enhanced-change-notifier

name	enhanced_change_notifier
description	Use when coding with enhanced_change_notifier: targeted property notifications, once/immediate listeners, GlobalFactory singletons, EnhancedValueNotifier, Signal, and EnhancedLatchNotifier delayed release patterns.

enhanced_change_notifier Agent Context

Use this package when Flutter state needs targeted property notifications beyond core ChangeNotifier, or when listeners should be one-shot/immediate.

Imports

import 'package:enhanced_change_notifier/enhanced_change_notifier.dart';
import 'package:enhanced_change_notifier/enhanced_value_notifier.dart';
import 'package:enhanced_change_notifier/signal.dart';

EnhancedChangeNotifier

class AppModel extends EnhancedChangeNotifier {
  AppModel() {
    fromMap({"token": "initial-token"}); // silent init
  }

  String? get token => this["token"];
  set token(String? value) {
    this["token"] = value; // stores and notifies target "token"
  }

  void silentToken(String? value) {
    fromMap({"token": value});
    notifyListeners("token");
  }
}

final GlobalFactory<AppModel> appStateModel =
    GlobalFactory(() => AppModel());

void anyChanged() {}

final model = appStateModel.getInstance();
model.addListener(anyChanged);
model.addListener((String property) {}, target: "token");
model.addListener((String property) {}, target: "token", once: true);
model.addListener((String property) {}, target: "token", immediate: true);
model.token = "new-token";
model.removeListener(anyChanged);

Signal

Signal caches pending callbacks until released.

final isConsumerReady = Signal()..value = false;
isConsumerReady.promise(() => print("Task executed"));
Future.delayed(const Duration(milliseconds: 300), () {
  isConsumerReady.value = true;
});

EnhancedLatchNotifier

Use latch notification when a non-bool event should be stored until unlatch().

class LatchStateEvent {
  final String actionId;
  final int value;
  LatchStateEvent(this.actionId, this.value);
}

class DelayedLatch extends EnhancedLatchNotifier<LatchStateEvent> {}

final latch = GlobalFactory<DelayedLatch>(() => DelayedLatch()).getInstance();
latch.addListener((event) {
  if (event.actionId == "test") print(event.value);
});
latch.fire(LatchStateEvent("test", 99));
latch.unlatch();

Notes for Agents

• Use this["property"] = value for notifying property-specific listeners.
• Use fromMap for silent bulk updates; call notifyListeners("property") manually when needed.
• Use target for property-specific listeners, once for one-shot listeners, immediate for instant initial callbacks.
• Use GlobalFactory<T> for app-wide singleton model instances.