析）；相机启动后可用 [attachWorker]
+  /// 原地替换（相机帧流回调闭包捕获的是本 analyzer 对象，无需重启相机）
+  DetectorWorker? get worker => _worker;
+
   final CameraViewModel viewModel;
 
   int _lastDetectMs = 0;
@@ -29,9 +33,21 @@ class FrameAnalyzer {
   /// 图像流回调是否到达（诊断用）
   int framesReceived = 0;
 
-  FrameAnalyzer({required this.worker, required this.viewModel}) {
-    worker?.onResult = _onResult;
-    worker?.onError = _onError;
+  FrameAnalyzer({DetectorWorker? worker, required this.viewModel}) {
+    attachWorker(worker);
+  }
+
+  /// 替换推理 worker（null = 停识别仅预览）。旧 worker 在此释放；若相机已
+  /// 启动则新 worker 立即接管后续帧——重启相机会重新 initialize
+  /// （iOS ~1s+）且预览闪断，原地替换即时生效（2026-09-03）。
+  void attachWorker(DetectorWorker? w) {
+    if (identical(_worker, w)) return;
+    final old = _worker;
+    _worker = w;
+    w?.onResult = _onResult;
+    w?.onError = _onError;
+    old?.dispose();
+    _lastDetectMs = 0;
   }
 
   void recordStreamError(String msg) {
@@ -127,5 +143,5 @@ class FrameAnalyzer {
 
   void reset() => _lastDetectMs = 0;
 
-  void dispose() => worker?.dispose();
+  void dispose() => _worker?.dispose();
 }

flutter_app/lib/camera/model_catalog_section.dart

@@ -2,15 +2,24 @@ import 'package:flutter/material.dart';
 
 import '../models/model_manager.dart';
 
-/// 设置弹层「模型清单」区块：顶部「识别模式」分段控件（s 高识别 / n 高性能，
-/// 默认 s，持久化本地；切换即热加载该档位已激活模型），下方 2 列封面缩略图网格。
-/// 双档位：每数据集至多两张卡片（s/n 各一），卡片带档位角标；
-/// 卡片状态（下载进度/激活）按 (数据集, 档位) 独立记账。
+/// 档位展示名（档位码 s/n 仅内部记账，不对用户展示）
+String _variantLabel(String v) => v == kVariantN ? '高性能' : '高精度';
+
+/// 设置弹层「模型清单」区块：顶部「识别模式」分段控件（高性能 / 高精度，
+/// 默认高精度，持久化本地；2026-09-03 高性能移左位）选择**目标档位**——
+/// 只记录偏好，不直接切换运行中的模型，而是决定卡片按钮面向哪个档；下方
+/// 2 列封面缩略图网格，同一物种（datasetId）合并一张卡（s/n 两档内部记账，
+/// 各自下载独立进度）。
 ///
-/// 卡片状态机（档位 == 当前识别档位时与原单档行为一致）：
-/// - 未下载 →「使用/下载」：下载完成自动激活（当前档立即使用，非当前档备好待切）；
-/// - 已下载未激活 →「使用」直接激活；已激活且当前档 →「已使用」点击取消；
-/// - 已激活但属非当前档 →「已备好」（已下载就绪，点击切换到该档立即生效）。
+/// 同一物种一次只运行一个档位：启用某档会自动停用同物种另一档（不同物种可用
+/// 不同档位并行识别）。物种卡片主按钮（面向目标档，2026-09-03 简化文案——
+/// 一律「使用/使用中/下载」，不再叫「改用X」，不显示当前运行档提示）：
+/// - 任一档下载中 → 逐档进度条 + 取消（中止全部进行中的下载）；
+/// - 任一档失败 → 错误提示 + 重试（只补下未成功的档）；
+/// - 目标档已激活 →「使用中」点击取消使用；
+/// - 目标档已下载未激活 →「使用」直接启用（另一档在运行会被自动停用）；
+/// - 目标档未下载 →「下载」取回缺失档（目标档落地自动启用、伴档备好；
+///   另一档在使用时补下目标档后自动切换过去）。
 class ModelCatalogSection extends StatelessWidget {
   final ModelManager manager;
 
@@ -21,44 +30,57 @@ class ModelCatalogSection extends StatelessWidget {
     return ListenableBuilder(
       listenable: manager,
       builder: (context, _) {
-        // 目录行按 (数据集, 档位) 稳定排序：同数据集 s 前 n 后相邻展示
-        final items = [...manager.catalog]..sort((a, b) {
-            if (a.datasetId != b.datasetId) {
-              return a.datasetId.compareTo(b.datasetId);
-            }
-            return a.variant.compareTo(b.variant);
-          });
+        // 目录按数据集分组：同一物种 s/n 合成一张卡；组内 s（高精度）前 n 后
+        final byDataset = <int, List<ModelCatalogItem>>{};
+        for (final c in manager.catalog) {
+          byDataset.putIfAbsent(c.datasetId, () => []).add(c);
+        }
+        final groups = byDataset.values.toList()
+          ..sort((a, b) => a.first.datasetId.compareTo(b.first.datasetId));
+        final order = {kVariantS: 0, kVariantN: 1};
+        for (final g in groups) {
+          g.sort((a, b) =>
+              (order[a.variant] ?? 9).compareTo(order[b.variant] ?? 9));
+        }
         return Column(
           crossAxisAlignment: CrossAxisAlignment.start,
           mainAxisSize: MainAxisSize.min,
           children: [
             Row(
               children: [
-                const Text('识别模式',
-                    style: TextStyle(color: Colors.white70, fontSize: 14)),
+                const Text(
+                  '识别模式',
+                  style: TextStyle(color: Colors.white70, fontSize: 14),
+                ),
                 const Spacer(),
                 _ModeToggle(manager: manager),
               ],
             ),
             const SizedBox(height: 2),
-            const Text('切换即加载该档位已激活模型（激活状态跨档保留）',
-                style: TextStyle(color: Colors.white38, fontSize: 11)),
+            const Text(
+              '卡片操作面向所选档位；同一动物一次只运行一档，切换会自动停用另一档',
+              style: TextStyle(color: Colors.white38, fontSize: 11),
+            ),
             const SizedBox(height: 12),
             Row(
               children: [
-                const Text('模型清单',
-                    style: TextStyle(
-                        color: Colors.white,
-                        fontSize: 14,
-                        fontWeight: FontWeight.bold)),
+                const Text(
+                  '模型清单',
+                  style: TextStyle(
+                    color: Colors.white,
+                    fontSize: 14,
+                    fontWeight: FontWeight.bold,
+                  ),
+                ),
                 const Spacer(),
                 TextButton.icon(
                   onPressed: () => manager.refresh(),
                   icon: const Icon(Icons.refresh, size: 16),
                   label: const Text('刷新'),
                   style: TextButton.styleFrom(
-                      foregroundColor: Colors.white70,
-                      visualDensity: VisualDensity.compact),
+                    foregroundColor: Colors.white70,
+                    visualDensity: VisualDensity.compact,
+                  ),
                 ),
               ],
             ),
@@ -66,27 +88,29 @@ class ModelCatalogSection extends StatelessWidget {
             if (manager.error != null)
               Padding(
                 padding: const EdgeInsets.only(bottom: 8),
-                child: Text(manager.error!,
-                    style: const TextStyle(
-                        color: Colors.orange, fontSize: 12)),
+                child: Text(
+                  manager.error!,
+                  style: const TextStyle(color: Colors.orange, fontSize: 12),
+                ),
               ),
-            if (items.isEmpty)
-              const Text('暂无已发布模型',
-                  style: TextStyle(color: Colors.white54, fontSize: 13))
+            if (groups.isEmpty)
+              const Text(
+                '暂无已发布模型',
+                style: TextStyle(color: Colors.white54, fontSize: 13),
+              )
             else
               GridView.builder(
                 shrinkWrap: true,
                 physics: const NeverScrollableScrollPhysics(),
-                gridDelegate:
-                    const SliverGridDelegateWithFixedCrossAxisCount(
+                gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                   crossAxisCount: 2,
                   mainAxisSpacing: 12,
                   crossAxisSpacing: 12,
                   childAspectRatio: 0.72,
                 ),
-                itemCount: items.length,
+                itemCount: groups.length,
                 itemBuilder: (context, i) =>
-                    _ModelCard(item: items[i], manager: manager),
+                    _SpeciesCard(items: groups[i], manager: manager),
               ),
           ],
         );
@@ -95,12 +119,16 @@ class ModelCatalogSection extends StatelessWidget {
   }
 }
 
-/// 档位分段控件：s 高识别 / n 高性能
+/// 目标档位分段控件：高性能 / 高精度（2026-09-03 调换两档显示位置，
+/// 高性能在左、高精度在右；档位码 s/n 仅内部使用，不对用户展示）
 class _ModeToggle extends StatelessWidget {
   final ModelManager manager;
 
   const _ModeToggle({required this.manager});
 
+  /// 展示顺序（与内部档位常量解耦）
+  static const List<String> _displayOrder = [kVariantN, kVariantS];
+
   @override
   Widget build(BuildContext context) {
     return Container(
@@ -112,9 +140,9 @@ class _ModeToggle extends StatelessWidget {
       child: Row(
         mainAxisSize: MainAxisSize.min,
         children: [
-          for (final v in const [kVariantS, kVariantN]) ...[
-            if (v != kVariantS) const SizedBox(width: 2),
-            _seg(v),
+          for (var i = 0; i < _displayOrder.length; i++) ...[
+            if (i > 0) const SizedBox(width: 2),
+            _seg(_displayOrder[i]),
           ],
         ],
       ),
@@ -123,7 +151,6 @@ class _ModeToggle extends StatelessWidget {
 
   Widget _seg(String v) {
     final selected = manager.mode == v;
-    final label = v == kVariantS ? 's 高识别' : 'n 高性能';
     return InkWell(
       borderRadius: BorderRadius.circular(6),
       onTap: () => manager.setMode(v),
@@ -134,7 +161,7 @@ class _ModeToggle extends StatelessWidget {
           borderRadius: BorderRadius.circular(6),
         ),
         child: Text(
-          label,
+          _variantLabel(v),
           style: TextStyle(
             color: selected ? Colors.black : Colors.white70,
             fontSize: 12,
@@ -146,22 +173,35 @@ class _ModeToggle extends StatelessWidget {
   }
 }
 
-class _ModelCard extends StatelessWidget {
-  final ModelCatalogItem item;
+/// 单物种卡片：同数据集 s/n 两档合并；下载/激活状态按 (数据集, 档位) 独立记账，
+/// 同物种同时至多一个档位被激活（激活以目标档为准）
+class _SpeciesCard extends StatelessWidget {
+  final List<ModelCatalogItem> items;
   final ModelManager manager;
 
-  const _ModelCard({required this.item, required this.manager});
+  const _SpeciesCard({required this.items, required this.manager});
 
   @override
   Widget build(BuildContext context) {
-    final variant = item.variant;
-    final sameMode = manager.mode == variant;
-    final active = manager.isActive(item.datasetId, variant);
-    final downloaded = manager.isDownloaded(item.datasetId, variant);
-    final progress = manager.progressOf(item.datasetId, variant);
-    final error = manager.errorOf(item.datasetId, variant);
-    final accent =
-        variant == kVariantS ? Colors.greenAccent : Colors.orangeAccent;
+    // 目标条目：当前目标档优先；目录缺目标档（存量单档物种）时取 s 档
+    final target = items.firstWhere(
+      (i) => i.variant == manager.mode,
+      orElse: () => items.first,
+    );
+    final tActive = manager.isActive(target.datasetId, target.variant);
+    final tDownloaded = manager.isDownloaded(target.datasetId, target.variant);
+    // 同物种另一档正在使用的条目（至多一个——每数据集单档激活约束）
+    final activeOther = items
+        .where((i) =>
+            i.variant != target.variant &&
+            manager.isActive(i.datasetId, i.variant))
+        .toList();
+
+    // 任一档进行中/失败标志
+    final downloading =
+        items.any((i) => manager.progressOf(i.datasetId, i.variant) != null);
+    final hasError =
+        items.any((i) => manager.errorOf(i.datasetId, i.variant) != null);
 
     final thumb = ClipRRect(
       borderRadius: BorderRadius.circular(8),
@@ -171,41 +211,25 @@ class _ModelCard extends StatelessWidget {
           fit: StackFit.expand,
           children: [
             Image.network(
-              '${manager.baseUrl}${item.coverUrl}',
+              '${manager.baseUrl}${target.coverUrl}',
               fit: BoxFit.cover,
               loadingBuilder: (context, child, chunk) => chunk == null
                   ? child
                   : Container(
                       color: Colors.white12,
                       child: const Center(
-                          child: SizedBox(
-                              width: 20,
-                              height: 20,
-                              child: CircularProgressIndicator(
-                                  strokeWidth: 2)))),
+                        child: SizedBox(
+                          width: 20,
+                          height: 20,
+                          child: CircularProgressIndicator(strokeWidth: 2),
+                        ),
+                      ),
+                    ),
               errorBuilder: (context, error, stack) => Container(
                 color: Colors.white12,
-                child: const Icon(Icons.image_not_supported_outlined,
-                    color: Colors.white38),
-              ),
-            ),
-            // 档位角标：s 高识别（绿）/ n 高性能（橙）
-            Positioned(
-              top: 4,
-              left: 4,
-              child: Container(
-                padding:
-                    const EdgeInsets.symmetric(horizontal: 5, vertical: 1),
-                decoration: BoxDecoration(
-                  color: accent,
-                  borderRadius: BorderRadius.circular(4),
-                ),
-                child: Text(
-                  variant == kVariantS ? 's' : 'n',
-                  style: const TextStyle(
-                      color: Colors.black87,
-                      fontSize: 10,
-                      fontWeight: FontWeight.bold),
+                child: const Icon(
+                  Icons.image_not_supported_outlined,
+                  color: Colors.white38,
                 ),
               ),
             ),
@@ -214,110 +238,6 @@ class _ModelCard extends StatelessWidget {
       ),
     );
 
-    Widget action;
-    if (progress != null) {
-      action = Column(
-        mainAxisSize: MainAxisSize.min,
-        crossAxisAlignment: CrossAxisAlignment.stretch,
-        children: [
-          LinearProgressIndicator(
-              value: progress,
-              backgroundColor: Colors.white12,
-              color: Colors.greenAccent),
-          const SizedBox(height: 2),
-          Row(
-            children: [
-              Expanded(
-                child: Text(
-                  '${(progress * 100).toStringAsFixed(0)}%',
-                  textAlign: TextAlign.center,
-                  style:
-                      const TextStyle(color: Colors.white70, fontSize: 11),
-                ),
-              ),
-              TextButton(
-                onPressed: () =>
-                    manager.cancelDownload(item.datasetId, variant),
-                style: TextButton.styleFrom(
-                  foregroundColor: Colors.white54,
-                  visualDensity: VisualDensity.compact,
-                  padding: const EdgeInsets.symmetric(horizontal: 8),
-                  minimumSize: const Size(0, 24),
-                  tapTargetSize: MaterialTapTargetSize.shrinkWrap,
-                ),
-                child: const Text('取消', style: TextStyle(fontSize: 11)),
-              ),
-            ],
-          ),
-        ],
-      );
-    } else if (error != null) {
-      action = Column(
-        mainAxisSize: MainAxisSize.min,
-        children: [
-          Text(error,
-              maxLines: 1,
-              overflow: TextOverflow.ellipsis,
-              style: const TextStyle(color: Colors.redAccent, fontSize: 10)),
-          TextButton(
-            onPressed: () => manager.downloadModel(item),
-            child: const Text('重试', style: TextStyle(fontSize: 12)),
-          ),
-        ],
-      );
-    } else if (active && downloaded) {
-      if (sameMode) {
-        // 当前档已激活：点击取消
-        action = SizedBox(
-          height: 30,
-          child: OutlinedButton(
-            onPressed: () =>
-                manager.setActive(item.datasetId, variant, false),
-            style: OutlinedButton.styleFrom(
-                foregroundColor: Colors.greenAccent,
-                side: const BorderSide(color: Colors.greenAccent)),
-            child: const Text('已使用', style: TextStyle(fontSize: 12)),
-          ),
-        );
-      } else {
-        // 非当前档已备好（激活保留）：点击切换到该档立即生效
-        action = SizedBox(
-          height: 30,
-          child: OutlinedButton(
-            onPressed: () => manager.setMode(variant),
-            style: OutlinedButton.styleFrom(
-                foregroundColor: Colors.amberAccent,
-                side: const BorderSide(color: Colors.amberAccent)),
-            child: const Text('已备好', style: TextStyle(fontSize: 12)),
-          ),
-        );
-      }
-    } else if (downloaded) {
-      action = SizedBox(
-        height: 30,
-        child: FilledButton(
-          onPressed: () => manager.setActive(item.datasetId, variant, true),
-          style: FilledButton.styleFrom(
-              backgroundColor: Colors.greenAccent,
-              foregroundColor: Colors.black,
-              visualDensity: VisualDensity.compact),
-          child: const Text('使用', style: TextStyle(fontSize: 12)),
-        ),
-      );
-    } else {
-      action = SizedBox(
-        height: 30,
-        child: FilledButton(
-          onPressed: () => manager.downloadModel(item),
-          style: FilledButton.styleFrom(
-              backgroundColor: Colors.greenAccent,
-              foregroundColor: Colors.black,
-              visualDensity: VisualDensity.compact),
-          child: Text(sameMode ? '使用' : '下载', style: const TextStyle(fontSize: 12)),
-        ),
-      );
-    }
-
     return Container(
       padding: const EdgeInsets.all(8),
       decoration: BoxDecoration(
@@ -332,35 +252,226 @@ class _ModelCard extends StatelessWidget {
           Row(
             children: [
               Expanded(
-                child: Text(item.datasetName,
-                    maxLines: 1,
-                    overflow: TextOverflow.ellipsis,
-                    style: const TextStyle(
-                        color: Colors.white,
-                        fontSize: 13,
-                        fontWeight: FontWeight.w600)),
-              ),
-              Container(
-                padding:
-                    const EdgeInsets.symmetric(horizontal: 4, vertical: 1),
-                decoration: BoxDecoration(
-                  color: accent.withValues(alpha: 0.25),
-                  borderRadius: BorderRadius.circular(4),
-                ),
                 child: Text(
-                  variant == kVariantS ? '高识别' : '高性能',
-                  style: TextStyle(color: accent, fontSize: 9),
+                  target.datasetName,
+                  maxLines: 1,
+                  overflow: TextOverflow.ellipsis,
+                  style: const TextStyle(
+                    color: Colors.white,
+                    fontSize: 13,
+                    fontWeight: FontWeight.w600,
+                  ),
                 ),
               ),
             ],
           ),
           const SizedBox(height: 2),
-          Text('v${item.version}',
-              style: const TextStyle(color: Colors.white38, fontSize: 10)),
+          // 双档行：高精度 / 高性能各自版本号；使用中绿色高亮、已下载次之、缺失置灰
+          Text.rich(
+            TextSpan(
+              children: [
+                for (final i in items) ...[
+                  if (i != items.first) const TextSpan(text: '  ·  '),
+                  TextSpan(
+                    text: '${_variantLabel(i.variant)} ${i.version}',
+                    style: TextStyle(
+                      fontSize: 9,
+                      color: manager.isActive(i.datasetId, i.variant)
+                          ? Colors.greenAccent
+                          : manager.isDownloaded(i.datasetId, i.variant)
+                              ? Colors.white70
+                              : Colors.white38,
+                      fontWeight: manager.isActive(i.datasetId, i.variant)
+                          ? FontWeight.bold
+                          : FontWeight.normal,
+                    ),
+                  ),
+                ],
+              ],
+            ),
+          ),
           const SizedBox(height: 6),
-          action,
+          _actionArea(
+            items: items,
+            target: target,
+            downloading: downloading,
+            hasError: hasError,
+            tActive: tActive,
+            tDownloaded: tDownloaded,
+            activeOther: activeOther,
+          ),
         ],
       ),
     );
   }
+
+  /// 动作区：进度/错误优先级最高；其次按目标档的下载/激活状态给主按钮
+  Widget _actionArea({
+    required List<ModelCatalogItem> items,
+    required ModelCatalogItem target,
+    required bool downloading,
+    required bool hasError,
+    required bool tActive,
+    required bool tDownloaded,
+    required List<ModelCatalogItem> activeOther,
+  }) {
+    if (downloading) {
+      return Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          for (final i in items)
+            if (manager.progressOf(i.datasetId, i.variant) != null)
+              _progressRow(item: i),
+          Align(
+            alignment: Alignment.centerRight,
+            child: TextButton(
+              onPressed: () {
+                for (final i in items) {
+                  if (manager.progressOf(i.datasetId, i.variant) != null) {
+                    manager.cancelDownload(i.datasetId, i.variant);
+                  }
+                }
+              },
+              style: TextButton.styleFrom(
+                foregroundColor: Colors.white54,
+                visualDensity: VisualDensity.compact,
+                padding: const EdgeInsets.symmetric(horizontal: 8),
+                minimumSize: const Size(0, 24),
+                tapTargetSize: MaterialTapTargetSize.shrinkWrap,
+              ),
+              child: const Text('取消', style: TextStyle(fontSize: 11)),
+            ),
+          ),
+        ],
+      );
+    }
+    if (hasError) {
+      return Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          for (final i in items)
+            if (manager.errorOf(i.datasetId, i.variant) != null)
+              Text(
+                '${_variantLabel(i.variant)}下载失败',
+                maxLines: 1,
+                overflow: TextOverflow.ellipsis,
+                style: const TextStyle(
+                    color: Colors.redAccent, fontSize: 10),
+              ),
+          Align(
+            alignment: Alignment.centerRight,
+            child: TextButton(
+              onPressed: () {
+                for (final i in items) {
+                  if (manager.errorOf(i.datasetId, i.variant) != null) {
+                    manager.downloadModel(i);
+                  }
+                }
+              },
+              style: TextButton.styleFrom(
+                foregroundColor: Colors.redAccent,
+                visualDensity: VisualDensity.compact,
+                padding: const EdgeInsets.symmetric(horizontal: 8),
+                minimumSize: const Size(0, 24),
+                tapTargetSize: MaterialTapTargetSize.shrinkWrap,
+              ),
+              child: const Text('重试', style: TextStyle(fontSize: 11)),
+            ),
+          ),
+        ],
+      );
+    }
+
+    final Widget mainBtn;
+    if (tActive) {
+      // 目标档使用中：点击取消使用
+      mainBtn = SizedBox(
+        height: 30,
+        child: OutlinedButton(
+          onPressed: () =>
+              manager.setActive(target.datasetId, target.variant, false),
+          style: OutlinedButton.styleFrom(
+            foregroundColor: Colors.greenAccent,
+            side: const BorderSide(color: Colors.greenAccent),
+          ),
+          child: const Text('使用中', style: TextStyle(fontSize: 12)),
+        ),
+      );
+    } else if (tDownloaded) {
+      // 已下载未激活（目标档）：点「使用」直接启用——同物种另一档在使用会被
+      // 自动停用（每数据集至多一档运行），统一文案不再叫「改用X」（2026-09-03）
+      mainBtn = SizedBox(
+        height: 30,
+        child: FilledButton(
+          onPressed: () =>
+              manager.setActive(target.datasetId, target.variant, true),
+          style: FilledButton.styleFrom(
+            backgroundColor: Colors.greenAccent,
+            foregroundColor: Colors.black,
+            visualDensity: VisualDensity.compact,
+          ),
+          child: const Text('使用', style: TextStyle(fontSize: 12)),
+        ),
+      );
+    } else {
+      // 目标档未下载：下载全部缺失档（目标档落地自动启用、伴档备好待切）；
+      // 另一档在使用时按钮同样为「下载」：补下目标档后自动切换（停用另一档）
+      final use = activeOther.isNotEmpty;
+      mainBtn = SizedBox(
+        height: 30,
+        child: FilledButton(
+          onPressed: () async {
+            if (!use) {
+              for (final i in items) {
+                if (!manager.isDownloaded(i.datasetId, i.variant)) {
+                  manager.downloadModel(i);
+                }
+              }
+              return;
+            }
+            if (!manager.isDownloaded(target.datasetId, target.variant)) {
+              final ok = await manager.downloadModel(target);
+              if (!ok) return; // 下载失败/取消：错误分支展示，保持现状
+            }
+            await manager.setActive(target.datasetId, target.variant, true);
+          },
+          style: FilledButton.styleFrom(
+            backgroundColor: Colors.greenAccent,
+            foregroundColor: Colors.black,
+            visualDensity: VisualDensity.compact,
+          ),
+          child: const Text('下载', style: TextStyle(fontSize: 12)),
+        ),
+      );
+    }
+
+    return Column(
+      mainAxisSize: MainAxisSize.min,
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [mainBtn],
+    );
+  }
+
+  Widget _progressRow({required ModelCatalogItem item}) {
+    final p = manager.progressOf(item.datasetId, item.variant) ?? 0.0;
+    final label = _variantLabel(item.variant);
+    return Column(
+      mainAxisSize: MainAxisSize.min,
+      children: [
+        Row(
+          children: [
+            Text(
+              '$label ${(p * 100).toStringAsFixed(0)}%',
+              style: const TextStyle(color: Colors.white70, fontSize: 10),
+            ),
+          ],
+        ),
+        LinearProgressIndicator(
+          value: p,
+          backgroundColor: Colors.white12,
+          color: Colors.greenAccent,
+        ),
+      ],
+    );
+  }
 }