1

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();
 }