enhanced_change_notifier 1.0.0
enhanced_change_notifier: ^1.0.0 copied to clipboard
A enhanced version of ChangeNotifier introduces new features `target`, `once`, and `immediate`.
import 'package:enhanced_change_notifier/enhanced_change_notifier.dart';
import 'package:enhanced_change_notifier/signal.dart';
import 'package:enhanced_change_notifier/src/enhanced_latch_notifier.dart';
class AppModel extends EnhancedChangeNotifier {
String? get token => super.properties["token"];
set token(String? token) {
super.properties["token"] = token;
}
String? get baseUrl => super.properties["baseUrl"];
set baseUrl(String? baseUrl) {
super.properties["baseUrl"] = baseUrl;
}
Map<String, dynamic> get tasks => super.properties["tasks"];
set tasks(Map<String, dynamic> tasks) {
super.properties["tasks"] = tasks;
}
}
class LatchStateEvent {
String actionId;
int value;
LatchStateEvent(this.actionId, this.value);
}
class DelayedLatch extends EnhancedLatchNotifier<LatchStateEvent> {}
void main() {
// 1. AppModel extends EnhancedChangeNotifier example
final GlobalFactory<AppModel> appStateModel = GlobalFactory(() => AppModel());
// Register different types of listeners, support target, once, immediate
appStateModel
.getInstance()
.addListener(() => print('any property changed in AppModel'));
appStateModel.getInstance().addListener(
(String property) => print('$property changed in AppModel'),
target: ['token', 'baseUrl', 'tasks']);
appStateModel.getInstance().addListener(
(String property, Object? value) =>
print('$property changed to $value in AppModel'),
target: 'token');
appStateModel.getInstance().addListener(
(String property) => print(
'$property changed in AppModel, listener would be triggered only once'),
target: 'baseUrl',
once: true);
appStateModel.getInstance().addListener(
(String property, Object? value) => print(
'$property changed to $value in AppModel, listener would be triggered immediately right after setup '),
target: 'tasks',
immediate: true);
// Assignment would automatically trigger listeners
appStateModel.getInstance().token = "fe3f6b58-684e-4063-ba3b-1b8f14981a8e";
appStateModel.getInstance().baseUrl = "https://api.company.com";
appStateModel.getInstance().tasks = {"task-for-example": 45};
// 2. Boolean Signal Use Example
Signal isConsumerReady = Signal();
isConsumerReady.value = false;
// Register listener consumed immediately or awaited once via Signal(True).
isConsumerReady.promise(() => print("Task 1 executed"));
isConsumerReady.promise(() => print("Task 2 executed"));
// Release delayed signal
Future.delayed(Duration(seconds: 3), () => isConsumerReady.value = true);
// 3. DelayedLatch extends EnhancedLatchNotifier example
final GlobalFactory<DelayedLatch> latchDemo =
GlobalFactory(() => DelayedLatch());
latchDemo.getInstance().addListener((event) {
if (event.actionId == "test") {
print("triggered ==> ${event.actionId}, ${event.value}");
}
});
// Fire latch and cache state event
latchDemo.getInstance().fire(LatchStateEvent("test", 99));
// Listener triggered when unlatch called
Future.delayed(
const Duration(seconds: 3), () => latchDemo.getInstance().unlatch());
}