ScrollableState class Null safety

State object for a Scrollable widget.

To manipulate a Scrollable widget's scroll position, use the object obtained from the position property.

To be informed of when a Scrollable widget is scrolling, use a NotificationListener to listen for ScrollNotification notifications.

This class is not intended to be subclassed. To specialize the behavior of a Scrollable, provide it with a ScrollPhysics.

Implemented types
Mixed in types




axisDirection AxisDirection
The direction in which the widget scrolls.
read-only, override
bucket RestorationBucket?
The RestorationBucket used for the restoration data of the RestorablePropertys registered to this mixin.
read-only, inherited
context BuildContext
The location in the tree where this widget builds.
read-only, inherited
hashCode int
The hash code for this object.
read-only, inherited
mounted bool
Whether this State object is currently in a tree.
read-only, inherited
notificationContext BuildContext?
The BuildContext that should be used when dispatching ScrollNotifications.
read-only, override
position ScrollPosition
The manager for this Scrollable widget's viewport position.
restorationId String?
The restoration ID used for the RestorationBucket in which the mixin will store the restoration data of all registered properties.
read-only, override
restorePending bool
Whether restoreState will be called at the beginning of the next build phase.
read-only, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
storageContext BuildContext
The BuildContext that should be used when searching for a PageStorage.
read-only, override
vsync TickerProvider
A TickerProvider to use when animating the scroll position.
read-only, override
widget Scrollable
The current configuration.
read-only, inherited


activate() → void
Called when this object is reinserted into the tree after having been removed via deactivate.
build(BuildContext context) Widget
Describes the part of the user interface represented by this widget.
createTicker(TickerCallback onTick) Ticker
Creates a ticker with the given callback.
deactivate() → void
Called when this object is removed from the tree.
@mustCallSuper, @protected, inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
didChangeDependencies() → void
Called when a dependency of this State object changes.
didToggleBucket(RestorationBucket? oldBucket) → void
Called when bucket switches between null and non-null values.
@mustCallSuper, @protected, inherited
didUpdateRestorationId() → void
Must be called when the value returned by restorationId changes.
@protected, inherited
didUpdateWidget(covariant Scrollable oldWidget) → void
Called whenever the widget configuration changes.
dispose() → void
Called when this object is removed from the tree permanently.
initState() → void
Called when this object is inserted into the tree.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
reassemble() → void
Called whenever the application is reassembled during debugging, for example during hot reload.
@mustCallSuper, @protected, inherited
registerForRestoration(RestorableProperty<Object?> property, String restorationId) → void
Registers a RestorableProperty for state restoration.
@protected, inherited
restoreState(RestorationBucket? oldBucket, bool initialRestore) → void
Called to initialize or restore the RestorablePropertys used by the State object.
saveOffset(double offset) → void
Called by the ScrollPosition whenever scrolling ends to persist the provided scroll offset for state restoration purposes.
setCanDrag(bool value) → void
Whether the user can drag the widget, for example to initiate a scroll.
@protected, override
setIgnorePointer(bool value) → void
Whether the contents of the widget should ignore PointerEvent inputs.
@protected, override
setSemanticsActions(Set<SemanticsAction> actions) → void
Set the SemanticsActions that should be expose to the semantics tree.
@protected, override
setState(VoidCallback fn) → void
Notify the framework that the internal state of this object has changed.
@protected, inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
toString({DiagnosticLevel minLevel =}) String
A string representation of this object.
toStringShort() String
A brief description of this object, usually just the runtimeType and the hashCode.
unregisterFromRestoration(RestorableProperty<Object?> property) → void
Unregisters a RestorableProperty from state restoration.
@protected, inherited


operator ==(Object other) bool
The equality operator.