async_field library Null safety

Async Field Library

Classes

AsyncField<T>
AsyncFieldID
AsyncLoop<I>
An async loop, similar to a for loop block.
AsyncSequenceLoop
An async sequence loop, from i to limit (exclusive).
AsyncStorage
A storage for AsyncField instances.
Completer<T>
A way to produce Future objects and to complete them later with a value or error.
DeferredLibrary
Indicates that loading of libraryName is deferred.
EventSink<T>
A Sink that supports adding errors.
Future<T>
The result of an asynchronous computation.
FutureOr<T>
A type representing values that are either Future<T> or T.
MultiStreamController<T>
An enhanced stream controller provided by Stream.multi.
Stream<T>
A source of asynchronous data events.
StreamConsumer<S>
Abstract interface for a "sink" accepting multiple entire streams.
StreamController<T>
A controller with the stream it controls.
StreamIterator<T>
An Iterator-like interface for the values of a Stream.
StreamSink<S>
A object that accepts stream events both synchronously and asynchronously.
StreamSubscription<T>
A subscription on events from a Stream.
StreamTransformer<S, T>
Transforms a Stream.
StreamTransformerBase<S, T>
Base class for implementing StreamTransformer.
StreamView<T>
Stream wrapper that only exposes the Stream interface.
SynchronousStreamController<T>
A stream controller that delivers its events synchronously.
Timer
A countdown timer that can be configured to fire once or repeatedly.
Zone
A zone represents an environment that remains stable across asynchronous calls.
ZoneDelegate
An adapted view of the parent zone.
ZoneSpecification
A parameter object with custom zone function handlers for Zone.fork.

Extensions

FutureDoubleExtension
FutureExtension
FutureExtensions
Convenience methods on futures.
FutureIntExtension
FutureNumExtension
FutureOrDoubleExtension
FutureOrExtension
Extension for FutureOr.
FutureOrIntExtension
FutureOrNumExtension
IterableFutureExtension
Extension for Iterable<Future<T>>.
IterableFutureOrExtension
Extension for Iterable<FutureOr<T>>.
IterableFutureOrExtensionNullable
Extensions that apply to iterables with a nullable element type.
MapFutureExtension
MapFutureKeyExtension
MapFutureValueExtension
MapFutureValueNullableExtension

Functions

asyncTry<R>(FutureOr<R?> tryBlock(), {FutureOr<R?> then(R? r)?, Function? onError, FutureOr<void> onFinally()?}) FutureOr<R?>
Executes a tryBlock in a try, then, catch and finally execution chain.
runZoned<R>(R body(), {Map<Object?, Object?>? zoneValues, ZoneSpecification? zoneSpecification, Function? onError}) → R
Runs body in its own zone.
runZonedGuarded<R>(R body(), void onError(Object error, StackTrace stack), {Map<Object?, Object?>? zoneValues, ZoneSpecification? zoneSpecification}) → R?
Runs body in its own error zone.
@Since("2.8")
scheduleMicrotask(void callback()) → void
Runs a function asynchronously.
unawaited(Future<void>? future) → void
Explicitly ignores a future.
@Since("2.15")

Typedefs

AsyncFieldDeleter<T> = FutureOr<bool> Function(AsyncField<T> asyncField)
AsyncFieldFetcher<T> = FutureOr<T> Function(AsyncField<T> asyncField)
AsyncFieldSaver<T> = FutureOr<T> Function(AsyncField<T> asyncField, T value)
ControllerCallback = void Function()
Type of a stream controller's onListen, onPause and onResume callbacks.
ControllerCancelCallback = FutureOr<void> Function()
Type of stream controller onCancel callbacks.
CreatePeriodicTimerHandler = Timer Function(Zone self, ZoneDelegate parent, Zone zone, Duration period, void f(Timer timer))
The type of a custom Zone.createPeriodicTimer implementation function.
CreateTimerHandler = Timer Function(Zone self, ZoneDelegate parent, Zone zone, Duration duration, void f())
The type of a custom Zone.createTimer implementation function.
ErrorCallbackHandler = AsyncError? Function(Zone self, ZoneDelegate parent, Zone zone, Object error, StackTrace? stackTrace)
The type of a custom Zone.errorCallback implementation function.
ForkHandler = Zone Function(Zone self, ZoneDelegate parent, Zone zone, ZoneSpecification? specification, Map<Object?, Object?>? zoneValues)
The type of a custom Zone.fork implementation function.
HandleUncaughtErrorHandler = void Function(Zone self, ZoneDelegate parent, Zone zone, Object error, StackTrace stackTrace)
The type of a custom Zone.handleUncaughtError implementation function.
PrintHandler = void Function(Zone self, ZoneDelegate parent, Zone zone, String line)
The type of a custom Zone.print implementation function.
RegisterBinaryCallbackHandler = ZoneBinaryCallback<R, T1, T2> Function<R, T1, T2>(Zone self, ZoneDelegate parent, Zone zone, R f(T1 arg1, T2 arg2))
The type of a custom Zone.registerBinaryCallback implementation function.
RegisterCallbackHandler = ZoneCallback<R> Function<R>(Zone self, ZoneDelegate parent, Zone zone, R f())
The type of a custom Zone.registerCallback implementation function.
RegisterUnaryCallbackHandler = ZoneUnaryCallback<R, T> Function<R, T>(Zone self, ZoneDelegate parent, Zone zone, R f(T arg))
The type of a custom Zone.registerUnaryCallback implementation function.
RunBinaryHandler = R Function<R, T1, T2>(Zone self, ZoneDelegate parent, Zone zone, R f(T1 arg1, T2 arg2), T1 arg1, T2 arg2)
The type of a custom Zone.runBinary implementation function.
RunHandler = R Function<R>(Zone self, ZoneDelegate parent, Zone zone, R f())
The type of a custom Zone.run implementation function.
RunUnaryHandler = R Function<R, T>(Zone self, ZoneDelegate parent, Zone zone, R f(T arg), T arg)
The type of a custom Zone.runUnary implementation function.
ScheduleMicrotaskHandler = void Function(Zone self, ZoneDelegate parent, Zone zone, void f())
The type of a custom Zone.scheduleMicrotask implementation function.
ZoneBinaryCallback<R, T1, T2> = R Function(T1 arg1, T2 arg2)
ZoneCallback<R> = R Function()
ZoneUnaryCallback<R, T> = R Function(T arg)

Exceptions / Errors

AsyncError
An error and a stack trace.
AsyncFieldError
DeferredLoadException
Thrown when a deferred library fails to load.
TimeoutException
Thrown when a scheduled timeout happens while waiting for an async result.