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packages/view_model/CHANGELOG.md

@@ -1,3 +1,10 @@
+## 1.0.2
+- Fix listener mutation safety during notification dispatch.
+- Fix recreate failure handling to keep previous instance valid.
+- Fix disposal cleanup in instance manager and pause providers.
+- Improve cached access error handling and DevTools active state reporting.
+- Internal cleanup: remove duplicated binding extension implementations.
+
 ## 1.0.1
 - Fix: DevToolsService not clearing singleton `_instance` on dispose
 - Fix: typo "suucess" → "success" in DevToolsService log

packages/view_model/analysis_options.yaml

@@ -1,6 +1,10 @@
 # Additional information about this file can be found at
 # https://dart.dev/guides/language/analysis-options
 
+analyzer:
+  exclude:
+    - example/**
+
 linter:
   # The lint rules applied to this project can be customized in the
   # section below to disable rules from the `package:flutter_lints/flutter.yaml`

packages/view_model/lib/src/devtool/service.dart

@@ -205,7 +205,7 @@ class DevToolsService {
                 'id': vm.instanceId,
                 'type': vm.typeName,
                 'label': '${vm.typeName}\n${vm.key ?? vm.instanceId}',
-                'isActive': true,
+                'isActive': !vm.isDisposed,
               })
           .toList(),
       'edges': dependencies,

packages/view_model/lib/src/get_instance/auto_dispose.dart

@@ -162,7 +162,7 @@ class AutoDisposeInstanceController {
   /// the given action to each ViewModel instance.
   void performForAllInstances(void Function(ViewModel viewModel) action) {
     for (final notifier in _instanceNotifiers) {
-      if (notifier.instance is ViewModel) {
+      if (!notifier.isDisposed && notifier.instance is ViewModel) {
         action(notifier.instance as ViewModel);
       }
     }
@@ -184,7 +184,11 @@ class AutoDisposeInstanceController {
   /// ```
   void recycle(Object instance) {
     _instanceNotifiers.removeWhere((e) {
-      if (e.instance == instance) {
+      if (!e.isDisposed && e.instance == instance) {
+        final listener = _notifierListeners.remove(e);
+        if (listener != null) {
+          e.removeListener(listener);
+        }
         e.unbindAll();
         return true;
       } else {
@@ -199,7 +203,7 @@ class AutoDisposeInstanceController {
   /// binders remain, the instance can be recycled automatically.
   void unbindInstance(Object instance) {
     for (final e in _instanceNotifiers) {
-      if (e.instance == instance) {
+      if (!e.isDisposed && e.instance == instance) {
         e.unbind(viewModelBinding.id);
         break;
       }
@@ -227,10 +231,12 @@ class AutoDisposeInstanceController {
       if (!e.isDisposed && e.instance is ViewModel) {
         (e.instance as ViewModel).refHandler.removeRef(viewModelBinding);
       }
-      e.unbind(viewModelBinding.id);
+      // Remove listener before unbind, because unbind may trigger _recycle()
+      // which disposes the ChangeNotifier, making removeListener fail.
       if (_notifierListeners.containsKey(e)) {
         e.removeListener(_notifierListeners[e]!);
       }
+      e.unbind(viewModelBinding.id);
     }
     _notifierListeners.clear();
     _instanceNotifiers.clear();

packages/view_model/lib/src/get_instance/manager.dart

@@ -8,6 +8,7 @@
 /// @author luwenjie on 2025/3/25 12:23:33
 library;
 
+import 'package:flutter/foundation.dart';
 import 'package:view_model/src/view_model/state_store.dart';
 
 import 'store.dart';
@@ -52,7 +53,11 @@ class InstanceManager {
     T t, {
     T Function()? builder,
   }) {
-    final Store<T> s = _stores[T];
+    final store = _stores[T];
+    if (store is! Store<T>) {
+      throw ViewModelError("Cannot recreate $T instance. Store not found.");
+    }
+    final Store<T> s = store;
     return s.recreate(
       t,
       builder: builder,
@@ -78,10 +83,22 @@ class InstanceManager {
   ///
   /// Returns the [Store] instance for type [T].
   Store<T> _getStore<T>() {
-    Store<T>? s = _stores[T];
-    s ??= Store<T>();
-    _stores[T] = s;
-    return s;
+    final cached = _stores[T];
+    if (cached is Store<T>) {
+      return cached;
+    }
+
+    late final Store<T> created;
+    created = Store<T>(
+      onStoreEmpty: () {
+        final current = _stores[T];
+        if (!identical(current, created) || !created.isEmpty) return;
+        _stores.remove(T);
+        created.dispose();
+      },
+    );
+    _stores[T] = created;
+    return created;
   }
 
   /// Gets a ViewModel instance directly.
@@ -175,6 +192,12 @@ class InstanceManager {
     }
     return _getStore<T>().getInstancesByTag(tag);
   }
+
+  @visibleForTesting
+  int get debugStoreCount => _stores.length;
+
+  @visibleForTesting
+  bool debugHasStoreFor<T>() => _stores[T] != null;
 }
 
 /// Factory configuration for ViewModel instance creation and retrieval.

packages/view_model/lib/src/get_instance/store.dart

@@ -36,11 +36,18 @@ class _Undefined {
 /// The store maintains a map of instances keyed by their unique identifiers
 /// and automatically handles cleanup when instances are no longer needed.
 class Store<T> {
+  Store({void Function()? onStoreEmpty}) : _onStoreEmpty = onStoreEmpty;
+
+  final void Function()? _onStoreEmpty;
+
   /// Stream controller for broadcasting instance creation events.
   final _streamController = StreamController<InstanceHandle<T>>.broadcast();
 
   /// Map of cached instances keyed by their unique identifiers.
   final Map<Object, InstanceHandle<T>> _instances = {};
+  bool _disposed = false;
+
+  bool get isEmpty => _instances.isEmpty;
 
   /// Finds the most recently created instance, optionally filtered by tag.
   ///
@@ -106,6 +113,9 @@ class Store<T> {
         case InstanceAction.dispose:
           _instances.remove(notifier.arg.key);
           notifier.removeListener(onNotify);
+          if (_instances.isEmpty) {
+            _onStoreEmpty?.call();
+          }
           break;
         case InstanceAction.recreate:
           break;
@@ -136,6 +146,9 @@ class Store<T> {
   /// Throws [ViewModelError] if no cached instance exists and no
   /// builder is provided.
   InstanceHandle<T> getNotifier({required InstanceFactory<T> factory}) {
+    if (_disposed) {
+      throw ViewModelError("Store<$T> has been disposed.");
+    }
     final realKey = factory.arg.key ?? Object();
     final bindingId = factory.arg.bindingId;
     final arg = factory.arg.copyWith(
@@ -199,6 +212,13 @@ class Store<T> {
     );
     return find.recreate(builder: builder);
   }
+
+  void dispose() {
+    if (_disposed) return;
+    _disposed = true;
+    _instances.clear();
+    _streamController.close();
+  }
 }
 
 /// Handle for managing a ViewModel instance and its lifecycle.
@@ -235,6 +255,7 @@ class InstanceHandle<T> with ChangeNotifier {
 
   /// The actual ViewModel instance (null when disposed).
   late T? _instance;
+  bool _disposed = false;
 
   bool get isDisposed => _instance == null;
 
@@ -334,8 +355,14 @@ class InstanceHandle<T> with ChangeNotifier {
   T recreate({
     T Function()? builder,
   }) {
-    onDispose();
-    _instance = (builder?.call()) ?? factory.call();
+    final previous = _instance;
+    if (previous == null) {
+      throw ViewModelError(
+          "Cannot recreate $T instance. Instance is disposed.");
+    }
+    final recreated = (builder?.call()) ?? factory.call();
+    _tryCallInstanceDispose(previous);
+    _instance = recreated;
     onCreate(arg);
     _action = InstanceAction.recreate;
     notifyListeners();
@@ -367,12 +394,12 @@ class InstanceHandle<T> with ChangeNotifier {
   /// This method attempts to call the onDispose lifecycle method if the
   /// instance implements [InstanceLifeCycle]. Errors are logged but don't
   /// prevent the disposal process.
-  void _tryCallInstanceDispose() {
-    if (_instance is InstanceLifeCycle) {
+  void _tryCallInstanceDispose(Object? target) {
+    if (target is InstanceLifeCycle) {
       try {
-        (_instance as InstanceLifeCycle).onDispose(arg);
+        target.onDispose(arg);
       } catch (e) {
-        viewModelLog("${_instance.runtimeType} onDispose error $e");
+        viewModelLog("${target.runtimeType} onDispose error $e");
       }
     }
   }
@@ -382,8 +409,11 @@ class InstanceHandle<T> with ChangeNotifier {
   /// This method calls the instance's disposal lifecycle method,
   /// clears all watchers, and nullifies the instance reference.
   void onDispose() {
-    _tryCallInstanceDispose();
+    if (_disposed) return;
+    _disposed = true;
+    _tryCallInstanceDispose(_instance);
     _instance = null;
+    super.dispose();
   }
 }
 

packages/view_model/lib/src/view_model/pause_provider.dart

@@ -45,10 +45,9 @@ class AppPauseProvider with ViewModelBindingPauseProvider {
 
   @override
   void dispose() {
-    super.dispose();
     _subscription?.cancel();
     _subscription = null;
-    _controller.close();
+    super.dispose();
   }
 }
 
@@ -80,9 +79,9 @@ class TickerModePauseProvider with ViewModelBindingPauseProvider {
 
   @override
   void dispose() {
-    super.dispose();
     _notifier?.removeListener(_onChange);
     _notifier = null;
+    super.dispose();
   }
 }
 
@@ -120,8 +119,8 @@ class PageRoutePauseProvider with ViewModelBindingPauseProvider, RouteAware {
 
   @override
   void dispose() {
-    super.dispose();
     unsubscribe(_observer);
+    super.dispose();
   }
 
   @override

packages/view_model/lib/src/view_model/view_model.dart

@@ -79,7 +79,8 @@ class ChangeNotifierViewModel extends ChangeNotifier with ViewModel {}
 ///   }
 /// }
 /// ```
-mixin class ViewModel implements InstanceLifeCycle, Listenable {
+mixin class ViewModel
+    implements InstanceLifeCycle, Listenable, ViewModelBindingHost {
   /// Returns the [ViewModelBinding] interface for accessing other ViewModels.
   ///
   /// This property allows you to use
@@ -135,7 +136,7 @@ mixin class ViewModel implements InstanceLifeCycle, Listenable {
   static T? maybeReadCached<T extends ViewModel>({Object? key, Object? tag}) {
     try {
       return readCached<T>(key: key, tag: tag);
-    } catch (e) {
+    } on ViewModelError {
       return null;
     }
   }
@@ -376,7 +377,9 @@ mixin class ViewModel implements InstanceLifeCycle, Listenable {
   /// is provided, errors are logged. This prevents one listener from
   /// affecting others.
   void notifyListeners() {
-    for (final element in _listeners) {
+    final listeners = List<VoidCallback>.of(_listeners);
+    for (final element in listeners) {
+      if (!_listeners.contains(element)) continue;
       try {
         element.call();
       } catch (e, stack) {
@@ -634,7 +637,10 @@ abstract class StateViewModel<T> with ViewModel {
     if (_isDisposed) return;
 
     // Phase 1: Notify state listeners with previous and current state
-    for (final element in _stateListeners) {
+    final stateListeners =
+        List<Function(T? previous, T state)>.of(_stateListeners);
+    for (final element in stateListeners) {
+      if (!_stateListeners.contains(element)) continue;
       try {
         element.call(event.previousState, event.currentState);
       } catch (e, stack) {
@@ -648,7 +654,9 @@ abstract class StateViewModel<T> with ViewModel {
     }
 
     // Phase 2: Notify general listeners
-    for (final element in _listeners) {
+    final listeners = List<VoidCallback>.of(_listeners);
+    for (final element in listeners) {
+      if (!_listeners.contains(element)) continue;
       try {
         element.call();
       } catch (e, stack) {