useEvent returns a stable one-argument callable whose implementation is refreshed on every build. Use a record when the event needs multiple arguments.
Signature
StableEventCallback<T, R> useEvent<T, R>(R Function(T value) handler);
Lifecycle
final onValue = useEvent<int, void>((value) => save(value, currentUser));
Interactive useEvent demo
Multiplier 2 • result 0
The returned object's identity remains stable until unmount, while calls always reach the newest closure.
Server rendering
The callable is deterministic and usable on the server. It owns no browser resources.
Common mistakes
Do not call the handler during build when it mutates state. Use useCallback when dependency changes should deliberately change callback identity.
Related APIs
Use useLatest for a stable mutable reference and useEventListener for native DOM subscriptions.