ValueListenableProvider<T>.value constructor
ValueListenableProvider<T>.value ({
- Key? key,
- required ValueListenable<
T> value, - UpdateShouldNotify<
T> ? updateShouldNotify, - Widget? child,
Listens to a ValueListenable and exposes its current value.
This is useful for testing purposes, to easily simular a provider update:
testWidgets('example', (tester) async {
// Create a ValueNotifier that tests will use to drive the application
final counter = ValueNotifier(0);
// Mount the application using ValueListenableProvider
await tester.pumpWidget(
ValueListenableProvider<int>.value(
value: counter,
child: MyApp(),
),
);
// Tests can now simulate a provider update by updating the notifier
// then calling tester.pump()
counter.value++;
await tester.pump();
});
Implementation
ValueListenableProvider.value({
Key? key,
required ValueListenable<T> value,
UpdateShouldNotify<T>? updateShouldNotify,
Widget? child,
}) : _valueListenable = value,
_updateShouldNotify = updateShouldNotify,
super(key: key, child: child);