kaeru library

A reactive state management library for Flutter, inspired by Vue Composition API.

Classes

AsyncComputed<T>

A class that computes a value asynchronously and notifies listeners when the value changes.

Computed<T>

A reactive class that computes a value on demand and notifies listeners when the value changes.

KaeruBuilder

A widget that provides a KaeruMixin to its builder.

KaeruBuilderState

The state for a KaeruBuilder.

KaeruWidget<W extends StatefulWidget>

A widget that provides a reactive context for its children.

KaeruWidgetState<T extends StatefulWidget>

The state for a KaeruWidget.

LoadMoreController<T>

Manages the state and lifecycle of a "load more" request.

NullWidget

PaginationController<T>

Manages the state and lifecycle of a paginated request.

PaginationOptions<T>

Options for configuring the behavior of usePagination.

PaginationResult<T>

Represents the result of a paginated request.

Picker<T>

A class that memoizes a Computed value.

Prop<T>

Prop<T> is a wrapper that allows accessing and updating the value of a Ref<T>.

Ref<T>

A reactive container that holds a single value of type T and provides notifications whenever the value changes.

RequestController<T>

Manages the state and lifecycle of an asynchronous request.

RequestOptions<T>

Options for configuring the behavior of useRequest.

UseDark

A reactive utility to determine if the current theme is dark.

UseWidgetBox

A data class holding the reactive box constraints and the builder function.

UseWidgetSize

A data class holding the reactive size and the builder function.

Watch

A widget that automatically rebuilds when dependencies used inside its builder function change.

Mixins

KaeruLifeMixin<T extends StatefulWidget>

KaeruLifeMixin provides Vue-like lifecycle hooks for StatefulWidgets.

KaeruListenMixin<T extends StatefulWidget>

KaeruListenMixin provides a simple way to listen to ChangeNotifier updates within a StatefulWidget.

KaeruMixin<T extends StatefulWidget>

A mixin for State classes, providing helper methods to create reactive values and computations.

Extensions

ValueNotifierToRef on ValueNotifier<T>

An extension that allows converting a ValueNotifier to a Ref.

Functions

asyncComputed<T>(Future<T> compute()) → AsyncComputed<T>

Creates an instance of AsyncComputed with the given async function.

computed<T>(T compute()) → Computed<T>

Creates a reactive Computed with the provided getter function.

nextTick([VoidCallback? callback]) → Future<void>

Defers the execution of a callback until the next event loop iteration.

onActivated(VoidCallback callback) → void

Registers a callback to be called when the widget is activated.

onBeforeBuild(void callback(BuildContext context)) → void

Registers a callback to be called before the widget is built.

onBeforeUnmount(VoidCallback callback) → void

Registers a callback to be called before the widget is unmounted.

onDeactivated(VoidCallback callback) → void

Registers a callback to be called when the widget is deactivated.

onDebugFillProperties(void callback(DiagnosticPropertiesBuilder properties)) → void

Registers a callback to be called when the widget's properties are being filled for debugging.

onDependenciesChanged(VoidCallback callback) → void

Registers a callback to be called when the widget's dependencies change.

onMounted(VoidCallback callback) → void

Registers a callback to be called when the widget is first mounted.

onUpdated(void callback(StatefulWidget)) → void

Registers a callback to be called when the widget is updated.

onWatcherCleanup(VoidCallback callback) → void

Registers a cleanup function to be called when the watcher is disposed.

ref<T>(T initialValue) → Ref<T>

Creates a reactive Ref with the given initial value.

useAnimationController({TickerProvider? vsync, Duration? duration, String? debugLabel, double? lowerBound, double? upperBound, double? value, AnimationBehavior animationBehavior = AnimationBehavior.normal}) → AnimationController

Creates an AnimationController.

useContext() → BuildContext

Retrieves the current BuildContext from the KaeruWidget.

useDark() → Ref<bool>

A composable that returns a reactive boolean Ref indicating if the current theme is dark.

useFocusNode({String? debugLabel, bool canRequestFocus = true, FocusOnKeyEventCallback? onKeyEvent, bool skipTraversal = false}) → FocusNode

Creates a FocusNode.

useFocusScopeNode({String? debugLabel}) → FocusScopeNode

Creates a FocusScopeNode.

useKaeruContext() → KaeruMixin<StatefulWidget>?

Returns the current KaeruMixin instance.

useKeepAliveClient({bool wantKeepAlive = true}) → AutomaticKeepAliveClientMixin<StatefulWidget>

A hook that provides an AutomaticKeepAliveClientMixin for keeping a widget alive even when it is not visible.

useLifeContext() → KaeruLifeMixin<StatefulWidget>?

Returns the current KaeruLifeMixin instance.

useLoadMore<T>(Future<List<T>> service(int page, T? lastItem)) → LoadMoreController<T>

A composable for managing "load more" or infinite scrolling data fetching.

useNotifier<T extends ChangeNotifier>(T notifier) → T

Creates a ChangeNotifier.

useOverlayEntry(WidgetBuilder builder) → OverlayEntry

Creates an OverlayEntry.

usePageController({int initialPage = 0, bool keepPage = true, double viewportFraction = 1.0}) → PageController

Creates a PageController.

usePagination<T>(Future<PaginationResult<T>> service(int page, int pageSize), {PaginationOptions<T> options = const PaginationOptions()}) → PaginationController<T>

A composable for managing paginated data fetching.

usePick<T>(T selector()) → Picker<T>

Memoizes a Computed value and returns a Picker that can be used to access the value.

usePolling<T>(Future<T> service(), {Duration interval = const Duration(seconds: 5)}) → RequestController<T>

A composable for managing polling requests.

useRequest<T>(Future<T> service(), {RequestOptions<T> options = const RequestOptions()}) → RequestController<T>

A composable for managing asynchronous data fetching.

useRestoration({String? restorationId, required void restoreState(RestorationBucket? oldBucket, bool initialRestore), required void didToggleBucket(RestorationBucket? oldBucket), void registerForRestoration(RestorableProperty<Object?> property, String restorationId)?, void unregisterFromRestoration(RestorableProperty<Object?> property)?, VoidCallback? didUpdateRestorationId}) → RestorationMixin<StatefulWidget>

A hook that provides restoration capabilities for widgets.

useScrollController({double initialScrollOffset = 0.0, bool keepScrollOffset = true, String? debugLabel}) → ScrollController

Creates a ScrollController.

useSingleTickerState() → TickerProvider

Provides a hook to create a single ticker state for animations.

useStream<T>(Stream<T> stream) → Ref<T?>

Subscribes to a Stream and returns a Ref that is updated with the latest value from the stream.

useStreamController<T>({bool sync = false}) → StreamController<T>

Creates a StreamController.

useStreamDefault<T>(Stream<T> stream, {required T defaultValue}) → Ref<T>

Subscribes to a Stream and returns a Ref that is updated with the latest value from the stream.

useStreamSubscription<T>(Stream<T> stream, void onData(T event)?, {Function? onError, void onDone()?, bool? cancelOnError}) → StreamSubscription<T>

Creates a StreamSubscription.

useTabController({required int length, TickerProvider? vsync, int initialIndex = 0, Duration? animationDuration}) → TabController

Creates a TabController.

useTextEditingController([String? text]) → TextEditingController

Creates a TextEditingController.

useTheme() → ThemeData

A composable that returns the current ThemeData from the widget tree.

useTimer(Duration duration, void callback(), {bool periodic = false}) → Timer

Creates a Timer.

useTransformationController([Matrix4? value]) → TransformationController

Creates a TransformationController.

useValueNotifier<T>(T value) → ValueNotifier<T>

Creates a ValueNotifier.

useWidget<T extends Widget>() → T

A custom hook to retrieve the current widget of a specific type from the context.

useWidgetBox() → UseWidgetBox

A composable that provides the BoxConstraints of a widget reactively.

useWidgetSize() → UseWidgetSize

A composable that provides the Size of a widget reactively.

watch(Iterable<Listenable?> source, VoidCallback callback, {bool immediate = false}) → VoidCallback

Sets up a watcher on the given source and triggers the callback when any of the Listenable objects in the source change.

watch$(Iterable<Listenable?> source, VoidCallback callback, {bool immediate = false}) → VoidCallback

Sets up a watcher on the given source and triggers the callback when any of the Listenable objects in the source change. If immediate is true, the callback is triggered immediately after setting up the listener.

watchEffect(VoidCallback effect) → VoidCallback

Sets up a reactive effect triggered by callback.

watchEffect$(VoidCallback callback) → VoidCallback

Sets up a reactive effect triggered by callback and returns a function to dispose of the effect when it’s no longer needed.

Typedefs

Setup = Widget Function()

A function that returns a widget.

Exceptions / Errors

NoWatcherFoundException

An exception that is thrown when a reactive function is called outside of a reactive context.