1

flutter_app/lib/camera/camera_screen.dart

@@ -12,6 +12,7 @@ import 'app_camera_controller.dart';
 import 'camera_view_model.dart';
 import 'detection_overlay.dart';
 import 'frame_analyzer.dart';
+import 'model_catalog_section.dart';
 
 /// 主界面：相机预览 + 检测框 overlay + 顶栏(返回/切换摄像头)
 class CameraScreen extends StatefulWidget {
@@ -40,50 +41,61 @@ class _CameraScreenState extends State<CameraScreen> {
   void _openSettings() {
     final vm = _viewModel;
     if (vm == null) return;
+    ModelManager.instance.refresh();
     showModalBottomSheet<void>(
       context: context,
+      isScrollControlled: true,
       backgroundColor: Colors.black87,
       builder: (ctx) => StatefulBuilder(
-        builder: (ctx, setSheetState) => 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('${(_minScore * 100).toStringAsFixed(0)}%',
-                      style: const TextStyle(
-                          color: Colors.greenAccent,
-                          fontSize: 14,
-                          fontWeight: FontWeight.bold)),
-                ],
-              ),
-              Slider(
-                value: _minScore,
-                min: 0.05,
-                max: 0.50,
-                divisions: 45,
-                activeColor: Colors.greenAccent,
-                onChanged: (v) {
-                  setSheetState(() => _minScore = v);
-                  _analyzer?.worker?.setMinScore(v);
-                },
-              ),
-              const SizedBox(height: 8),
-              const Text(
-                '阈值越低识别越灵敏（低分框越多，误报也可能增加）；'
-                '环颈雉鸡模型置信度普遍在 10%~20%，场景识别不到时可适当调低。',
-                style: TextStyle(color: Colors.white54, fontSize: 12),
-              ),
-            ],
+        builder: (ctx, setSheetState) => SingleChildScrollView(
+          child: Padding(
+            padding: const EdgeInsets.all(20),
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                const Text('识别设置',
+                    style: TextStyle(
+                        color: Colors.white,
+                        fontSize: 16,
+                        fontWeight: FontWeight.bold)),
+                const SizedBox(height: 12),
+                Row(
+                  children: [
+                    const Text('置信度阈值',
+                        style:
+                            TextStyle(color: Colors.white70, fontSize: 14)),
+                    const Spacer(),
+                    Text('${(_minScore * 100).toStringAsFixed(0)}%',
+                        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）；'
+                  '环颈雉鸡模型置信度普遍在 10%~20%，场景识别不到时可适当调低。',
+                  style: TextStyle(color: Colors.white54, fontSize: 12),
+                ),
+                const SizedBox(height: 16),
+                const Divider(color: Colors.white12),
+                const SizedBox(height: 8),
+                ModelCatalogSection(manager: ModelManager.instance),
+              ],
+            ),
           ),
         ),
       ),

flutter_app/lib/camera/model_catalog_section.dart

@@ -0,0 +1,225 @@
+import 'package:flutter/material.dart';
+
+import '../models/model_manager.dart';
+
+/// 设置弹层「模型清单」区块：2 列封面缩略图网格。
+/// 未下载 →「使用」点击后显示下载进度，完成自动激活；已下载未激活 → 直接激活；
+/// 已激活 → 再次点击取消；下载失败 → 失败提示 + 重试。
+class ModelCatalogSection extends StatelessWidget {
+  final ModelManager manager;
+
+  const ModelCatalogSection({super.key, required this.manager});
+
+  @override
+  Widget build(BuildContext context) {
+    return ListenableBuilder(
+      listenable: manager,
+      builder: (context, _) {
+        final items = manager.catalog;
+        return Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            Row(
+              children: [
+                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),
+                ),
+              ],
+            ),
+            const SizedBox(height: 4),
+            if (manager.error != null)
+              Padding(
+                padding: const EdgeInsets.only(bottom: 8),
+                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))
+            else
+              GridView.builder(
+                shrinkWrap: true,
+                physics: const NeverScrollableScrollPhysics(),
+                gridDelegate:
+                    const SliverGridDelegateWithFixedCrossAxisCount(
+                  crossAxisCount: 2,
+                  mainAxisSpacing: 12,
+                  crossAxisSpacing: 12,
+                  childAspectRatio: 0.72,
+                ),
+                itemCount: items.length,
+                itemBuilder: (context, i) =>
+                    _ModelCard(item: items[i], manager: manager),
+              ),
+          ],
+        );
+      },
+    );
+  }
+}
+
+class _ModelCard extends StatelessWidget {
+  final ModelCatalogItem item;
+  final ModelManager manager;
+
+  const _ModelCard({required this.item, required this.manager});
+
+  @override
+  Widget build(BuildContext context) {
+    final active = manager.isActive(item.datasetId);
+    final downloaded = manager.isDownloaded(item.datasetId);
+    final progress = manager.progressOf(item.datasetId);
+    final error = manager.errorOf(item.datasetId);
+
+    final thumb = ClipRRect(
+      borderRadius: BorderRadius.circular(8),
+      child: AspectRatio(
+        aspectRatio: 4 / 3,
+        child: Image.network(
+          '${manager.baseUrl}${item.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)))),
+          errorBuilder: (context, error, stack) => Container(
+            color: Colors.white12,
+            child: const Icon(Icons.image_not_supported_outlined,
+                color: Colors.white38),
+          ),
+        ),
+      ),
+    );
+
+    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),
+                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) {
+      action = SizedBox(
+        height: 30,
+        child: OutlinedButton(
+          onPressed: () => manager.setActive(item.datasetId, false),
+          style: OutlinedButton.styleFrom(
+              foregroundColor: Colors.greenAccent,
+              side: const BorderSide(color: Colors.greenAccent)),
+          child: const Text('已使用', style: TextStyle(fontSize: 12)),
+        ),
+      );
+    } else if (downloaded) {
+      action = SizedBox(
+        height: 30,
+        child: FilledButton(
+          onPressed: () => manager.setActive(item.datasetId, 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: const Text('使用', style: TextStyle(fontSize: 12)),
+        ),
+      );
+    }
+
+    return Container(
+      padding: const EdgeInsets.all(8),
+      decoration: BoxDecoration(
+        color: Colors.white10,
+        borderRadius: BorderRadius.circular(10),
+      ),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Expanded(child: Center(child: thumb)),
+          const SizedBox(height: 6),
+          Text(item.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)),
+          const SizedBox(height: 6),
+          action,
+        ],
+      ),
+    );
+  }
+}

flutter_app/lib/models/model_manager.dart

@@ -81,6 +81,7 @@ class ModelManager extends ChangeNotifier {
   final Set<int> _downloadedIds = {};
   final Map<int, double> _progress = {};
   final Map<int, String> _errors = {};
+  final Set<int> _cancelRequested = {};
   bool _activeLoaded = false;
   bool _ready = false;
   bool _refreshing = false;
@@ -104,6 +105,12 @@ class ModelManager extends ChangeNotifier {
   /// 下载失败原因（失败后可重试）
   String? errorOf(int datasetId) => _errors[datasetId];
 
+  /// 中断进行中的下载：下一个数据块到达时终止（丢弃 .part），卡片恢复「使用」。
+  /// 取消不记错误，可再次下载。
+  void cancelDownload(int datasetId) {
+    _cancelRequested.add(datasetId);
+  }
+
   ModelManager._({String? baseUrl, http.Client? client})
       : this(baseUrl: baseUrl, client: client);
 
@@ -209,11 +216,13 @@ class ModelManager extends ChangeNotifier {
     // 并发保护：同一数据集已有进行中的下载则直接短路（预置 0 先占位，
     // 使 onProgress 首次回调前的双击/refresh 交错也被 containsKey 拦下）
     if (_progress.containsKey(item.datasetId)) return false;
+    _cancelRequested.remove(item.datasetId);
     _progress[item.datasetId] = 0;
     final dir = await _modelDir(item.datasetId);
     final file = File('${dir.path}/model.tflite');
     try {
       for (var attempt = 0; attempt < 2; attempt++) {
+        if (_cancelRequested.contains(item.datasetId)) break;
         final ok = await _downloadAndVerify(item, dir, file,
             onProgress: (r, t) {
           _progress[item.datasetId] = t == 0 ? 0 : r / t;
@@ -227,17 +236,39 @@ class ModelManager extends ChangeNotifier {
           await setActive(item.datasetId, true);
           return true;
         }
+        if (_cancelRequested.contains(item.datasetId)) break;
         await file.delete().catchError((_) => file);
         await File('${dir.path}/model.tflite.part')
             .delete()
             .catchError((_) => file);
       }
+      if (_cancelRequested.contains(item.datasetId)) {
+        // 用户取消：清理残留，不记错误
+        await file.delete().catchError((_) => file);
+        await File('${dir.path}/model.tflite.part')
+            .delete()
+            .catchError((_) => file);
+        _progress.remove(item.datasetId);
+        notifyListeners();
+        debugPrint('[ModelManager] 下载已取消: ${item.datasetName}');
+        return false;
+      }
       _progress.remove(item.datasetId);
       _errors[item.datasetId] = '下载失败，请重试';
       notifyListeners();
       debugPrint('[ModelManager] 下载失败: ${item.datasetName} ${item.version}');
       return false;
     } catch (e) {
+      if (_cancelRequested.contains(item.datasetId)) {
+        await file.delete().catchError((_) => file);
+        await File('${dir.path}/model.tflite.part')
+            .delete()
+            .catchError((_) => file);
+        _progress.remove(item.datasetId);
+        notifyListeners();
+        debugPrint('[ModelManager] 下载已取消: ${item.datasetName}');
+        return false;
+      }
       _progress.remove(item.datasetId);
       _errors[item.datasetId] = '下载异常:$e';
       notifyListeners();
@@ -262,10 +293,15 @@ class ModelManager extends ChangeNotifier {
       }
       final total = res.contentLength ?? item.sizeBytes;
       await for (final chunk in res.stream) {
+        if (_cancelRequested.contains(item.datasetId)) break; // 用户取消
         sink.add(chunk);
         received += chunk.length;
         onProgress?.call(received, total);
       }
+      if (_cancelRequested.contains(item.datasetId)) {
+        await sink.close();
+        return false;
+      }
       await sink.close();
       final bytes = await part.readAsBytes();
       final hex = sha256.convert(bytes).toString();