widgets library

The Flutter widgets framework.

To use, importpackage:flutter/widgets.dart.

Classes

AbsorbPointer: A widget that absorbs pointers during hit testing.
AbstractLayoutBuilder<LayoutInfoType>: An abstract superclass for widgets that defer their building until layout.
Accumulator: Mutable wrapper of an integer that can be passed by reference to track avalue across a recursive stack.
Action<T extendsIntent>: Base class for an action or command to be performed.
ActionDispatcher: An action dispatcher that invokes the actions given to it.
ActionListener: A helper widget for making sure that listeners on an action are removed properly.
Actions: A widget that mapsIntents toActions to be used by its descendantswhen invoking anAction.
ActivateAction: AnAction that activates the currently focused control.
ActivateIntent: AnIntent that activates the currently focused control.
Align: A widget that aligns its child within itself and optionally sizes itselfbased on the child's size.
Alignment: A point within a rectangle.
AlignmentDirectional: An offset that's expressed as a fraction of aSize, but whose horizontalcomponent is dependent on the writing direction.
AlignmentGeometry: Base class forAlignment that allows for text-direction awareresolution.
AlignmentGeometryTween: An interpolation between twoAlignmentGeometry.
AlignmentTween: An interpolation between two alignments.
AlignTransition: Animated version of anAlign that animates itsAlign.alignment property.
AlwaysScrollableScrollPhysics: Scroll physics that always lets the user scroll.
AlwaysStoppedAnimation<T>: An animation that is always stopped at a given value.
AndroidView: Embeds an Android view in the Widget hierarchy.
AndroidViewSurface: Integrates an Android view with Flutter's compositor, touch, and semantics subsystems.
Animatable<T>: An object that can produce a value of typeT given anAnimation<double>as input.
AnimatedAlign: Animated version ofAlign which automatically transitions the child'sposition over a given duration whenever the givenalignment changes.
AnimatedBuilder: A general-purpose widget for building animations.
AnimatedContainer: Animated version ofContainer that gradually changes its values over a period of time.
AnimatedCrossFade: A widget that cross-fades between two given children and animates itselfbetween their sizes.
AnimatedDefaultTextStyle: Animated version ofDefaultTextStyle which automatically transitions thedefault text style (the text style to apply to descendantText widgetswithout explicit style) over a given duration whenever the given stylechanges.
AnimatedFractionallySizedBox: Animated version ofFractionallySizedBox which automatically transitions thechild's size over a given duration whenever the givenwidthFactor orheightFactor changes, as well as the position whenever the givenalignmentchanges.
AnimatedGrid: A scrolling container that animates items when they are inserted into or removed from a grid.in a grid.
AnimatedGridState: TheState for anAnimatedGrid that animates items when they areinserted or removed.
AnimatedList: A scrolling container that animates items when they are inserted or removed.
AnimatedListState: TheAnimatedListState forAnimatedList, a scrolling list container thatanimates items when they are inserted or removed.
AnimatedModalBarrier: A widget that prevents the user from interacting with widgets behind itself,and can be configured with an animated color value.
AnimatedOpacity: Animated version ofOpacity which automatically transitions the child'sopacity over a given duration whenever the given opacity changes.
AnimatedPadding: Animated version ofPadding which automatically transitions theindentation over a given duration whenever the given inset changes.
AnimatedPhysicalModel: Animated version ofPhysicalModel.
AnimatedPositioned: Animated version ofPositioned which automatically transitions the child'sposition over a given duration whenever the given position changes.
AnimatedPositionedDirectional: Animated version ofPositionedDirectional which automatically transitionsthe child's position over a given duration whenever the given positionchanges.
AnimatedRotation: Animated version ofTransform.rotate which automatically transitions the child'srotation over a given duration whenever the given rotation changes.
AnimatedScale: Animated version ofTransform.scale which automatically transitions the child'sscale over a given duration whenever the given scale changes.
AnimatedSize: Animated widget that automatically transitions its size over a givenduration whenever the given child's size changes.
AnimatedSlide: Widget which automatically transitions the child'soffset relative to its normal position whenever the given offset changes.
AnimatedSwitcher: A widget that by default does a cross-fade between a new widget and thewidget previously set on theAnimatedSwitcher as a child.
AnimatedWidget: A widget that rebuilds when the givenListenable changes value.
AnimatedWidgetBaseState<T extendsImplicitlyAnimatedWidget>: A base class for widgets with implicit animations that need to rebuild theirwidget tree as the animation runs.
Animation<T>: A value which might change over time, moving forward or backward.
AnimationController: A controller for an animation.
AnimationMax<T extendsnum>: An animation that tracks the maximum of two other animations.
AnimationMean: An animation ofdoubles that tracks the mean of two other animations.
AnimationMin<T extendsnum>: An animation that tracks the minimum of two other animations.
AnimationStyle: Used to override the default parameters of an animation.
AnnotatedRegion<T extendsObject>: Annotates a region of the layer tree with a value.
AppKitView: Widget that contains a macOS AppKit view.
AppLifecycleListener: A listener that can be used to listen to changes in the applicationlifecycle.
AspectRatio: A widget that attempts to size the child to a specific aspect ratio.
AssetBundle: A collection of resources used by the application.
AssetBundleImageKey: Key for the image obtained by anAssetImage orExactAssetImage.
AssetBundleImageProvider: A subclass ofImageProvider that knows aboutAssetBundles.
AssetImage: Fetches an image from anAssetBundle, having determined the exact image touse based on the context.
AsyncSnapshot<T>: Immutable representation of the most recent interaction with an asynchronouscomputation.
AutocompleteFirstOptionIntent: AnIntent to highlight the first option in the autocomplete list.
AutocompleteHighlightedOption: An inherited widget used to indicate which autocomplete option should behighlighted for keyboard navigation.
AutocompleteLastOptionIntent: AnIntent to highlight the last option in the autocomplete list.
AutocompleteNextOptionIntent: AnIntent to highlight the next option in the autocomplete list.
AutocompleteNextPageOptionIntent: AnIntent to highlight the option one page after the currently highlightedoption in the autocomplete list.
AutocompletePreviousOptionIntent: AnIntent to highlight the previous option in the autocomplete list.
AutocompletePreviousPageOptionIntent: AnIntent to highlight the option one page before the currentlyhighlighted option in the autocomplete list.
AutofillGroup: AnAutofillScope widget that groupsAutofillClients together.
AutofillGroupState: State associated with anAutofillGroup widget.
AutofillHints: A collection of commonly used autofill hint strings on different platforms.
AutomaticKeepAlive: Allows subtrees to request to be kept alive in lazy lists.
AutomaticNotchedShape: ANotchedShape created fromShapeBorders.
BackButtonDispatcher: Report to aRouter when the user taps the back button on platforms thatsupport back buttons (such as Android).
BackButtonListener: A convenience widget that registers a callback for when the back button is pressed.
BackdropFilter: A widget that applies a filter to the existing painted content and thenpaintschild.
BackdropGroup: A widget that establishes a shared backdrop layer for all childBackdropFilterwidgets that opt into using it.
BackdropKey: A backdrop key uniquely identifies the backdrop that aBackdropFilterLayersamples from.
BallisticScrollActivity: The activity a scroll view performs after being set into motion.
Banner: Displays a diagonal message above the corner of another widget.
BannerPainter: Paints aBanner.
Baseline: A widget that positions its child according to the child's baseline.
BeveledRectangleBorder: A rectangular border with flattened or "beveled" corners.
BlockSemantics: A widget that drops the semantics of all widget that were painted before itin the same semantic container.
Border: A border of a box, comprised of four sides: top, right, bottom, left.
BorderDirectional: A border of a box, comprised of four sides, the lateral sides of whichflip over based on the reading direction.
BorderRadius: An immutable set of radii for each corner of a rectangle.
BorderRadiusDirectional: An immutable set of radii for each corner of a rectangle, but with thecorners specified in a manner dependent on the writing direction.
BorderRadiusGeometry: Base class forBorderRadius that allows for text-direction aware resolution.
BorderRadiusTween: An interpolation between twoBorderRadiuss.
BorderSide: A side of a border of a box.
BorderTween: An interpolation between twoBorders.
BottomNavigationBarItem: An interactive button within either material'sBottomNavigationBaror the iOS themedCupertinoTabBar with an icon and title.
BouncingScrollPhysics: Scroll physics for environments that allow the scroll offset to go beyondthe bounds of the content, but then bounce the content back to the edge ofthose bounds.
BouncingScrollSimulation: An implementation of scroll physics that matches iOS.
BoxBorder: Base class for box borders that can paint as rectangles, circles, or roundedrectangles.
BoxConstraints: Immutable layout constraints forRenderBox layout.
BoxConstraintsTween: An interpolation between twoBoxConstraints.
BoxDecoration: An immutable description of how to paint a box.
BoxPainter: A stateful class that can paint a particularDecoration.
BoxScrollView: AScrollView that uses a single child layout model.
BoxShadow: A shadow cast by a box.
BuildContext: A handle to the location of a widget in the widget tree.
Builder: A stateless utility widget whosebuild method uses itsbuilder callback to create the widget's child.
BuildOwner: Manager class for the widgets framework.
BuildScope: A class that determines the scope of aBuildOwner.buildScope operation.
ButtonActivateIntent: AnIntent that activates the currently focused button.
CallbackAction<T extendsIntent>: AnAction that takes a callback in order to configure it without having tocreate an explicitAction subclass just to call a callback.
CallbackShortcuts: A widget that binds key combinations to specific callbacks.
Canvas: An interface for recording graphical operations.
CapturedThemes: Stores a list of capturedInheritedThemes that can be wrapped around achildWidget.
CatmullRomCurve: An animation easing curve that passes smoothly through the given controlpoints using a centripetal Catmull-Rom spline.
CatmullRomSpline: A 2D spline that passes smoothly through the given control points using acentripetal Catmull-Rom spline.
Center: A widget that centers its child within itself.
ChangeNotifier: A class that can be extended or mixed in that provides a change notificationAPI usingVoidCallback for notifications.
CharacterActivator: A shortcut combination that is triggered by a key event that produces aspecific character.
CharacterRange: A range of characters of aCharacters.
Characters: The characters of a string.
CheckedModeBanner: Displays aBanner saying "DEBUG" when running in debug mode.MaterialApp builds one of these by default.
ChildBackButtonDispatcher: A variant ofBackButtonDispatcher which listens to notifications from aparent back button dispatcher, and can take priority from its parent for thehandling of such notifications.
ChildVicinity: The relative position of a child in aTwoDimensionalViewport in relationto other children of the viewport.
CircleBorder: A border that fits a circle within the available space.
CircularNotchedRectangle: A rectangle with a smooth circular notch.
ClampingScrollPhysics: Scroll physics for environments that prevent the scroll offset from reachingbeyond the bounds of the content.
ClampingScrollSimulation: An implementation of scroll physics that aligns with Android.
ClipboardStatusNotifier: AValueNotifier whosevalue indicates whether the current contents ofthe clipboard can be pasted.
ClipContext: Clip utilities used byPaintingContext.
ClipOval: A widget that clips its child using an oval.
ClipPath: A widget that clips its child using a path.
ClipRect: A widget that clips its child using a rectangle.
ClipRRect: A widget that clips its child using a rounded rectangle.
ClipRSuperellipse: A widget that clips its child using a rounded superellipse.
Color: An immutable color value in ARGB format.
ColoredBox: A widget that paints its area with a specifiedColor and then draws itschild on top of that color.
ColorFilter: A description of a color filter to apply when drawing a shape or compositinga layer with a particularPaint. A color filter is a function that takestwo colors, and outputs one color. When applied during compositing, it isindependently applied to each pixel of the layer being drawn before theentire layer is merged with the destination.
ColorFiltered: Applies aColorFilter to its child.
ColorProperty: DiagnosticsProperty that has anColor as value.
ColorSwatch<T>: A color that has a small table of related colors called a "swatch".
ColorTween: An interpolation between two colors.
Column: A widget that displays its children in a vertical array.
ComponentElement: AnElement that composes otherElements.
CompositedTransformFollower: A widget that follows aCompositedTransformTarget.
CompositedTransformTarget: A widget that can be targeted by aCompositedTransformFollower.
CompoundAnimation<T>: An interface for combining multiple Animations. Subclasses need onlyimplement thevalue getter to control how the child animations arecombined. Can be chained to combine more than 2 animations.
ConstantTween<T>: A tween with a constant value.
ConstrainedBox: A widget that imposes additional constraints on its child.
ConstrainedLayoutBuilder<ConstraintType extendsConstraints>: A specializedAbstractLayoutBuilder whose widget subtree depends on theincomingConstraintType that will be imposed on the widget.
ConstraintsTransformBox: A container widget that applies an arbitrary transform to its constraints,and sizes its child using the resultingBoxConstraints, optionallyclipping, or treating the overflow as an error.
Container: A convenience widget that combines common painting, positioning, and sizingwidgets.
ContentInsertionConfiguration: Configures the ability to insert media content through the soft keyboard.
ContextAction<T extendsIntent>: An abstractAction subclass that adds an optionalBuildContext to theisEnabled andinvoke methods to be able to provide context to actions.
ContextMenuButtonItem: The type and callback for a context menu button.
ContextMenuController: Builds and manages a context menu at a given location.
ContinuousRectangleBorder: A rectangular border with smooth continuous transitions between the straightsides and the rounded corners.
CopySelectionTextIntent: AnIntent that represents a user interaction that attempts to copy or cutthe current selection in the field.
Cubic: A cubic polynomial mapping of the unit interval.
Curve: An parametric animation easing curve, i.e. a mapping of the unit interval tothe unit interval.
Curve2D: Abstract class that defines an API for evaluating 2D parametric curves.
Curve2DSample: A class that holds a sample of a 2D parametric curve, containing thevalue(the X, Y coordinates) of the curve at the parametric valuet.
CurvedAnimation: An animation that applies a curve to another animation.
Curves: A collection of common animation curves.
CurveTween: Transforms the value of the given animation by the given curve.
CustomClipper<T>: An interface for providing custom clips.
CustomMultiChildLayout: A widget that uses a delegate to size and position multiple children.
CustomPaint: A widget that provides a canvas on which to draw during the paint phase.
CustomPainter: The interface used byCustomPaint (in the widgets library) andRenderCustomPaint (in the rendering library).
CustomPainterSemantics: Contains properties describing information drawn in a rectangle contained bytheCanvas used by aCustomPaint.
CustomScrollView: AScrollView that creates custom scroll effects usingslivers.
CustomSingleChildLayout: A widget that defers the layout of its single child to a delegate.
DebugCreator: A wrapper class for theElement that is the creator of aRenderObject.
DecoratedBox: A widget that paints aDecoration either before or after its child paints.
DecoratedBoxTransition: Animated version of aDecoratedBox that animates the different propertiesof itsDecoration.
DecoratedSliver: A sliver widget that paints aDecoration either before or after its childpaints.
Decoration: A description of a box decoration (a decoration applied to aRect).
DecorationImage: An image for a box decoration.
DecorationImagePainter: The painter for aDecorationImage.
DecorationTween: An interpolation between twoDecorations.
DefaultAssetBundle: A widget that determines the default asset bundle for its descendants.
DefaultPlatformMenuDelegate: The platform menu delegate that handles the built-in macOS platform menugeneration using the 'flutter/menu' channel.
DefaultSelectionStyle: The selection style to apply to descendantEditableText widgets whichdon't have an explicit style.
DefaultTextEditingShortcuts: A widget with the shortcuts used for the default text editing behavior.
DefaultTextHeightBehavior: TheTextHeightBehavior that will apply to descendantText andEditableTextwidgets which have not explicitly setText.textHeightBehavior.
DefaultTextStyle: The text style to apply to descendantText widgets which don't have anexplicit style.
DefaultTextStyleTransition: Animated version of aDefaultTextStyle that animates the different propertiesof itsTextStyle.
DefaultTransitionDelegate<T>: The default implementation ofTransitionDelegate that theNavigator willuse if itsNavigator.transitionDelegate is not specified.
DefaultWidgetsLocalizations: US English localizations for the widgets library.
DeleteCharacterIntent: Deletes the character before or after the caret location, based on whetherforward is true.
DeleteToLineBreakIntent: Deletes from the current caret location to the previous or next soft or hardline break, based on whetherforward is true.
DeleteToNextWordBoundaryIntent: Deletes from the current caret location to the previous or next wordboundary, based on whetherforward is true.
DesktopTextSelectionToolbarLayoutDelegate: Positions the toolbar atanchor if it fits, otherwise moves it so that itjust fits fully on-screen.
DevToolsDeepLinkProperty: Debugging message for DevTools deep links.
DiagnosticsNode: Defines diagnostics data for avalue.
DirectionalCaretMovementIntent: ADirectionalTextEditingIntent that moves the caret or the selection to anew location.
DirectionalFocusAction: AnAction that moves the focus to the focusable node in the directionconfigured by the associatedDirectionalFocusIntent.direction.
DirectionalFocusIntent: AnIntent that represents moving to the next focusable node in the givendirection.
Directionality: A widget that determines the ambient directionality of text andtext-direction-sensitive render objects.
DirectionalTextEditingIntent: A text editing relatedIntent that performs an operation towards a givendirection of the current caret location.
DisableWidgetInspectorScope: Disables the Flutter DevTools Widget Inspector for aWidget subtree.
DismissAction: AnAction that dismisses the focused widget.
Dismissible: A widget that can be dismissed by dragging in the indicateddirection.
DismissIntent: AnIntent that dismisses the currently focused widget.
DismissMenuAction: An action that closes all the menus associated with the givenMenuController.
DismissUpdateDetails: Details forDismissUpdateCallback.
DisplayFeatureSubScreen: Positionschild such that it avoids overlapping anyDisplayFeature thatsplits the screen into sub-screens.
DisposableBuildContext<T extendsState<StatefulWidget>>: Provides non-leaking access to aBuildContext.
DoNothingAction: AnAction that doesn't perform any action when invoked.
DoNothingAndStopPropagationIntent: AnIntent that is bound to aDoNothingAction, but, in addition to notperforming an action, also stops the propagation of the key event bound tothis intent to other key event handlers in the focus chain.
DoNothingAndStopPropagationTextIntent: AnIntent to send the event straight to the engine.
DoNothingIntent: AnIntent that is bound to aDoNothingAction.
DragBoundary: Provides aDragBoundaryDelegate for its descendants whose bounds are those defined by this widget.
DragBoundaryDelegate<T>: The interface for defining the algorithm for a boundary that a specified shape is dragged within.
DragDownDetails: Details object for callbacks that useGestureDragDownCallback.
DragEndDetails: Details object for callbacks that useGestureDragEndCallback.
Draggable<T extendsObject>: A widget that can be dragged from to aDragTarget.
DraggableDetails: Represents the details when a specific pointer event occurred ontheDraggable.
DraggableScrollableActuator: A widget that can notify a descendentDraggableScrollableSheet that itshould reset its position to the initial state.
DraggableScrollableController: Controls aDraggableScrollableSheet.
DraggableScrollableNotification: ANotification related to the extent, which is the size, and scrolloffset, which is the position of the child list, of theDraggableScrollableSheet.
DraggableScrollableSheet: A container for aScrollable that responds to drag gestures by resizingthe scrollable until a limit is reached, and then scrolling.
DragScrollActivity: The activity a scroll view performs when the user drags their fingeracross the screen.
DragStartDetails: Details object for callbacks that useGestureDragStartCallback.
DragTarget<T extendsObject>: A widget that receives data when aDraggable widget is dropped.
DragTargetDetails<T>: Represents the details when a pointer event occurred on theDragTarget.
DragUpdateDetails: Details object for callbacks that useGestureDragUpdateCallback.
DrivenScrollActivity: An activity that drives a scroll view through a given animation.
DualTransitionBuilder: A transition builder that animates itschild based on theAnimationStatus of the providedanimation.
EdgeDraggingAutoScroller: An auto scroller that scrolls thescrollable if a drag gesture drags closeto its edge.
EdgeInsets: An immutable set of offsets in each of the four cardinal directions.
EdgeInsetsDirectional: An immutable set of offsets in each of the four cardinal directions, butwhose horizontal components are dependent on the writing direction.
EdgeInsetsGeometry: Base class forEdgeInsets that allows for text-direction awareresolution.
EdgeInsetsGeometryTween: An interpolation between twoEdgeInsetsGeometrys.
EdgeInsetsTween: An interpolation between twoEdgeInsetss.
EditableText: A basic text input field.
EditableTextState: State for anEditableText.
EditableTextTapOutsideIntent: AnIntent that represents a tap outside the field.
EditableTextTapUpOutsideIntent: AnIntent that represents a tap outside the field.
ElasticInCurve: An oscillating curve that grows in magnitude while overshooting its bounds.
ElasticInOutCurve: An oscillating curve that grows and then shrinks in magnitude whileovershooting its bounds.
ElasticOutCurve: An oscillating curve that shrinks in magnitude while overshooting its bounds.
Element: An instantiation of aWidget at a particular location in the tree.
EmptyTextSelectionControls: Text selection controls that do not show any toolbars or handles.
EnableWidgetInspectorScope: Enables the Flutter DevTools Widget Inspector for aWidget subtree.
ErrorDescription: An explanation of the problem and its cause, any information that may helptrack down the problem, background information, etc.
ErrorHint: AnErrorHint provides specific, non-obvious advice that may be applicable.
ErrorSummary: A short (one line) description of the problem that was detected.
ErrorWidget: A widget that renders an exception's message.
ExactAssetImage: Fetches an image from anAssetBundle, associating it with the given scale.
ExcludeFocus: A widget that controls whether or not the descendants of this widget arefocusable.
ExcludeFocusTraversal: A widget that controls whether or not the descendants of this widget aretraversable.
ExcludeSemantics: A widget that drops all the semantics of its descendants.
Expanded: A widget that expands a child of aRow,Column, orFlexso that the child fills the available space.
ExpandSelectionToDocumentBoundaryIntent: Expands the current selection to the document boundary in the directiongiven byforward.
ExpandSelectionToLineBreakIntent: Expands the current selection to the closest line break in the directiongiven byforward.
Expansible: AStatefulWidget that expands and collapses.
ExpansibleController: A controller for managing the expansion state of anExpansible.
ExtendSelectionByCharacterIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the previous or the next characterboundary.
ExtendSelectionByPageIntent: Scrolls up or down by page depending on theforward parameter.Extends the selection up or down by page based on theforward parameter.
ExtendSelectionToDocumentBoundaryIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the start or the end of the document.
ExtendSelectionToLineBreakIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the closest line break in the directiongiven byforward.
ExtendSelectionToNextParagraphBoundaryIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the previous or the next paragraphboundary.
ExtendSelectionToNextParagraphBoundaryOrCaretLocationIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the previous or the next paragraphboundary depending on theforward parameter.
ExtendSelectionToNextWordBoundaryIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the previous or the next wordboundary.
ExtendSelectionToNextWordBoundaryOrCaretLocationIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the previous or the next wordboundary, or theTextSelection.base position if it's closer in the movedirection.
ExtendSelectionVerticallyToAdjacentLineIntent: Extends, or moves the current selection from the currentTextSelection.extent position to the closest position on the adjacentline.
ExtendSelectionVerticallyToAdjacentPageIntent: Expands, or moves the current selection from the currentTextSelection.extent position to the closest position on the adjacentpage.
FadeInImage: An image that shows aplaceholder image while the targetimage isloading, then fades in the new image when it loads.
FadeTransition: Animates the opacity of a widget.
Feedback: Provides platform-specific acoustic and/or haptic feedback for certainactions.
FileImage: Decodes the givenFile object as an image, associating it with the givenscale.
FittedBox: Scales and positions its child within itself according tofit.
FittedSizes: The pair of sizes returned byapplyBoxFit.
FixedColumnWidth: Sizes the column to a specific number of pixels.
FixedExtentMetrics: Metrics for aScrollPosition to a scroll view with fixed item sizes.
FixedExtentScrollController: A controller for scroll views whose items have the same size.
FixedExtentScrollPhysics: A snapping physics that always lands directly on items instead of anywherewithin the scroll extent.
FixedScrollMetrics: An immutable snapshot of values associated with aScrollable viewport.
Flex: A widget that displays its children in a one-dimensional array.
FlexColumnWidth: Sizes the column by taking a part of the remaining space once allthe other columns have been laid out.
Flexible: A widget that controls how a child of aRow,Column, orFlex flexes.
FlippedCurve: A curve that is the reversed inversion of its given curve.
FlippedTweenSequence: Enables creating a flippedAnimation whose value is defined by a sequenceofTweens.
Flow: A widget that sizes and positions children efficiently, according to thelogic in aFlowDelegate.
FlowDelegate: A delegate that controls the appearance of a flow layout.
FlowPaintingContext: A context in which aFlowDelegate paints.
FlutterErrorDetails: Class for information provided toFlutterExceptionHandler callbacks.
FlutterLogo: The Flutter logo, in widget form. This widget respects theIconTheme.For guidelines on using the Flutter logo, visithttps://flutter.dev/brand.
FlutterLogoDecoration: An immutable description of how to paint Flutter's logo.
Focus: A widget that manages aFocusNode to allow keyboard focus to be givento this widget and its descendants.
FocusableActionDetector: A widget that combines the functionality ofActions,Shortcuts,MouseRegion and aFocus widget to create a detector that defines actionsand key bindings, and provides callbacks for handling focus and hoverhighlights.
FocusAttachment: An attachment point for aFocusNode.
FocusManager: Manages the focus tree.
FocusNode: An object that can be used by a stateful widget to obtain the keyboard focusand to handle keyboard events.
FocusOrder: Base class for all sort orders forOrderedTraversalPolicy traversal.
FocusScope: AFocusScope is similar to aFocus, but also serves as a scope for itsdescendants, restricting focus traversal to the scoped controls.
FocusScopeNode: A subclass ofFocusNode that acts as a scope for its descendants,maintaining information about which descendant is currently or was lastfocused.
FocusTraversalGroup: A widget that describes the inherited focus policy for focus traversal forits descendants, grouping them into a separate traversal group.
FocusTraversalOrder: An inherited widget that describes the order in which its child subtreeshould be traversed.
FocusTraversalPolicy: Determines how focusable widgets are traversed within aFocusTraversalGroup.
FontFeature: A feature tag and value that affect the selection of glyphs in a font.
FontVariation: An axis tag and value that can be used to customize variable fonts.
FontWeight: The thickness of the glyphs used to draw the text.
ForcePressDetails: Details object for callbacks that useGestureForcePressStartCallback,GestureForcePressPeakCallback,GestureForcePressEndCallback orGestureForcePressUpdateCallback.
Form: An optional container for grouping together multiple form field widgets(e.g.TextField widgets).
FormField<T>: A single form field.
FormFieldState<T>: The current state of aFormField. Passed to theFormFieldBuilder methodfor use in constructing the form field's widget.
FormState: State associated with aForm widget.
FractionallySizedBox: A widget that sizes its child to a fraction of the total available space.For more details about the layout algorithm, seeRenderFractionallySizedOverflowBox.
FractionalOffset: An offset that's expressed as a fraction of aSize.
FractionalOffsetTween: An interpolation between two fractional offsets.
FractionalTranslation: Applies a translation transformation before painting its child.
FractionColumnWidth: Sizes the column to a fraction of the table's constraints' maxWidth.
FutureBuilder<T>: A widget that builds itself based on the latest snapshot of interaction withaFuture.
GestureDetector: A widget that detects gestures.
GestureRecognizerFactory<T extendsGestureRecognizer>: Factory for creating gesture recognizers.
GestureRecognizerFactoryWithHandlers<T extendsGestureRecognizer>: Factory for creating gesture recognizers that delegates to callbacks.
GlobalKey<T extendsState<StatefulWidget>>: A key that is unique across the entire app.
GlobalObjectKey<T extendsState<StatefulWidget>>: A global key that takes its identity from the object used as its value.
GlowingOverscrollIndicator: A visual indication that a scroll view has overscrolled.
GlyphInfo: The measurements of a character (or a sequence of visually connectedcharacters) within a paragraph.
Gradient: A 2D gradient.
GradientRotation: AGradientTransform that rotates the gradient around the center-point ofits bounding box.
GradientTransform: Base class for transforming gradient shaders without applying the sametransform to the entire canvas.
GridPaper: A widget that draws a rectilinear grid of lines one pixel wide.
GridView: A scrollable, 2D array of widgets.
Hero: A widget that marks its child as being a candidate forhero animations.
HeroController: ANavigator observer that managesHero transitions.
HeroControllerScope: An inherited widget to host a hero controller.
HeroMode: Enables or disablesHeroes in the widget subtree.
HoldScrollActivity: A scroll activity that does nothing but can be released to resumenormal idle behavior.
HSLColor: A color represented usingalpha,hue,saturation, andlightness.
HSVColor: A color represented usingalpha,hue,saturation, andvalue.
HtmlElementView: Embeds an HTML element in the Widget hierarchy in Flutter web.
Icon: A graphical icon widget drawn with a glyph from a font described inanIconData such as material's predefinedIconDatas inIcons.
IconData: A description of an icon fulfilled by a font glyph.
IconDataProperty: DiagnosticsProperty that has anIconData as value.
IconTheme: Controls the default properties of icons in a widget subtree.
IconThemeData: Defines the size, font variations, color, opacity, and shadows of icons.
IdleScrollActivity: A scroll activity that does nothing.
IgnoreBaseline: A widget that causes the parent to ignore thechild for the purposesof baseline alignment.
IgnorePointer: A widget that is invisible during hit testing.
Image: A widget that displays an image.
ImageCache: Class for caching images.
ImageCacheStatus: Information about how theImageCache is tracking an image.
ImageChunkEvent: An immutable notification of image bytes that have been incrementally loaded.
ImageConfiguration: Configuration information passed to theImageProvider.resolve method toselect a specific image.
ImageFiltered: Applies anImageFilter to its child.
ImageIcon: An icon that comes from anImageProvider, e.g. anAssetImage.
ImageInfo: Adart:ui.Image object with its corresponding scale.
ImageProvider<T extendsObject>: Identifies an image without committing to the precise final asset. Thisallows a set of images to be identified and for the precise image to laterbe resolved based on the environment, e.g. the device pixel ratio.
ImageShader: A shader (as used byPaint.shader) that tiles an image.
ImageSizeInfo: Tracks the bytes used by adart:ui.Image compared to the bytes needed topaint that image without scaling it.
ImageStream: A handle to an image resource.
ImageStreamCompleter: Base class for those that manage the loading ofdart:ui.Image objects forImageStreams.
ImageStreamCompleterHandle: An opaque handle that keeps anImageStreamCompleter alive even if it haslost its last listener.
ImageStreamListener: Interface for receiving notifications about the loading of an image.
ImplicitlyAnimatedWidget: An abstract class for building widgets that animate changes to theirproperties.
ImplicitlyAnimatedWidgetState<T extendsImplicitlyAnimatedWidget>: A base class for theState of widgets with implicit animations.
IndexedSemantics: A widget that annotates the child semantics with an index.
IndexedSlot<T extendsElement?>: A value forElement.slot used for children ofMultiChildRenderObjectElements.
IndexedStack: AStack that shows a single child from a list of children.
InheritedElement: AnElement that uses anInheritedWidget as its configuration.
InheritedModel<T>: AnInheritedWidget that's intended to be used as the base class for modelswhose dependents may only depend on one part or "aspect" of the overallmodel.
InheritedModelElement<T>: AnElement that uses aInheritedModel as its configuration.
InheritedNotifier<T extendsListenable>: An inherited widget for aListenable notifier, which updates itsdependencies when thenotifier is triggered.
InheritedTheme: AnInheritedWidget that defines visual properties like colorsand text styles, which thechild's subtree depends on.
InheritedWidget: Base class for widgets that efficiently propagate information down the tree.
InlineSpan: An immutable span of inline content which forms part of a paragraph.
InlineSpanSemanticsInformation: The textual and semantic label information for anInlineSpan.
InspectorButton: An abstract base class for creating Material or Cupertino-styled inspectorbuttons.
InspectorReferenceData: Structure to help reference count Dart objects referenced by a GUI toolusingWidgetInspectorService.
InspectorSelection: Mutable selection state of the inspector.
InspectorSerializationDelegate: A delegate that configures how a hierarchy ofDiagnosticsNodes areserialized by the Flutter Inspector.
Intent: An abstract class representing a particular configuration of anAction.
InteractiveViewer: A widget that enables pan and zoom interactions with its child.
Interval: A curve that is 0.0 untilbegin, then curved (according tocurve) from0.0 atbegin to 1.0 atend, then remains 1.0 pastend.
IntrinsicColumnWidth: Sizes the column according to the intrinsic dimensions of all thecells in that column.
IntrinsicHeight: A widget that sizes its child to the child's intrinsic height.
IntrinsicWidth: A widget that sizes its child to the child's maximum intrinsic width.
IntTween: An interpolation between two integers that rounds.
IOSSystemContextMenuItem: Describes a context menu button that will be rendered in the iOS systemcontext menu and not by Flutter itself.
IOSSystemContextMenuItemCopy: Creates an instance ofIOSSystemContextMenuItem for the system's built-incopy button.
IOSSystemContextMenuItemCustom: Creates an instance ofIOSSystemContextMenuItem for custom action buttonsdefined by the developer.
IOSSystemContextMenuItemCut: Creates an instance ofIOSSystemContextMenuItem for the system's built-incut button.
IOSSystemContextMenuItemLiveText: Creates an instance ofIOSSystemContextMenuItem for thesystem's built-in Live Text button.
IOSSystemContextMenuItemLookUp: Creates an instance ofIOSSystemContextMenuItem for thesystem's built-in look up button.
IOSSystemContextMenuItemPaste: Creates an instance ofIOSSystemContextMenuItem for the system's built-inpaste button.
IOSSystemContextMenuItemSearchWeb: Creates an instance ofIOSSystemContextMenuItem for thesystem's built-in search web button.
IOSSystemContextMenuItemSelectAll: Creates an instance ofIOSSystemContextMenuItem for the system's built-inselect all button.
IOSSystemContextMenuItemShare: Creates an instance ofIOSSystemContextMenuItem for thesystem's built-in share button.
KeepAlive: Mark a child as needing to stay alive even when it's in a lazy list thatwould otherwise remove it.
KeepAliveHandle: AListenable which can be manually triggered.
KeepAliveNotification: Indicates that the subtree through which this notification bubbles must bekept alive even if it would normally be discarded as an optimization.
Key: AKey is an identifier forWidgets,Elements andSemanticsNodes.
KeyboardInsertedContent: A class representing rich content (such as a PNG image) inserted via thesystem input method.
KeyboardListener: A widget that calls a callback whenever the user presses or releases a keyon a keyboard.
KeyedSubtree: A widget that builds its child.
KeyEvent: Defines the interface for keyboard key events.
KeySet<T extendsKeyboardKey>: A set ofKeyboardKeys that can be used as the keys in aMap.
LabeledGlobalKey<T extendsState<StatefulWidget>>: A global key with a debugging label.
LayerLink: An object that aLeaderLayer can register with.
LayoutBuilder: Builds a widget tree that can depend on the parent widget's size.
LayoutChangedNotification: Indicates that the layout of one of the descendants of the object receivingthis notification has changed in some way, and that therefore anyassumptions about that layout are no longer valid.
LayoutId: Metadata for identifying children in aCustomMultiChildLayout.
LeafRenderObjectElement: AnElement that uses aLeafRenderObjectWidget as its configuration.
LeafRenderObjectWidget: A superclass forRenderObjectWidgets that configureRenderObject subclassesthat have no children.
LexicalFocusOrder: Can be given to aFocusTraversalOrder widget to use a String to assign alexical order to a widget subtree that is using aOrderedTraversalPolicy to define the order in which widgets should betraversed with the keyboard.
LimitedBox: A box that limits its size only when it's unconstrained.
LinearBorder: AnOutlinedBorder likeBoxBorder that allows one to define a rectangular (box) borderin terms of zero to fourLinearBorderEdges, each of which is rendered as a single line.
LinearBorderEdge: Defines the relative size and alignment of oneLinearBorder edge.
LinearGradient: A 2D linear gradient.
LineMetrics: LineMetrics stores the measurements and statistics of a single line in theparagraph.
ListBody: A widget that arranges its children sequentially along a given axis, forcingthem to the dimension of the parent in the other axis.
Listenable: An object that maintains a list of listeners.
ListenableBuilder: A general-purpose widget for building a widget subtree when aListenablechanges.
Listener: A widget that calls callbacks in response to common pointer events.
ListView: A scrollable list of widgets arranged linearly.
ListWheelChildBuilderDelegate: A delegate that supplies children forListWheelScrollView using a buildercallback.
ListWheelChildDelegate: A delegate that supplies children forListWheelScrollView.
ListWheelChildListDelegate: A delegate that supplies children forListWheelScrollView using anexplicit list.
ListWheelChildLoopingListDelegate: A delegate that supplies infinite children forListWheelScrollView bylooping an explicit list.
ListWheelElement: Element that supports building children lazily forListWheelViewport.
ListWheelScrollView: A box in which children on a wheel can be scrolled.
ListWheelViewport: A viewport showing a subset of children on a wheel.
LiveTextInputStatusNotifier: AValueNotifier whosevalue indicates whether the current device supports the Live Text(OCR) function.
Locale: An identifier used to select a user's language and formatting preferences.
LocalHistoryEntry: An entry in the history of aLocalHistoryRoute.
Localizations: Defines theLocale for itschild and the localized resources that thechild depends on.
LocalizationsDelegate<T>: A factory for a set of localized resources of typeT, to be loaded by aLocalizations widget.
LocalizationsResolver: A helper class used to manage localization resolution.
LocalKey: A key that is not aGlobalKey.
LogicalKeySet: A set ofLogicalKeyboardKeys that can be used as the keys in a map.
LongPressDraggable<T extendsObject>: Makes its child draggable starting from long press.
LongPressEndDetails: Details for callbacks that useGestureLongPressEndCallback.
LongPressMoveUpdateDetails: Details for callbacks that useGestureLongPressMoveUpdateCallback.
LongPressStartDetails: Details for callbacks that useGestureLongPressStartCallback.
LookupBoundary: A lookup boundary controls what entities are visible to descendants of theboundary via the static lookup methods provided by the boundary.
MagnifierController: A controller for a magnifier.
MagnifierDecoration: The decorations to put around the loupe in aRawMagnifier.
MagnifierInfo: A data class that contains the geometry information of text layoutsand selection gestures, used to position magnifiers.
MaskFilter: A mask filter to apply to shapes as they are painted. A mask filter is afunction that takes a bitmap of color pixels, and returns another bitmap ofcolor pixels.
Matrix4: 4D Matrix.Values are stored in column major order.
Matrix4Tween: An interpolation between twoMatrix4s.
MatrixTransition: Animates theMatrix4 of a transformed widget.
MatrixUtils: Utility functions for working with matrices.
MaxColumnWidth: Sizes the column such that it is the size that is the maximum oftwo column width specifications.
MediaQuery: Establishes a subtree in which media queries resolve to the given data.
MediaQueryData: Information about a piece of media (e.g., a window).
MemoryImage: Decodes the givenUint8List buffer as an image, associating it with thegiven scale.
MenuController: A controller used to manage a menu created by a subclass ofRawMenuAnchor,such asMenuAnchor,MenuBar,SubmenuButton.
MergeSemantics: A widget that merges the semantics of its descendants.
MetaData: Holds opaque meta data in the render tree.
MinColumnWidth: Sizes the column such that it is the size that is the minimum oftwo column width specifications.
ModalBarrier: A widget that prevents the user from interacting with widgets behind itself.
ModalRoute<T>: A route that blocks interaction with previous routes.
MouseCursor: An interface for mouse cursor definitions.
MouseRegion: A widget that tracks the movement of mice.
MultiChildLayoutDelegate: A delegate that controls the layout of multiple children.
MultiChildRenderObjectElement: AnElement that uses aMultiChildRenderObjectWidget as its configuration.
MultiChildRenderObjectWidget: A superclass forRenderObjectWidgets that configureRenderObject subclassesthat have a single list of children. (This superclass only provides thestorage for that child list, it doesn't actually provide the updatinglogic.)
MultiFrameImageStreamCompleter: Manages the decoding and scheduling of image frames.
MultiSelectableSelectionContainerDelegate: A delegate that handles events and updates for multipleSelectablechildren.
NavigationNotification: A notification that a change in navigation has taken place.
NavigationToolbar: NavigationToolbar is a layout helper to position 3 widgets or groups ofwidgets along a horizontal axis that's sensible for an application'snavigation bar such as in Material Design and in iOS.
Navigator: A widget that manages a set of child widgets with a stack discipline.
NavigatorObserver: An interface for observing the behavior of aNavigator.
NavigatorPopHandler<T>: Enables the handling of system back gestures.
NavigatorState: The state for aNavigator widget.
NestedScrollView: A scrolling view inside of which can be nested other scrolling views, withtheir scroll positions being intrinsically linked.
NestedScrollViewState: TheState for aNestedScrollView.
NestedScrollViewViewport: TheViewport variant used byNestedScrollView.
NetworkImage: Fetches the given URL from the network, associating it with the given scale.
NeverScrollableScrollPhysics: Scroll physics that does not allow the user to scroll.
NextFocusAction: AnAction that moves the focus to the next focusable node in the focusorder.
NextFocusIntent: AnIntent bound toNextFocusAction, which moves the focus to the nextfocusable node in the focus traversal order.
NotchedShape: A shape with a notch in its outline.
Notification: A notification that can bubble up the widget tree.
NotificationListener<T extendsNotification>: A widget that listens forNotifications bubbling up the tree.
NumericFocusOrder: Can be given to aFocusTraversalOrder widget to assign a numerical orderto a widget subtree that is using aOrderedTraversalPolicy to define theorder in which widgets should be traversed with the keyboard.
ObjectKey: A key that takes its identity from the object used as its value.
Offset: An immutable 2D floating-point offset.
Offstage: A widget that lays the child out as if it was in the tree, but withoutpainting anything, without making the child available for hit testing, andwithout taking any room in the parent.
OneFrameImageStreamCompleter: Manages the loading ofdart:ui.Image objects for staticImageStreams (thosewith only one frame).
Opacity: A widget that makes its child partially transparent.
OrderedTraversalPolicy: AFocusTraversalPolicy that orders nodes by an explicit order that residesin the nearestFocusTraversalOrder widget ancestor.
OrientationBuilder: Builds a widget tree that can depend on the parent widget's orientation(distinct from the device orientation).
OutlinedBorder: A ShapeBorder that draws an outline with the width and color specifiedbyside.
OvalBorder: A border that fits an elliptical shape.
OverflowBar: A widget that lays out itschildren in a row unless they"overflow" the available horizontal space, in which case it laysthem out in a column instead.
OverflowBox: A widget that imposes different constraints on its child than it getsfrom its parent, possibly allowing the child to overflow the parent.
Overlay: A stack of entries that can be managed independently.
OverlayEntry: A place in anOverlay that can contain a widget.
OverlayPortal: A widget that renders its overlay child on anOverlay.
OverlayPortalController: A class to show, hide and bring to top anOverlayPortal's overlay childin the targetOverlay.
OverlayRoute<T>: A route that displays widgets in theNavigator'sOverlay.
OverlayState: The current state of anOverlay.
OverscrollIndicatorNotification: A notification that either aGlowingOverscrollIndicator or aStretchingOverscrollIndicator will start showing an overscroll indication.
OverscrollNotification: A notification that aScrollable widget has not changed its scroll positionbecause the change would have caused its scroll position to go outside ofits scroll bounds.
Padding: A widget that insets its child by the given padding.
Page<T>: Describes the configuration of aRoute.
PageController: A controller forPageView.
PageMetrics: Metrics for aPageView.
PageRoute<T>: A modal route that replaces the entire screen.
PageRouteBuilder<T>: A utility class for defining one-off page routes in terms of callbacks.
PageScrollPhysics: Scroll physics used by aPageView.
PageStorage: Establish a subtree in which widgets can opt into persisting states afterbeing destroyed.
PageStorageBucket: A storage bucket associated with a page in an app.
PageStorageKey<T>: AKey that can be used to persist the widget state in storage after thedestruction and will be restored when recreated.
PageTransitionsBuilder: Defines a page transition animation for aPageRoute.
PageView: A scrollable list that works page by page.
Paint: A description of the style to use when drawing on aCanvas.
PaintingContext: A place to paint.
ParametricCurve<T>: An abstract class providing an interface for evaluating a parametric curve.
ParentDataElement<T extendsParentData>: AnElement that uses aParentDataWidget as its configuration.
ParentDataWidget<T extendsParentData>: Base class for widgets that hookParentData information to children ofRenderObjectWidgets.
PasteTextIntent: AnIntent to paste text fromClipboard to the field.
Path: A complex, one-dimensional subset of a plane.
PerformanceOverlay: Displays performance statistics.
PhysicalModel: A widget representing a physical layer that clips its children to a shape.
PhysicalShape: A widget representing a physical layer that clips its children to a path.
PinnedHeaderSliver: A sliver that keeps its Widget child at the top of the aCustomScrollView.
Placeholder: A widget that draws a box that represents where other widgets will one daybe added.
PlaceholderDimensions: Holds theSize and baseline required to represent the dimensions ofa placeholder in text.
PlaceholderSpan: An immutable placeholder that is embedded inline within text.
PlatformMenu: A class for representing menu items that have child submenus.
PlatformMenuBar: A menu bar that uses the platform's native APIs to construct and render amenu described by aPlatformMenu/PlatformMenuItem hierarchy.
PlatformMenuDelegate: An abstract delegate class that can be used to setWidgetsBinding.platformMenuDelegate to provide for managing platformmenus.
PlatformMenuItem: A class forPlatformMenuItems that do not have submenus (as aPlatformMenuwould), but can be selected.
PlatformMenuItemGroup: A class that groups other menu items into sections delineated by dividers.
PlatformProvidedMenuItem: A class that represents a menu item that is provided by the platform.
PlatformRouteInformationProvider: The route information provider that propagates the platform route information changes.
PlatformSelectableRegionContextMenu: A widget that provides native selection context menu for its child subtree.
PlatformViewCreationParams: The parameters used to create aPlatformViewController.
PlatformViewLink: Links a platform view with the Flutter framework.
PlatformViewSurface: Integrates a platform view with Flutter's compositor, touch, and semantics subsystems.
PointerCancelEvent: The input from the pointer is no longer directed towards this receiver.
PointerDownEvent: The pointer has made contact with the device.
PointerEvent: Base class for touch, stylus, or mouse events.
PointerMoveEvent: The pointer has moved with respect to the device while the pointer is incontact with the device.
PointerUpEvent: The pointer has stopped making contact with the device.
PopEntry<T>: Allows listening to and preventing pops.
PopScope<T>: Manages back navigation gestures.
PopupRoute<T>: A modal route that overlays a widget over the current route.
Positioned: A widget that controls where a child of aStack is positioned.
PositionedDirectional: A widget that controls where a child of aStack is positioned withoutcommitting to a specificTextDirection.
PositionedTransition: Animated version ofPositioned which takes a specificAnimation<RelativeRect> to transition the child's position from a startposition to an end position over the lifetime of the animation.
PredictiveBackRoute: An interface for a route that supports predictive back gestures.
PreferredSize: A widget with a preferred size.
PreferredSizeWidget: An interface for widgets that can return the size this widget would preferif it were otherwise unconstrained.
PreviousFocusAction: AnAction that moves the focus to the previous focusable node in the focusorder.
PreviousFocusIntent: AnIntent bound toPreviousFocusAction, which moves the focus to theprevious focusable node in the focus traversal order.
PrimaryScrollController: Associates aScrollController with a subtree.
PrioritizedAction: AnAction that iterates through a list ofIntents, invoking the firstthat is enabled.
PrioritizedIntents: AnIntent that evaluates a series of specifiedorderedIntents forexecution.
ProxyAnimation: An animation that is a proxy for another animation.
ProxyElement: AnElement that uses aProxyWidget as its configuration.
ProxyWidget: A widget that has a child widget provided to it, instead of building a newwidget.
RadialGradient: A 2D radial gradient.
RadioGroup<T>: A group for radios.
RadioGroupRegistry<T>: An abstract interface for registering a group of radios.
Radius: A radius for either circular or elliptical shapes.
RangeMaintainingScrollPhysics: Scroll physics that attempt to keep the scroll position in range when thecontents change dimensions suddenly.
RawAutocomplete<T extendsObject>: A widget for helping the user make a selection by entering some text andchoosing from among a list of options.
RawDialogRoute<T>: A general dialog route which allows for customization of the dialog popup.
RawGestureDetector: A widget that detects gestures described by the given gesturefactories.
RawGestureDetectorState: State for aRawGestureDetector.
RawImage: A widget that displays adart:ui.Image directly.
RawKeyboardListener: A widget that calls a callback whenever the user presses or releases a keyon a keyboard.
RawKeyEvent: Defines the interface for raw key events.
RawMagnifier: A common base class for magnifiers.
RawMenuAnchor: A widget that wraps a child and anchors a floating menu.
RawMenuAnchorGroup: Creates a menu anchor that is always visible and is not displayed in anOverlayPortal.
RawMenuOverlayInfo: Anchor and menu information passed toRawMenuAnchor.
RawRadio<T>: A Radio button that provides basic radio functionalities.
RawScrollbar: An extendable base class for building scrollbars that fade in and out.
RawScrollbarState<T extendsRawScrollbar>: The state for aRawScrollbar widget, also shared by theScrollbar andCupertinoScrollbar widgets.
RawView: The lower level workhorse widget forView that bootstraps a render treefor a view.
ReadingOrderTraversalPolicy: Traverses the focus order in "reading order".
Rect: An immutable, 2D, axis-aligned, floating-point rectangle whose coordinatesare relative to a given origin.
RectTween: An interpolation between two rectangles.
RedoTextIntent: AnIntent that represents a user interaction that attempts to go back tothe previous editing state.
RelativePositionedTransition: Animated version ofPositioned which transitions the child's positionbased on the value ofrect relative to a bounding box with thespecifiedsize.
RelativeRect: An immutable 2D, axis-aligned, floating-point rectangle whose coordinatesare given relative to another rectangle's edges, known as the container.Since the dimensions of the rectangle are relative to those of thecontainer, this class has no width and height members. To determine thewidth or height of the rectangle, convert it to aRect usingtoRect()(passing the container's own Rect), and then examine that object.
RelativeRectTween: An interpolation between two relative rects.
RenderBox: A render object in a 2D Cartesian coordinate system.
RenderNestedScrollViewViewport: TheRenderViewport variant used byNestedScrollView.
RenderObject: An object in the render tree.
RenderObjectElement: AnElement that uses aRenderObjectWidget as its configuration.
RenderObjectToWidgetAdapter<T extendsRenderObject>: A bridge from aRenderObject to anElement tree.
RenderObjectToWidgetElement<T extendsRenderObject>: The root of an element tree that is hosted by aRenderObject.
RenderObjectWidget: RenderObjectWidgets provide the configuration forRenderObjectElements,which wrapRenderObjects, which provide the actual rendering of theapplication.
RenderSemanticsGestureHandler: Listens for the specified gestures from the semantics server (e.g.an accessibility tool).
RenderSliverOverlapAbsorber: A sliver that wraps another, forcing its layout extent to be treated asoverlap.
RenderSliverOverlapInjector: A sliver that has a sliver geometry based on the values stored in aSliverOverlapAbsorberHandle.
RenderTapRegion: A render object that defines a region that can detect taps inside or outsideof itself and any group of regions it belongs to, without participating inthegesturedisambiguation system.
RenderTapRegionSurface: A render object that provides notification of a tap inside or outside of aset of registered regions, without participating in thegesturedisambiguation system(other than to consume tap down events ifTapRegion.consumeOutsideTaps istrue).
RenderTreeRootElement: ARenderObjectElement used to manage the root of a render tree.
RenderTwoDimensionalViewport: A base class for viewing render objects that scroll in two dimensions.
ReorderableDelayedDragStartListener: A wrapper widget that will recognize the start of a drag operation bylooking for a long press event. Once it is recognized, it will starta drag operation on the wrapped item in the reorderable list.
ReorderableDragStartListener: A wrapper widget that will recognize the start of a drag on the wrappedwidget by aPointerDownEvent, and immediately initiate dragging thewrapped item to a new location in a reorderable list.
ReorderableList: A scrolling container that allows the user to interactively reorder thelist items.
ReorderableListState: The state for a list that allows the user to interactively reorderthe list items.
RepaintBoundary: A widget that creates a separate display list for its child.
ReplaceTextIntent: AnIntent that represents a user interaction that attempts to modify thecurrentTextEditingValue in an input field.
RequestFocusAction: AnAction that requests the focus on the node it is given in itsRequestFocusIntent.
RequestFocusIntent: An intent for use with theRequestFocusAction, which supplies theFocusNode that should be focused.
ResizeImage: Instructs Flutter to decode the image at the specified dimensionsinstead of at its native size.
ResizeImageKey: Key used internally byResizeImage.
RestorableBool: ARestorableProperty that knows how to store and restore abool.
RestorableBoolN: ARestorableProperty that knows how to store and restore abool that isnullable.
RestorableChangeNotifier<T extendsChangeNotifier>: A base class for creating aRestorableProperty that stores and restores aChangeNotifier.
RestorableDateTime: ARestorableValue that knows how to save and restoreDateTime.
RestorableDateTimeN: ARestorableValue that knows how to save and restoreDateTime that isnullable.
RestorableDouble: ARestorableProperty that knows how to store and restore adouble.
RestorableDoubleN: ARestorableProperty that knows how to store and restore adoublethat is nullable.
RestorableEnum<T extendsEnum>: ARestorableProperty that knows how to store and restore anEnumtype.
RestorableEnumN<T extendsEnum>: ARestorableProperty that knows how to store and restore a nullableEnumtype.
RestorableInt: ARestorableProperty that knows how to store and restore anint.
RestorableIntN: ARestorableProperty that knows how to store and restore anintthat is nullable.
RestorableListenable<T extendsListenable>: A base class for creating aRestorableProperty that stores and restores aListenable.
RestorableNum<T extendsnum>: ARestorableProperty that knows how to store and restore anum.
RestorableNumN<T extendsnum?>: ARestorableProperty that knows how to store and restore anumthat is nullable.
RestorableProperty<T>: Manages an object of typeT, whose value aState object wants to haverestored during state restoration.
RestorableRouteFuture<T>: Gives access to aRoute object and its return value that was added to anavigator via one of its "restorable" API methods.
RestorableString: ARestorableProperty that knows how to store and restore aString.
RestorableStringN: ARestorableProperty that knows how to store and restore aStringthat is nullable.
RestorableTextEditingController: ARestorableProperty that knows how to store and restore aTextEditingController.
RestorableValue<T>: ARestorableProperty that makes the wrapped value accessible to the owningState object via thevalue getter and setter.
RestorationBucket: ARestorationBucket holds pieces of the restoration data that a part ofthe application needs to restore its state.
RestorationScope: Creates a new scope for restoration IDs used by descendant widgets to claimRestorationBuckets.
ReverseAnimation: An animation that is the reverse of another animation.
ReverseTween<T extendsObject?>: ATween that evaluates itsparent in reverse.
RichText: A paragraph of rich text.
RootBackButtonDispatcher: The default implementation of back button dispatcher for the root router.
RootElement: The root of the element tree.
RootRenderObjectElement: Deprecated. Unused in the framework and will be removed in a future versionof Flutter.
RootRestorationScope: Inserts a child bucket ofRestorationManager.rootBucket into the widgettree and makes it available to descendants viaRestorationScope.of.
RootWidget: A widget for the root of the widget tree.
RotatedBox: A widget that rotates its child by a integral number of quarter turns.
RotationTransition: Animates the rotation of a widget.
RoundedRectangleBorder: A rectangular border with rounded corners.
RoundedSuperellipseBorder: A rectangular border with rounded corners following the shape of anRSuperellipse.
Route<T>: An abstraction for an entry managed by aNavigator.
RouteAware: An interface for objects that are aware of their currentRoute.
RouteInformation: A piece of routing information.
RouteInformationParser<T>: A delegate that is used by theRouter widget to parse a route informationinto a configuration of type T.
RouteInformationProvider: A route information provider that provides route information for theRouter widget
RouteObserver<R extendsRoute>: ANavigator observer that notifiesRouteAwares of changes to thestate of theirRoute.
Router<T>: The dispatcher for opening and closing pages of an application.
RouterConfig<T>: A convenient bundle to configure aRouter widget.
RouterDelegate<T>: A delegate that is used by theRouter widget to build and configure anavigating widget.
RouteSettings: Data that might be useful in constructing aRoute.
RouteTransitionRecord: ARoute wrapper interface that can be staged forTransitionDelegate todecide how its underlyingRoute should transition on or off screen.
Row: A widget that displays its children in a horizontal array.
RRect: An immutable rounded rectangle with the custom radii for all four corners.
RSTransform: A transform consisting of a translation, a rotation, and a uniform scale.
RSuperellipse: An immutable rounded superellipse.
SafeArea: A widget that insets its child with sufficient padding to avoid intrusionsby the operating system.
SawTooth: A sawtooth curve that repeats a given number of times over the unit interval.
ScaleEndDetails: Details forGestureScaleEndCallback.
ScaleStartDetails: Details forGestureScaleStartCallback.
ScaleTransition: Animates the scale of a transformed widget.
ScaleUpdateDetails: Details forGestureScaleUpdateCallback.
Scrollable: A widget that manages scrolling in one dimension and informs theViewportthrough which the content is viewed.
ScrollableDetails: Describes the aspects of a Scrollable widget to inform inherited widgetslikeScrollBehavior for decorating or enumerate the properties of combinedScrollables, such asTwoDimensionalScrollable.
ScrollableState: State object for aScrollable widget.
ScrollAction: AnAction that scrolls the relevantScrollable by the amount configuredin theScrollIntent given to it.
ScrollActivity: Base class for scrolling activities like dragging and flinging.
ScrollActivityDelegate: A backend for aScrollActivity.
ScrollAwareImageProvider<T extendsObject>: AnImageProvider that makes use ofScrollable.recommendDeferredLoadingForContext to avoid loading images whenrapidly scrolling.
ScrollbarPainter: Paints a scrollbar's track and thumb.
ScrollBehavior: Describes howScrollable widgets should behave.
ScrollConfiguration: Controls howScrollable widgets behave in a subtree.
ScrollContext: An interface thatScrollable widgets implement in order to useScrollPosition.
ScrollController: Controls a scrollable widget.
ScrollDragController: Scrolls a scroll view as the user drags their finger across the screen.
ScrollEndNotification: A notification that aScrollable widget has stopped scrolling.
ScrollHoldController: Interface for holding aScrollable stationary.
ScrollIncrementDetails: A details object that describes the type of scroll increment being requestedof aScrollIncrementCalculator function, as well as the current metricsfor the scrollable.
ScrollIntent: AnIntent that represents scrolling the nearest scrollable by an amountappropriate for thetype specified.
ScrollMetricsNotification: A notification that a scrollable widget'sScrollMetrics have changed.
ScrollNotification: ANotification related to scrolling.
ScrollNotificationObserver: Notifies its listeners when a descendant scrolls.
ScrollNotificationObserverState: The listener list state for aScrollNotificationObserver returned byScrollNotificationObserver.of.
ScrollPhysics: Determines the physics of aScrollable widget.
ScrollPosition: Determines which portion of the content is visible in a scroll view.
ScrollPositionWithSingleContext: A scroll position that manages scroll activities for a singleScrollContext.
ScrollSpringSimulation: ASpringSimulation where the value ofx is guaranteed to have exactly theend value when the simulationisDone.
ScrollStartNotification: A notification that aScrollable widget has started scrolling.
ScrollToDocumentBoundaryIntent: Scrolls to the beginning or end of the document depending on theforwardparameter.
ScrollUpdateNotification: A notification that aScrollable widget has changed its scroll position.
ScrollView: A widget that combines aScrollable and aViewport to create aninteractive scrolling pane of content in one dimension.
SelectableRegion: A widget that introduces an area for user selections.
SelectableRegionSelectionStatusScope: Notifies its listeners when the selection under aSelectableRegion orSelectionArea is being changed or finalized.
SelectableRegionState: State for aSelectableRegion.
SelectAction: An action that selects the currently focused control.
SelectAllTextIntent: AnIntent to select everything in the field.
SelectIntent: AnIntent that selects the currently focused control.
SelectionContainer: A container that handlesSelectionEvents for theSelectables inthe subtree.
SelectionContainerDelegate: A delegate to handleSelectionEvents for aSelectionContainer.
SelectionDetails: A read-only interface for accessing the details of a selection under aSelectionListener.
SelectionListener: ASelectionContainer that allows the user to access theSelectionDetails andlisten to selection changes for the child subtree it wraps under aSelectionAreaorSelectableRegion.
SelectionListenerNotifier: Notifies listeners when the selection under aSelectionListener has beenchanged.
SelectionOverlay: An object that manages a pair of selection handles and a toolbar.
SelectionRegistrarScope: An inherited widget to host aSelectionRegistrar for the subtree.
Semantics: A widget that annotates the widget tree with a description of the meaning ofthe widgets.
SemanticsDebugger: A widget that visualizes the semantics for the child.
SemanticsGestureDelegate: A base class that describes what semantics notations aRawGestureDetectorshould add to the render objectRenderSemanticsGestureHandler.
SensitiveContent: Widget to set theContentSensitivity of content in the widgettree.
SensitiveContentHost: Host of the current content sensitivity for the widget tree that containssome numberSensitiveContent widgets.
Shader: Base class for objects such asGradient andImageShader whichcorrespond to shaders as used byPaint.shader.
ShaderMask: A widget that applies a mask generated by aShader to its child.
ShaderWarmUp: Interface for drawing an image to warm up Skia shader compilations.
Shadow: A single shadow.
ShapeBorder: Base class for shape outlines.
ShapeBorderClipper: ACustomClipper that clips to the outer path of aShapeBorder.
ShapeDecoration: An immutable description of how to paint an arbitrary shape.
SharedAppData: Enables sharing key/value data with itschild and all of thechild's descendants.
ShortcutActivator: An interface to define the keyboard key combination to trigger a shortcut.
ShortcutManager: A manager of keyboard shortcut bindings used byShortcuts to handle keyevents.
ShortcutMapProperty: ADiagnosticsProperty which handles formatting aMap<LogicalKeySet, Intent>(the same type as theShortcuts.shortcuts property) so that itsdiagnostic output is human-readable.
ShortcutRegistrar: A widget that holds aShortcutRegistry which allows descendants to add,remove, or replace shortcuts.
ShortcutRegistry: A class used byShortcutRegistrar that allows adding or removing shortcutbindings by descendants of theShortcutRegistrar.
ShortcutRegistryEntry: A entry returned byShortcutRegistry.addAll that allows the caller toidentify the shortcuts they registered with theShortcutRegistry throughtheShortcutRegistrar.
Shortcuts: A widget that creates key bindings to specific actions for itsdescendants.
ShortcutSerialization: A class used byMenuSerializableShortcut to describe the shortcut forserialization to send to the platform for rendering aPlatformMenuBar.
ShrinkWrappingViewport: A widget that is bigger on the inside and shrink wraps its children in themain axis.
Simulation: The base class for all simulations.
SingleActivator: A shortcut key combination of a single key and modifiers.
SingleChildLayoutDelegate: A delegate for computing the layout of a render object with a single child.
SingleChildRenderObjectElement: AnElement that uses aSingleChildRenderObjectWidget as its configuration.
SingleChildRenderObjectWidget: A superclass forRenderObjectWidgets that configureRenderObject subclassesthat have a single child slot.
SingleChildScrollView: A box in which a single widget can be scrolled.
Size: Holds a 2D floating-point size.
SizeChangedLayoutNotification: Indicates that the size of one of the descendants of the object receivingthis notification has changed, and that therefore any assumptions about thatlayout are no longer valid.
SizeChangedLayoutNotifier: A widget that automatically dispatches aSizeChangedLayoutNotificationwhen the layout dimensions of its child change.
SizedBox: A box with a specified size.
SizedOverflowBox: A widget that is a specific size but passes its original constraintsthrough to its child, which may then overflow.
SizeTransition: Animates its own size and clips and aligns its child.
SizeTween: An interpolation between two sizes.
SlideTransition: Animates the position of a widget relative to its normal position.
SliverAnimatedGrid: ASliverGrid that animates items when they are inserted or removed.
SliverAnimatedGridState: The state for aSliverAnimatedGrid that animates items when they areinserted or removed.
SliverAnimatedList: ASliverList that animates items when they are inserted or removed.
SliverAnimatedListState: The state for aSliverAnimatedList that animates items when they areinserted or removed.
SliverAnimatedOpacity: Animated version ofSliverOpacity which automatically transitions thesliver child's opacity over a given duration whenever the given opacitychanges.
SliverChildBuilderDelegate: A delegate that supplies children for slivers using a builder callback.
SliverChildDelegate: A delegate that supplies children for slivers.
SliverChildListDelegate: A delegate that supplies children for slivers using an explicit list.
SliverConstrainedCrossAxis: A sliver that constrains the cross axis extent of its sliver child.
SliverCrossAxisExpanded: Set a flex factor for allocating space in the cross axis direction.
SliverCrossAxisGroup: A sliver that places multiple sliver children in a linear array alongthe cross axis.
SliverEnsureSemantics: A sliver that ensures its sliver child is included in the semantics tree.
SliverFadeTransition: Animates the opacity of a sliver widget.
SliverFillRemaining: A sliver that contains a single box child that fills the remaining space inthe viewport.
SliverFillViewport: A sliver that contains multiple box children that each fills the viewport.
SliverFixedExtentList: A sliver that places multiple box children with the same main axis extent ina linear array.
SliverFloatingHeader: A sliver that shows itschild when the user scrolls forward and hides itwhen the user scrolls backwards.
SliverGrid: A sliver that places multiple box children in a two dimensional arrangement.
SliverGridDelegate: Controls the layout of tiles in a grid.
SliverGridDelegateWithFixedCrossAxisCount: Creates grid layouts with a fixed number of tiles in the cross axis.
SliverGridDelegateWithMaxCrossAxisExtent: Creates grid layouts with tiles that each have a maximum cross-axis extent.
SliverIgnorePointer: A sliver widget that is invisible during hit testing.
SliverLayoutBuilder: Builds a sliver widget tree that can depend on its ownSliverConstraints.
SliverList: A sliver that places multiple box children in a linear array along the mainaxis.
SliverMainAxisGroup: A sliver that places multiple sliver children in a linear array alongthe main axis, one after another.
SliverMultiBoxAdaptorElement: An element that lazily builds children for aSliverMultiBoxAdaptorWidget.
SliverMultiBoxAdaptorWidget: A base class for slivers that have multiple box children.
SliverOffstage: A sliver that lays its sliver child out as if it was in the tree, butwithout painting anything, without making the sliver child available for hittesting, and without taking any room in the parent.
SliverOpacity: A sliver widget that makes its sliver child partially transparent.
SliverOverlapAbsorber: A sliver that wraps another, forcing its layout extent to be treated asoverlap.
SliverOverlapAbsorberHandle: Handle to provide to aSliverOverlapAbsorber, aSliverOverlapInjector,and anNestedScrollViewViewport, to shift overlap in aNestedScrollView.
SliverOverlapInjector: A sliver that has a sliver geometry based on the values stored in aSliverOverlapAbsorberHandle.
SliverPadding: A sliver that applies padding on each side of another sliver.
SliverPersistentHeader: A sliver whose size varies when the sliver is scrolled to the edgeof the viewport opposite the sliver'sGrowthDirection.
SliverPersistentHeaderDelegate: Delegate for configuring aSliverPersistentHeader.
SliverPrototypeExtentList: A sliver that places its box children in a linear array and constrains themto have the same extent as a prototype item along the main axis.
SliverReorderableList: A sliver list that allows the user to interactively reorder the list items.
SliverReorderableListState: The state for a sliver list that allows the user to interactively reorderthe list items.
SliverResizingHeader: A sliver that is pinned to the start of itsCustomScrollView andreacts to scrolling by resizing between the intrinsic sizes of itsmin and max extent prototypes.
SliverSafeArea: A sliver that insets another sliver by sufficient padding to avoidintrusions by the operating system.
SliverSemantics: A sliver that annotates its subtree with a description of the meaning ofthe slivers.
SliverToBoxAdapter: A sliver that contains a single box widget.
SliverVariedExtentList: A sliver that places its box children in a linear array and constrains themto have the corresponding extent returned byitemExtentBuilder.
SliverVisibility: Whether to show or hide a sliver child.
SliverWithKeepAliveWidget: A base class for slivers that haveKeepAlive children.
SlottedMultiChildRenderObjectWidget<SlotType,ChildType extendsRenderObject>: A superclass forRenderObjectWidgets that configureRenderObjectsubclasses that organize their children in different slots.
SlottedRenderObjectElement<SlotType,ChildType extendsRenderObject>: Element used by theSlottedMultiChildRenderObjectWidget.
SnapshotController: A controller for theSnapshotWidget that controls when the child image is displayedand when to regenerated the child image.
SnapshotPainter: A painter used to paint either a snapshot or the child widgets thatwould be a snapshot.
SnapshotWidget: A widget that can replace its child with a snapshotted version of the child.
Spacer: Spacer creates an adjustable, empty spacer that can be used to tune thespacing between widgets in aFlex container, likeRow orColumn.
SpellCheckConfiguration: Controls how spell check is performed for text input.
Split: A curve that progresses according tobeginCurve untilsplit, thenaccording toendCurve.
SpringDescription: Structure that describes a spring's constants.
Stack: A widget that positions its children relative to the edges of its box.
StadiumBorder: A border that fits a stadium-shaped border (a box with semicircles on the ends)within the rectangle of the widget it is applied to.
StarBorder: A border that fits a star or polygon-shaped border within the rectangle ofthe widget it is applied to.
State<T extendsStatefulWidget>: The logic and internal state for aStatefulWidget.
StatefulBuilder: A platonic widget that both has state and calls a closure to obtain its child widget.
StatefulElement: AnElement that uses aStatefulWidget as its configuration.
StatefulWidget: A widget that has mutable state.
StatelessElement: AnElement that uses aStatelessWidget as its configuration.
StatelessWidget: A widget that does not require mutable state.
StaticSelectionContainerDelegate: A delegate that manages updating multipleSelectable children where theSelectables do not change or move around frequently.
StatusTransitionWidget: A widget that rebuilds when the given animation changes status.
StepTween: An interpolation between two integers that floors.
StreamBuilder<T>: Widget that builds itself based on the latest snapshot of interaction withaStream.
StreamBuilderBase<T,S>: Base class for widgets that build themselves based on interaction witha specifiedStream.
StretchEffect: A widget that applies a stretching visual effect to its child.
StretchingOverscrollIndicator: A Material Design visual indication that a scroll view has overscrolled.
StrutStyle: Defines the strut, which sets the minimum height a line can berelative to the baseline.
SweepGradient: A 2D sweep gradient.
SystemContextMenu: Displays the system context menu on top of the Flutter view.
SystemMouseCursors: A collection of systemMouseCursors.
SystemTextScaler: ATextScaler that reflects the user's font scale preferences from theplatform's accessibility settings.
Table: A widget that uses the table layout algorithm for its children.
TableBorder: Border specification forTable widgets.
TableCell: A widget that controls how a child of aTable is aligned.
TableColumnWidth: Base class to describe how wide a column in aRenderTable should be.
TableRow: A horizontal group of cells in aTable.
TapDownDetails: Details forGestureTapDownCallback, such as position.
TapRegion: A widget that defines a region that can detect taps inside or outside ofitself and any group of regions it belongs to, without participating in thegesturedisambiguation system(other than to consume tap down events ifconsumeOutsideTaps is true).
TapRegionRegistry: An interface for registering and unregistering aRenderTapRegion(typically created with aTapRegion widget) with aRenderTapRegionSurface (typically created with aTapRegionSurfacewidget).
TapRegionSurface: A widget that provides notification of a tap inside or outside of a set ofregistered regions, without participating in thegesturedisambiguationsystem.
TapUpDetails: Details forGestureTapUpCallback, such as position.
Text: A run of text with a single style.
TextAlignVertical: The vertical alignment of text within an input box.
TextBox: A rectangle enclosing a run of text.
TextDecoration: A linear decoration to draw near the text.
TextEditingController: A controller for an editable text field.
TextEditingValue: The current text, selection, and composing state for editing a run of text.
TextFieldTapRegion: ATapRegion that adds its children to the tap region group for widgetsbased on theEditableText text editing widget, such asTextField andCupertinoTextField.
TextHeightBehavior: Defines how to applyTextStyle.height over and under text.
TextInputType: The type of information for which to optimize the text input control.
TextMagnifierConfiguration: A configuration object for a magnifier (e.g. in a text field).
TextPainter: An object that paints aTextSpan tree into aCanvas.
TextPosition: A position in a string of text.
TextRange: A range of characters in a string of text.
TextScaler: A class that describes how textual contents should be scaled for betterreadability.
TextSelection: A range of text that represents a selection.
TextSelectionControls: An interface for building the selection UI, to be provided by theimplementer of the toolbar widget.
TextSelectionGestureDetector: A gesture detector to respond to non-exclusive event chains for a text field.
TextSelectionGestureDetectorBuilder: Builds aTextSelectionGestureDetector to wrap anEditableText.
TextSelectionGestureDetectorBuilderDelegate: Delegate interface for theTextSelectionGestureDetectorBuilder.
TextSelectionOverlay: An object that manages a pair of text selection handles for aRenderEditable.
TextSelectionPoint: Represents the coordinates of the point in a selection, and the textdirection at that point, relative to top left of theRenderEditable thatholds the selection.
TextSelectionToolbarAnchors: The position information for a text selection toolbar.
TextSelectionToolbarLayoutDelegate: ASingleChildLayoutDelegate for use withCustomSingleChildLayout thatpositions its child aboveanchorAbove if it fits, or otherwise belowanchorBelow.
TextSpan: An immutable span of text.
TextStyle: An immutable style describing how to format and paint text.
TextStyleTween: An interpolation between twoTextStyles.
Texture: A rectangle upon which a backend texture is mapped.
ThreePointCubic: A cubic polynomial composed of two curves that share a common center point.
Threshold: A curve that is 0.0 until it hits the threshold, then it jumps to 1.0.
TickerFuture: An object representing an ongoingTicker sequence.
TickerMode: Enables or disables tickers (and thus animation controllers) in the widgetsubtree.
TickerProvider: An interface implemented by classes that can vendTicker objects.
Title: A widget that describes this app in the operating system.
ToggleablePainter: A base class for aCustomPainter that may be passed toToggleableStateMixin.buildToggleable to draw the visual representation ofa Toggleable.
Tolerance: Structure that specifies maximum allowable magnitudes for distances,durations, and velocity differences to be considered equal.
ToolbarItemsParentData: ParentData that determines whether or not to paint the corresponding child.
ToolbarOptions: Toolbar configuration forEditableText.
TrackingScrollController: AScrollController whoseinitialScrollOffset tracks its most recentlyupdatedScrollPosition.
TrainHoppingAnimation: This animation starts by proxying one animation, but when the value of thatanimation crosses the value of the second (either because the second isgoing in the opposite direction, or because the one overtakes the other),the animation hops over to proxying the second animation.
Transform: A widget that applies a transformation before painting its child.
TransformationController: A thin wrapper onValueNotifier whose value is aMatrix4 representing atransformation.
TransformProperty: Property which handlesMatrix4 that represent transforms.
TransitionDelegate<T>: The delegate that decides how pages added and removed fromNavigator.pagestransition in or out of the screen.
TransitionRoute<T>: A route with entrance and exit transitions.
TransposeCharactersIntent: AnIntent that represents a user interaction that attempts to swap thecharacters immediately around the cursor.
TreeSliver<T>: A widget that displaysTreeSliverNodes that expand and collapse in avertically and horizontally scrollingViewport.
TreeSliverController: Enables control over theTreeSliverNodes of aTreeSliver.
TreeSliverNode<T>: A data structure for configuring children of aTreeSliver.
Tween<T extendsObject?>: A linear interpolation between a beginning and ending value.
TweenAnimationBuilder<T extendsObject?>: Widget builder that animates a property of aWidget to a target valuewhenever the target value changes.
TweenSequence<T>: Enables creating anAnimation whose value is defined by a sequence ofTweens.
TweenSequenceItem<T>: A simple holder for one element of aTweenSequence.
TwoDimensionalChildBuilderDelegate: A delegate that supplies children for aTwoDimensionalScrollView using abuilder callback.
TwoDimensionalChildDelegate: A delegate that supplies children for scrolling in two dimensions.
TwoDimensionalChildListDelegate: A delegate that supplies children for aTwoDimensionalViewport using anexplicit two dimensional array.
TwoDimensionalChildManager: A delegate used byRenderTwoDimensionalViewport to manage its children.
TwoDimensionalScrollable: A widget that manages scrolling in both the vertical and horizontaldimensions and informs theTwoDimensionalViewport through which thecontent is viewed.
TwoDimensionalScrollableState: State object for aTwoDimensionalScrollable widget.
TwoDimensionalScrollView: A widget that combines aTwoDimensionalScrollable and aTwoDimensionalViewport to create an interactive scrolling pane of contentin both vertical and horizontal dimensions.
TwoDimensionalViewport: A widget through which a portion of larger content can be viewed, typicallyin combination with aTwoDimensionalScrollable.
TwoDimensionalViewportParentData: Parent data structure used byRenderTwoDimensionalViewport.
UiKitView: Embeds an iOS view in the Widget hierarchy.
UnconstrainedBox: A widget that imposes no constraints on its child, allowing it to renderat its "natural" size.
UndoHistory<T>: Provides undo/redo capabilities for aValueNotifier.
UndoHistoryController: A controller for the undo history, for example for an editable text field.
UndoHistoryState<T>: State for aUndoHistory.
UndoHistoryValue: Represents whether the current undo stack can undo or redo.
UndoTextIntent: AnIntent that represents a user interaction that attempts to go back tothe previous editing state.
UniqueKey: A key that is only equal to itself.
UniqueWidget<T extendsState<StatefulWidget>>: Base class for stateful widgets that have exactly one inflated instance inthe tree.
UnmanagedRestorationScope: Inserts a providedRestorationBucket into the widget tree and makes itavailable to descendants viaRestorationScope.of.
UpdateSelectionIntent: AnIntent that represents a user interaction that attempts to change theselection in an input field.
UserScrollNotification: A notification that the user has changed theScrollDirection in which theyare scrolling, or have stopped scrolling.
ValueKey<T>: A key that uses a value of a particular type to identify itself.
ValueListenableBuilder<T>: A widget whose content stays synced with aValueListenable.
ValueNotifier<T>: AChangeNotifier that holds a single value.
Velocity: A velocity in two dimensions.
View: Bootstraps a render tree that is rendered into the providedFlutterView.
ViewAnchor: Decorates achild widget with a sideView.
ViewCollection: A collection of siblingViews.
Viewport: A widget through which a portion of larger content can be viewed, typicallyin combination with aScrollable.
Visibility: Whether to show or hide a child.
VoidCallbackAction: AnAction that invokes theVoidCallback given to it in theVoidCallbackIntent passed to it when invoked.
VoidCallbackIntent: AnIntent that keeps aVoidCallback to be invoked by aVoidCallbackAction when it receives this intent.
WeakMap<K,V>: Does not hold keys from garbage collection.
Widget: Describes the configuration for anElement.
WidgetInspector: A widget that enables inspecting the child widget's structure.
WidgetOrderTraversalPolicy: AFocusTraversalPolicy that traverses the focus order in widget hierarchyorder.
WidgetsApp: A convenience widget that wraps a number of widgets that are commonlyrequired for an application.
WidgetsBindingObserver: Interface for classes that register with the Widgets layer binding.
WidgetsFlutterBinding: A concrete binding for applications based on the Widgets framework.
WidgetsLocalizations: Interface for localized resource values for the lowest levels of the Flutterframework.
WidgetSpan: An immutable widget that is embedded inline within text.
WidgetStateBorderSide: Defines aBorderSide whose value depends on a set ofWidgetStateswhich represent the interactive state of a component.
WidgetStateColor: Defines aColor that is also aWidgetStateProperty.
WidgetStateMapper<T>: Uses aWidgetStateMap to resolve to a single value of typeT based onthe current set of Widget states.
WidgetStateMouseCursor: Defines aMouseCursor whose value depends on a set ofWidgetStates whichrepresent the interactive state of a component.
WidgetStateOutlinedBorder: Defines anOutlinedBorder whose value depends on a set ofWidgetStateswhich represent the interactive state of a component.
WidgetStateProperty<T>: Interface for classes thatresolve to a value of typeT basedon a widget's interactive "state", which is defined as a setofWidgetStates.
WidgetStatePropertyAll<T>: Convenience class for creating aWidgetStateProperty thatresolves to the given value for all states.
WidgetStatesConstraint: This class allowsWidgetState enum values to be combinedusingWidgetStateOperators.
WidgetStatesController: Manages a set ofWidgetStates and notifies listeners of changes.
WidgetStateTextStyle: Defines aTextStyle that is also aWidgetStateProperty.
WidgetToRenderBoxAdapter: An adapter for placing a specificRenderBox in the widget tree.
WillPopScope: Registers a callback to veto attempts by the user to dismiss the enclosingModalRoute.
WordBoundary: ATextBoundary subclass for locating word breaks.
Wrap: A widget that displays its children in multiple horizontal or vertical runs.

Enums

AndroidOverscrollIndicator: Types of overscroll indicators supported byTargetPlatform.android.
AnimationBehavior: Configures how anAnimationController behaves when animations aredisabled.
AnimationStatus: The status of an animation.
AppLifecycleState: States that an application can be in once it is running.
AutofillContextAction: Predefined autofill context clean up actions.
AutovalidateMode: Used to configure the auto validation ofFormField andForm widgets.
Axis: The two cardinal directions in two dimensions.
AxisDirection: A direction along either the horizontal or verticalAxis in which theorigin, or zero position, is determined.
BannerLocation: Where to show aBanner.
BlendMode: Algorithms to use when painting on the canvas.
BlurStyle: Styles to use for blurs inMaskFilter objects.
BorderStyle: The style of line to draw for aBorderSide in aBorder.
BoxFit: How a box should be inscribed into another box.
BoxShape: The shape to use when rendering aBorder orBoxDecoration.
Brightness: Describes the contrast of a theme or color palette.
ChangeReportingBehavior: The behavior of reporting the selected item index in aListWheelScrollView.
Clip: Different ways to clip content.
ClipboardStatus: An enumeration of the status of the content on the user's clipboard.
ConnectionState: The state of connection to an asynchronous computation.
ContextMenuButtonType: The buttons that can appear in a context menu by default.
CrossAxisAlignment: How the children should be placed along the cross axis in a flex layout.
CrossFadeState: Specifies which of two children to show. SeeAnimatedCrossFade.
DecorationPosition: Where to paint a box decoration.
DiagnosticLevel: The various priority levels used to filter which diagnostics are shown andomitted.
DiagonalDragBehavior: Specifies how to configure theDragGestureRecognizers of aTwoDimensionalScrollable.
DismissDirection: The direction in which aDismissible can be dismissed.
FilterQuality: Quality levels for image sampling inImageFilter andShader objects that sampleimages and forCanvas operations that render images.
FlexFit: How the child is inscribed into the available space.
FloatingHeaderSnapMode: Specifies how a partially visibleSliverFloatingHeader animatesinto a view when a user scroll gesture ends.
FlutterLogoStyle: Possible ways to draw Flutter's logo.
FocusHighlightMode: An enum to describe which kind of focus highlight behavior to use whendisplaying focus information.
FocusHighlightStrategy: An enum to describe how the current value ofFocusManager.highlightMode isdetermined. The strategy is set onFocusManager.highlightStrategy.
FontStyle: Whether to use the italic type variation of glyphs in the font.
GrowthDirection: The direction in which a sliver's contents are ordered, relative to thescroll offset axis.
HeroFlightDirection: Direction of the hero's flight based on the navigation operation.
HitTestBehavior: How to behave during hit tests.
ImageRepeat: How to paint any portions of a box not covered by an image.
InspectorButtonVariant: Defines the visual and behavioral variants for anInspectorButton.
KeyEventResult: An enum that describes how to handle a key event handled by aFocusOnKeyCallback orFocusOnKeyEventCallback.
LiveTextInputStatus: An enumeration that indicates whether the current device is available for Live Text input.
LockState: Determines how the state of a lock key is used to accept a shortcut.
MainAxisAlignment: How the children should be placed along the main axis in a flex layout.
MainAxisSize: How much space should be occupied in the main axis.
NavigationMode: Describes the navigation mode to be set by aMediaQuery widget.
OptionsViewOpenDirection: A direction in which to open the options-view overlay.
Orientation: Whether in portrait or landscape.
OverflowBarAlignment: Defines the horizontal alignment ofOverflowBar childrenwhen they're laid out in an overflow column.
OverlayChildLocation: The location of theOverlay that anOverlayPortal renders its overlaychild on.
PaintingStyle: Strategies for painting shapes and paths on a canvas.
PanAxis: This enum is used to specify the behavior of theInteractiveViewer whenthe user drags the viewport.
PathFillType: Determines the winding rule that decides how the interior of aPath iscalculated.
PathOperation: Strategies for combining paths.
PlaceholderAlignment: Where to vertically align the placeholder relative to the surrounding text.
PlatformProvidedMenuItemType: The list of possible platform provided, prebuilt menus for use in aPlatformMenuBar.
RenderComparison: The description of the difference between two objects, in the context of howit will affect the rendering.
ResizeImagePolicy: Configures the behavior forResizeImage.
RouteInformationReportingType: TheRouter's intention when it reports a newRouteInformation to theRouteInformationProvider.
RoutePopDisposition: Indicates whether the current route should be popped.
ScrollbarOrientation: An orientation along either the horizontal or verticalAxis.
ScrollDecelerationRate: The rate at which scroll momentum will be decelerated.
ScrollIncrementType: Describes the type of scroll increment that will be performed by aScrollAction on aScrollable.
ScrollPositionAlignmentPolicy: The policy to use when applying thealignment parameter ofScrollPosition.ensureVisible.
ScrollViewKeyboardDismissBehavior: A representation of how aScrollView should dismiss the on-screenkeyboard.
SelectableRegionSelectionStatus: The status of the selection under aSelectableRegion.
SelectionChangedCause: Indicates what triggered the change in selected text (including changes tothe cursor location).
SliverPaintOrder: Specifies an order in which to paint the slivers of aViewport.
SmartDashesType: Indicates how to handle the intelligent replacement of dashes in text input.
SmartQuotesType: Indicates how to handle the intelligent replacement of quotes in text input.
SnapshotMode: Controls how theSnapshotWidget paints its child.
StackFit: How to size the non-positioned children of aStack.
StandardComponentType: An enum identifying standard UI components.
StrokeCap: Styles to use for line endings.
StrokeJoin: Styles to use for line segment joins.
TableCellVerticalAlignment: Vertical alignment options for cells inRenderTable objects.
TargetPlatform: The platform that user interaction should adapt to target.
TextAffinity: A way to disambiguate aTextPosition when its offset could match twodifferent locations in the rendered string.
TextAlign: Whether and how to align text horizontally.
TextBaseline: A horizontal line used for aligning text.
TextDecorationStyle: The style in which to draw a text decoration
TextDirection: A direction in which text flows.
TextLeadingDistribution: How the"leading" is distributedover and under the text.
TextOverflow: How overflowing text should be handled.
TextSelectionHandleType: The type of selection handle to be displayed.
TextWidthBasis: The different ways of measuring the width of one or more lines of text.
TileMode: Defines how to handle areas outside the defined bounds of a gradient or image filter.
TraversalDirection: A direction along either the horizontal or vertical axes.
TraversalEdgeBehavior: Controls the focus transfer at the edges of aFocusScopeNode.For movement transfers (previous or next), the edge representsthe first or last items. For directional transfers, the edgerepresents the outermost items of theFocusScopeNode, For example:for moving downwards, the edge node is the one with the largest bottomcoordinate; for moving leftwards, the edge node is the one with thesmallest x coordinate.
UnfocusDisposition: Describe what should happen afterFocusNode.unfocus is called.
VertexMode: Defines how a list of points is interpreted when drawing a set of triangles.
VerticalDirection: A direction in which boxes flow vertically.
WebHtmlElementStrategy: The strategy forImage.network andNetworkImage to decide whether todisplay images in HTML elements contained in a platform view instead offetching bytes.
WidgetInspectorServiceExtensions: Service extension constants for the Widget Inspector.
WidgetsServiceExtensions: Service extension constants for the widgets library.
WidgetState: Interactive states that some of the widgets can take on when receiving inputfrom the user.
WrapAlignment: HowWrap should align objects.
WrapCrossAlignment: WhoWrap should align children within a run in the cross axis.

Mixins

AnimationEagerListenerMixin: A mixin that replaces thedidRegisterListener/didUnregisterListener contractwith a dispose contract.
AnimationLazyListenerMixin: A mixin that helps listen to another object only when this object has registered listeners.
AnimationLocalListenersMixin: A mixin that implements theaddListener/removeListener protocol and notifiesall the registered listeners whennotifyListeners is called.
AnimationLocalStatusListenersMixin: A mixin that implements the addStatusListener/removeStatusListener protocoland notifies all the registered listeners when notifyStatusListeners iscalled.
AnimationWithParentMixin<T>: Implements most of theAnimation interface by deferring its behavior to agivenparent Animation.
AutomaticKeepAliveClientMixin<T extendsStatefulWidget>: A mixin with convenience methods for clients ofAutomaticKeepAlive. It is usedwithState subclasses to manage keep-alive behavior in lazily built lists.
DirectionalFocusTraversalPolicyMixin: A mixin class that provides an implementation for finding a node in aparticular direction.
LocalHistoryRoute<T>: A mixin used by routes to handle back navigations internally by popping a list.
MenuSerializableShortcut: A mixin allowing aShortcutActivator to provide data for serialization ofthe shortcut when sending to the platform.
NotifiableElementMixin: Mixin this class to allow receivingNotification objects dispatched bychild elements.
PaintingBinding: Binding for the painting library.
PopNavigatorRouterDelegateMixin<T>: A mixin that wiresRouterDelegate.popRoute to theNavigator it builds.
RadioClient<T>: A client for aRadioGroupRegistry.
RenderAbstractLayoutBuilderMixin<LayoutInfoType,ChildType extendsRenderObject>: Generic mixin forRenderObjects created by anAbstractLayoutBuilder withthe the sameLayoutInfoType.
RestorationMixin<S extendsStatefulWidget>: Manages the restoration data for aState object of aStatefulWidget.
RootElementMixin: Mixin for the element at the root of the tree.
ScrollMetrics: A description of aScrollable's contents, useful for modeling the stateof its viewport.
SingleTickerProviderStateMixin<T extendsStatefulWidget>: Provides a singleTicker that is configured to only tick while the currenttree is enabled, as defined byTickerMode.
SlottedContainerRenderObjectMixin<SlotType,ChildType extendsRenderObject>: Mixin for aRenderObject configured by aSlottedMultiChildRenderObjectWidget.
SlottedMultiChildRenderObjectWidgetMixin<SlotType,ChildType extendsRenderObject>: A mixin version ofSlottedMultiChildRenderObjectWidget.
TextSelectionDelegate: A mixin for manipulating the selection, provided for toolbar or shortcutkeys.
TextSelectionHandleControls: TextSelectionControls that specifically do not manage the toolbar in orderto leave that toEditableText.contextMenuBuilder.
TickerProviderStateMixin<T extendsStatefulWidget>: ProvidesTicker objects that are configured to only tick while the currenttree is enabled, as defined byTickerMode.
ToggleableStateMixin<S extendsStatefulWidget>: A mixin forStatefulWidgets that implement toggleablecontrols with toggle animations (e.g.Switches,CupertinoSwitches,Checkboxes,CupertinoCheckboxes,Radios, andCupertinoRadios).
TreeSliverStateMixin<T>: A mixin for classes implementing a tree structure as expected by aTreeSliverController.
ViewportElementMixin: A mixin that allowsElements containingViewport like widgets to correctlymodify the notification depth of aViewportNotificationMixin.
ViewportNotificationMixin: Mixin forNotifications that track how manyRenderAbstractViewport theyhave bubbled through.
WidgetInspectorService: Service used by GUI tools to interact with theWidgetInspector.
WidgetsBinding: The glue between the widgets layer and the Flutter engine.

Extension Types

OverlayChildLayoutInfo: The additional layout information available to theOverlayPortal.overlayChildLayoutBuilder callback.

Extensions

StringCharacters onString
WidgetStateOperators onWidgetStatesConstraint: These operators can be used inside aWidgetStateMap to combine statesand find a match.

Constants

factory→ const _Factory: Used to annotate an instance or static methodm. Indicates thatm musteither be abstract or must return a newly allocated object ornull. Inaddition, every method that either implements or overridesm is implicitlyannotated with this same annotation.
immutable→ constImmutable: Used to annotate a classC. Indicates thatC and all subtypes ofCmust be immutable.
kAlwaysCompleteAnimation→ constAnimation<double>: An animation that is always complete.
kAlwaysDismissedAnimation→ constAnimation<double>: An animation that is always dismissed.
kDefaultContentInsertionMimeTypes→ constList<String>: The default mime types to be used when allowedMimeTypes is not provided.
kDefaultFontSize→ constdouble: The default font size if none is specified.
kDefaultRouteDirectionalTraversalEdgeBehavior→ constTraversalEdgeBehavior: The default value ofNavigator.routeDirectionalTraversalEdgeBehavior.
kDefaultRouteTraversalEdgeBehavior→ constTraversalEdgeBehavior: The default value ofNavigator.routeTraversalEdgeBehavior.
kTextHeightNone→ constdouble: ATextStyle.height value that indicates the text span should takethe height defined by the font, which may not be exactly the height ofTextStyle.fontSize.
mustCallSuper→ const _MustCallSuper: Used to annotate an instance member (method, getter, setter, operator, orfield)m. Indicates that every invocation of a member that overridesmmust also invokem. In addition, every method that overridesm isimplicitly annotated with this same annotation.
optionalTypeArgs→ const _OptionalTypeArgs: Used to annotate a class, mixin, extension, function, method, or typedefdeclarationC. Indicates that any type arguments declared onC are tobe treated as optional.
protected→ const _Protected: Used to annotate an instance member in a class or mixin which is meant tobe visible only within the declaring library, and to other instance membersof the class or mixin, and their subtypes.
required→ constRequired: Used to annotate a named parameterp in a method or functionf.Indicates that every invocation off must include an argumentcorresponding top, despite the fact thatp would otherwise be anoptional parameter.
staticIconProvider→ constObject: Annotation for classes that only provide static constIconData instances.
visibleForTesting→ const _VisibleForTesting: Used to annotate a declaration that was made public, so that it is morevisible than otherwise necessary, to make code testable.
widgetFactory→ const _WidgetFactory: Annotation which marks a function as a widget factory for the purpose ofwidget creation tracking.

Properties

debugCaptureShaderWarmUpImage↔ShaderWarmUpImageCallback: Called byShaderWarmUp.execute immediately after it creates anImage.
getter/setter pair
debugCaptureShaderWarmUpPicture↔ShaderWarmUpPictureCallback: Called byShaderWarmUp.execute immediately after it creates aPicture.
getter/setter pair
debugDisableShadows↔bool: Whether to replace all shadows with solid color blocks.
getter/setter pair
debugEnhanceBuildTimelineArguments↔bool: Adds debugging information toTimeline events related toWidget builds.
getter/setter pair
debugFocusChanges↔bool: Setting to true will cause extensive logging to occur when focus changes occur.
getter/setter pair
debugHighlightDeprecatedWidgets↔bool: Show banners for deprecated widgets.
getter/setter pair
debugImageOverheadAllowance↔int: The number of bytes an image must use before it triggers inversion whendebugInvertOversizedImages is true.
getter/setter pair
debugInvertOversizedImages↔bool: If true, the framework will color invert and horizontally flip images thathave been decoded to a size taking at leastdebugImageOverheadAllowancebytes more than necessary.
getter/setter pair
debugNetworkImageHttpClientProvider↔HttpClientProvider?: Provider from whichNetworkImage will get itsHttpClient in debug builds.
getter/setter pair
debugOnPaintImage↔PaintImageCallback?: If not null, called when the framework is about to paint anImage to aCanvas with anImageSizeInfo that contains the decoded size of theimage as well as its output size.
getter/setter pair
debugOnRebuildDirtyWidget↔RebuildDirtyWidgetCallback?: Callback invoked for every dirty widget built each frame.
getter/setter pair
debugPrint↔DebugPrintCallback: Prints a message to the console, which you can access using the "flutter"tool's "logs" command ("flutter logs").
getter/setter pair
debugPrintBuildScope↔bool: Log all calls toBuildOwner.buildScope.
getter/setter pair
debugPrintGlobalKeyedWidgetLifecycle↔bool: Log when widgets with global keys are deactivated and log when they arereactivated (retaken).
getter/setter pair
debugPrintRebuildDirtyWidgets↔bool: Log the dirty widgets that are built each frame.
getter/setter pair
debugPrintScheduleBuildForStacks↔bool: Log the call stacks that mark widgets as needing to be rebuilt.
getter/setter pair
debugProfileBuildsEnabled↔bool: AddsTimeline events for every Widget built.
getter/setter pair
debugProfileBuildsEnabledUserWidgets↔bool: AddsTimeline events for every user-createdWidget built.
getter/setter pair
emptyTextSelectionControls→TextSelectionControls: Text selection controls that do not show any toolbars or handles.
final
imageCache→ImageCache: The singleton that implements the Flutter framework's image cache.
no setter
primaryFocus→FocusNode?: Provides convenient access to the currentFocusManager.primaryFocus fromtheWidgetsBinding instance.
no setter

Functions

applyBoxFit(BoxFitfit,SizeinputSize,SizeoutputSize)→FittedSizes: Apply aBoxFit value.
axisDirectionIsReversed(AxisDirectionaxisDirection)→bool: Returns whether traveling along the given axis direction visits coordinatesalong that axis in numerically decreasing order.
axisDirectionToAxis(AxisDirectionaxisDirection)→Axis: Returns theAxis that contains the givenAxisDirection.
basicLocaleListResolution(List<Locale>?preferredLocales,Iterable<Locale>supportedLocales)→Locale: The default locale resolution algorithm.
buildTextSpanWithSpellCheckSuggestions(TextEditingValuevalue,boolcomposingWithinCurrentTextRange,TextStyle?style,TextStylemisspelledTextStyle,SpellCheckResultsspellCheckResults)→TextSpan: Builds theTextSpan tree given the current state of the text input andspell check results.
childDragAnchorStrategy(Draggable<Object>draggable,BuildContextcontext,Offsetposition)→Offset: Display the feedback anchored at the position of the original child.
combineKeyEventResults(Iterable<KeyEventResult>results)→KeyEventResult: Combine the results returned by multipleFocusOnKeyCallbacks orFocusOnKeyEventCallbacks.
combineSemanticsInfo(List<InlineSpanSemanticsInformation>infoList)→List<InlineSpanSemanticsInformation>: Combines _semanticsInfo entries where permissible.
createLocalImageConfiguration(BuildContextcontext, {Size?size})→ImageConfiguration: Creates anImageConfiguration based on the givenBuildContext (andoptionally size).
debugAssertAllPaintingVarsUnset(Stringreason, {booldebugDisableShadowsOverride =false})→bool: Returns true if none of the painting library debug variables have been changed.
debugAssertAllWidgetVarsUnset(Stringreason)→bool: Returns true if none of the widget library debug variables have been changed.
debugCheckCanResolveTextDirection(TextDirection?direction,Stringtarget)→bool: Asserts that a givenTextDirection is not null.
debugCheckHasDirectionality(BuildContextcontext, {String?why,String?hint,String?alternative})→bool: Asserts that the given context has aDirectionality ancestor.
debugCheckHasMediaQuery(BuildContextcontext)→bool: Asserts that the given context has aMediaQuery ancestor.
debugCheckHasOverlay(BuildContextcontext)→bool: Asserts that the given context has anOverlay ancestor.
debugCheckHasTable(BuildContextcontext)→bool: Asserts that the given context has aTable ancestor.
debugCheckHasWidgetsLocalizations(BuildContextcontext)→bool: Asserts that the given context has aLocalizations ancestor that containsaWidgetsLocalizations delegate.
debugChildrenHaveDuplicateKeys(Widgetparent,Iterable<Widget>children, {String?message})→bool: Asserts if the given child list contains any duplicate non-null keys.
debugDescribeFocusTree()→String: Returns a text representation of the current focus tree, along with thecurrent attributes on each node.
debugDescribeTransform(Matrix4?transform)→List<String>: Returns a list of strings representing the given transform in a formatuseful forTransformProperty.
debugDumpApp()→ void: Print a string representation of the currently running app.
debugDumpFocusTree()→ void: Prints a text representation of the current focus tree, along with thecurrent attributes on each node.
debugDumpLayerTree()→ void: Prints a textual representation of the layer trees.
debugDumpRenderTree()→ void: Prints a textual representation of the render trees.
debugFlushLastFrameImageSizeInfo()→ void: Flushes inter-frame tracking of image size information frompaintImage.
debugIsLocalCreationLocation(Objectobject)→bool: Returns if an object is user created.
debugIsWidgetLocalCreation(Widgetwidget)→bool: Returns true if aWidget is user created.
debugItemsHaveDuplicateKeys(Iterable<Widget>items)→bool: Asserts if the given list of items contains any duplicate non-null keys.
debugPrintStack({StackTrace?stackTrace,String?label,int?maxFrames})→ void: Dump the stack to the console usingdebugPrint andFlutterError.defaultStackFilter.
debugTransformDebugCreator(Iterable<DiagnosticsNode>properties)→Iterable<DiagnosticsNode>: Transformer to parse and gather information aboutDiagnosticsDebugCreator.
debugWidgetBuilderValue(Widgetwidget,Widget?built)→ void: Asserts that thebuilt widget is not null.
decodeImageFromList(Uint8Listbytes)→Future<Image>: Creates an image from a list of bytes.
defaultScrollNotificationPredicate(ScrollNotificationnotification)→bool: AScrollNotificationPredicate that checks whethernotification.depth == 0, which means that the notification did not bubblethrough any intervening scrolling widgets.
flipAxis(Axisdirection)→Axis: Returns the opposite of the givenAxis.
flipAxisDirection(AxisDirectionaxisDirection)→AxisDirection: Returns the opposite of the givenAxisDirection.
getAxisDirectionFromAxisReverseAndDirectionality(BuildContextcontext,Axisaxis,boolreverse)→AxisDirection: Returns theAxisDirection in the givenAxis in the currentDirectionality (or the reverse ifreverse is true).
intentForMacOSSelector(StringselectorName)→Intent?: Maps the selector from NSStandardKeyBindingResponding to the Intent if theselector is recognized.
lerpFontVariations(List<FontVariation>?a,List<FontVariation>?b,doublet)→List<FontVariation>?: Interpolate between two lists ofFontVariation objects.
paintBorder(Canvascanvas,Rectrect, {BorderSidetop =BorderSide.none,BorderSideright =BorderSide.none,BorderSidebottom =BorderSide.none,BorderSideleft =BorderSide.none})→ void: Paints a border around the given rectangle on the canvas.
paintImage({requiredCanvascanvas,requiredRectrect,requiredImageimage,String?debugImageLabel,doublescale =1.0,doubleopacity =1.0,ColorFilter?colorFilter,BoxFit?fit,Alignmentalignment =Alignment.center,Rect?centerSlice,ImageRepeatrepeat =ImageRepeat.noRepeat,boolflipHorizontally =false,boolinvertColors =false,FilterQualityfilterQuality =FilterQuality.medium,boolisAntiAlias =false,BlendModeblendMode =BlendMode.srcOver})→ void: Paints an image into the given rectangle on the canvas.
paintZigZag(Canvascanvas,Paintpaint,Offsetstart,Offsetend,intzigs,doublewidth)→ void: Draw a line between two points, which cuts diagonally back and forth acrossthe line that connects the two points.
pointerDragAnchorStrategy(Draggable<Object>draggable,BuildContextcontext,Offsetposition)→Offset: Display the feedback anchored at the position of the touch that startedthe drag.
positionDependentBox({requiredSizesize,requiredSizechildSize,requiredOffsettarget,requiredboolpreferBelow,doubleverticalOffset =0.0,doublemargin =10.0})→Offset: Position a child box within a container box, either above or below a targetpoint.
precacheImage(ImageProvider<Object>provider,BuildContextcontext, {Size?size,ImageErrorListener?onError})→Future<void>: Prefetches an image into the image cache.
runApp(Widgetapp)→ void: Inflate the given widget and attach it to the view.
runWidget(Widgetapp)→ void: Inflate the given widget and bootstrap the widget tree.
showGeneralDialog<T extendsObject?>({requiredBuildContextcontext,requiredRoutePageBuilderpageBuilder,boolbarrierDismissible =false,String?barrierLabel,ColorbarrierColor =const Color(0x80000000),DurationtransitionDuration =const Duration(milliseconds: 200),RouteTransitionsBuilder?transitionBuilder,booluseRootNavigator =true,boolfullscreenDialog =false,RouteSettings?routeSettings,Offset?anchorPoint,bool?requestFocus})→Future<T?>: Displays a dialog above the current contents of the app.
textDirectionToAxisDirection(TextDirectiontextDirection)→AxisDirection: Returns theAxisDirection in which reading occurs in the givenTextDirection.

Typedefs

ActionListenerCallback= void Function(Action<Intent>action): The kind of callback that anAction uses to notify of changes to theaction's state.
AnimatableCallback<T>= T Function(doublevalue): A typedef used byAnimatable.fromCallback to create anAnimatablefrom a callback.
AnimatedCrossFadeBuilder=Widget Function(WidgettopChild,KeytopChildKey,WidgetbottomChild,KeybottomChildKey): Signature for theAnimatedCrossFade.layoutBuilder callback.
AnimatedItemBuilder=Widget Function(BuildContextcontext,intindex,Animation<double>animation): Signature for the builder callback used byAnimatedList,AnimatedList.separated&AnimatedGrid to build their animated children.
AnimatedRemovedItemBuilder=Widget Function(BuildContextcontext,Animation<double>animation): Signature for the builder callback used inAnimatedListState.removeItem andAnimatedGridState.removeItem to animate their children after they havebeen removed.
AnimatedSwitcherLayoutBuilder=Widget Function(Widget?currentChild,List<Widget>previousChildren): Signature for builders used to generate custom layouts forAnimatedSwitcher.
AnimatedSwitcherTransitionBuilder=Widget Function(Widgetchild,Animation<double>animation): Signature for builders used to generate custom transitions forAnimatedSwitcher.
AnimatedTransitionBuilder=Widget Function(BuildContextcontext,Animation<double>animation,Widget?child): Builder callback used byDualTransitionBuilder.
AnimationStatusListener= void Function(AnimationStatusstatus): Signature for listeners attached usingAnimation.addStatusListener.
AppExitRequestCallback=Future<AppExitResponse> Function(): A callback type that is used byAppLifecycleListener.onExitRequested toask the application if it wants to cancel application termination or not.
AppPrivateCommandCallback= void Function(Stringaction,Map<String,dynamic>data): Signature for the callback that reports the app private command results.
AsyncWidgetBuilder<T>=Widget Function(BuildContextcontext,AsyncSnapshot<T>snapshot): Signature for strategies that build widgets based on asynchronousinteraction.
AutocompleteFieldViewBuilder=Widget Function(BuildContextcontext,TextEditingControllertextEditingController,FocusNodefocusNode,VoidCallbackonFieldSubmitted): The type of the Autocomplete callback which returns the widget thatcontains the inputTextField orTextFormField.
AutocompleteOnSelected<T extendsObject>= void Function(Toption): The type of the callback used by theRawAutocomplete widget to indicatethat the user has selected an option.
AutocompleteOptionsBuilder<T extendsObject>=FutureOr<Iterable<T>> Function(TextEditingValuetextEditingValue): The type of theRawAutocomplete callback which computes the list ofoptional completions for the widget's field, based on the text the user hasentered so far.
AutocompleteOptionsViewBuilder<T extendsObject>=Widget Function(BuildContextcontext,AutocompleteOnSelected<T>onSelected,Iterable<T>options): The type of theRawAutocomplete callback which returns aWidget thatdisplays the specifiedoptions and callsonSelected if the userselects an option.
AutocompleteOptionToString<T extendsObject>=String Function(Toption): The type of theRawAutocomplete callback that converts an option value toa string which can be displayed in the widget's options menu.
BoxConstraintsTransform=BoxConstraints Function(BoxConstraintsconstraints): Signature for a function that transforms aBoxConstraints to anotherBoxConstraints.
ChildIndexGetter=int? Function(Keykey): Called to find the new index of a child based on itskey in case ofreordering.
ConditionalElementVisitor=bool Function(Elementelement): Signature for the callback toBuildContext.visitAncestorElements.
ConfirmDismissCallback=Future<bool?> Function(DismissDirectiondirection): Signature used byDismissible to give the application an opportunity toconfirm or veto a dismiss gesture.
CreatePlatformViewCallback=PlatformViewController Function(PlatformViewCreationParamsparams): Constructs aPlatformViewController.
CreateRectTween=Tween<Rect?> Function(Rect?begin,Rect?end): Signature for a function that takes twoRect instances and returns aRectTween that transitions between them.
DecoderBufferCallback=Future<Codec> Function(ImmutableBufferbuffer, {boolallowUpscaling,int?cacheHeight,int?cacheWidth}): Performs the decode process for use inImageProvider.loadBuffer.
DelegatedTransitionBuilder=Widget? Function(BuildContextcontext,Animation<double>animation,Animation<double>secondaryAnimation,boolallowSnapshotting,Widget?child): Signature for a builder used to control a page's exit transition.
DidRemovePageCallback= void Function(Page<Object?>page): Signature for theNavigator.onDidRemovePage callback.
DismissDirectionCallback= void Function(DismissDirectiondirection): Signature used byDismissible to indicate that it has been dismissed inthe givendirection.
DismissUpdateCallback= void Function(DismissUpdateDetailsdetails): Signature used byDismissible to indicate that the dismissible has been dragged.
DragAnchorStrategy=Offset Function(Draggable<Object>draggable,BuildContextcontext,Offsetposition): Signature for the strategy that determines the drag start point of aDraggable.
DragEndCallback= void Function(DraggableDetailsdetails): Signature for when the draggable is dropped.
DraggableCanceledCallback= void Function(Velocityvelocity,Offsetoffset): Signature for when aDraggable is dropped without being accepted by aDragTarget.
DragTargetAccept<T>= void Function(Tdata): Signature for causing aDragTarget to accept the given data.
DragTargetAcceptWithDetails<T>= void Function(DragTargetDetails<T>details): Signature for determining information about the acceptance by aDragTarget.
DragTargetBuilder<T>=Widget Function(BuildContextcontext,List<T?>candidateData,ListrejectedData): Signature for building children of aDragTarget.
DragTargetLeave<T>= void Function(T?data): Signature for when aDraggable leaves aDragTarget.
DragTargetMove<T>= void Function(DragTargetDetails<T>details): Signature for when aDraggable moves within aDragTarget.
DragTargetWillAccept<T>=bool Function(T?data): Signature for determining whether the given data will be accepted by aDragTarget.
DragTargetWillAcceptWithDetails<T>=bool Function(DragTargetDetails<T>details): Signature for determining whether the given data will be accepted by aDragTarget,based on provided information.
DragUpdateCallback= void Function(DragUpdateDetailsdetails): Signature for when aDraggable is dragged across the screen.
EditableTextContextMenuBuilder=Widget Function(BuildContextcontext,EditableTextStateeditableTextState): Signature for a widget builder that builds a context menu for the givenEditableTextState.
ElementCreatedCallback= void Function(Objectelement): The signature of the function that gets called when theHtmlElementViewDOM element is created.
ElementVisitor= void Function(Elementelement): Signature for the callback toBuildContext.visitChildElements.
ErrorWidgetBuilder=Widget Function(FlutterErrorDetailsdetails): Signature for the constructor that is called when an error occurs whilebuilding a widget.
ExitWidgetSelectionButtonBuilder=Widget Function(BuildContextcontext, {requiredGlobalKey<State<StatefulWidget>>key,requiredVoidCallbackonPressed,requiredStringsemanticsLabel}): Signature for the builder callback used byWidgetInspector.exitWidgetSelectionButtonBuilder.
ExpansibleBuilder=Widget Function(BuildContextcontext,Widgetheader,Widgetbody,Animation<double>animation): The type of the callback that uses the header and body of anExpansiblewidget to build the widget.
ExpansibleComponentBuilder=Widget Function(BuildContextcontext,Animation<double>animation): The type of the callback that returns the header or body of anExpansible.
FocusOnKeyCallback=KeyEventResult Function(FocusNodenode,RawKeyEventevent): Signature of a callback used byFocus.onKey andFocusScope.onKeyto receive key events.
FocusOnKeyEventCallback=KeyEventResult Function(FocusNodenode,KeyEventevent): Signature of a callback used byFocus.onKeyEvent andFocusScope.onKeyEventto receive key events.
FormFieldBuilder<T>=Widget Function(FormFieldState<T>field): Signature for building the widget representing the form field.
FormFieldErrorBuilder=Widget Function(BuildContextcontext,StringerrorText): Signature for a callback that builds an error widget.
FormFieldSetter<T>= void Function(T?newValue): Signature for being notified when a form field changes value.
FormFieldValidator<T>=String? Function(T?value): Signature for validating a form field.
GenerateAppTitle=String Function(BuildContextcontext): The signature ofWidgetsApp.onGenerateTitle.
GestureDragCancelCallback= void Function(): Signature for when the pointer that previously triggered aGestureDragDownCallback did not complete.
GestureDragDownCallback= void Function(DragDownDetailsdetails): Signature for when a pointer has contacted the screen and might begin tomove.
GestureDragEndCallback= void Function(DragEndDetailsdetails): Signature for when a pointer that was previously in contact with the screenand moving is no longer in contact with the screen.
GestureDragStartCallback= void Function(DragStartDetailsdetails): Signature for when a pointer has contacted the screen and has begun to move.
GestureDragUpdateCallback= void Function(DragUpdateDetailsdetails): Signature for when a pointer that is in contact with the screen and movinghas moved again.
GestureForcePressEndCallback= void Function(ForcePressDetailsdetails): Signature for when the pointer that previously triggered aForcePressGestureRecognizer.onStart callback is no longer in contactwith the screen.
GestureForcePressPeakCallback= void Function(ForcePressDetailsdetails): Signature used byForcePressGestureRecognizer for when a pointer that haspressed with at leastForcePressGestureRecognizer.peakPressure.
GestureForcePressStartCallback= void Function(ForcePressDetailsdetails): Signature used by aForcePressGestureRecognizer for when a pointer haspressed with at leastForcePressGestureRecognizer.startPressure.
GestureForcePressUpdateCallback= void Function(ForcePressDetailsdetails): Signature used byForcePressGestureRecognizer during the framesafter the triggering of aForcePressGestureRecognizer.onStart callback.
GestureLongPressCallback= void Function(): Callback signature forLongPressGestureRecognizer.onLongPress.
GestureLongPressEndCallback= void Function(LongPressEndDetailsdetails): Callback signature forLongPressGestureRecognizer.onLongPressEnd.
GestureLongPressMoveUpdateCallback= void Function(LongPressMoveUpdateDetailsdetails): Callback signature forLongPressGestureRecognizer.onLongPressMoveUpdate.
GestureLongPressStartCallback= void Function(LongPressStartDetailsdetails): Callback signature forLongPressGestureRecognizer.onLongPressStart.
GestureLongPressUpCallback= void Function(): Callback signature forLongPressGestureRecognizer.onLongPressUp.
GestureRecognizerFactoryConstructor<T extendsGestureRecognizer>= T Function(): Signature for closures that implementGestureRecognizerFactory.constructor.
GestureRecognizerFactoryInitializer<T extendsGestureRecognizer>= void Function(Tinstance): Signature for closures that implementGestureRecognizerFactory.initializer.
GestureScaleEndCallback= void Function(ScaleEndDetailsdetails): Signature for when the pointers are no longer in contact with the screen.
GestureScaleStartCallback= void Function(ScaleStartDetailsdetails): Signature for when the pointers in contact with the screen have establisheda focal point and initial scale of 1.0.
GestureScaleUpdateCallback= void Function(ScaleUpdateDetailsdetails): Signature for when the pointers in contact with the screen have indicated anew focal point and/or scale.
GestureTapCallback= void Function(): Signature for when a tap has occurred.
GestureTapCancelCallback= void Function(): Signature for when the pointer that previously triggered aGestureTapDownCallback will not end up causing a tap.
GestureTapDownCallback= void Function(TapDownDetailsdetails): Signature for when a pointer that might cause a tap has contacted thescreen.
GestureTapUpCallback= void Function(TapUpDetailsdetails): Signature for when a pointer that will trigger a tap has stopped contactingthe screen.
HeroFlightShuttleBuilder=Widget Function(BuildContextflightContext,Animation<double>animation,HeroFlightDirectionflightDirection,BuildContextfromHeroContext,BuildContexttoHeroContext): A function that letsHeroes self supply aWidget that is shown during thehero's flight from one route to another instead of default (which is toshow the destination route's instance of the Hero).
HeroPlaceholderBuilder=Widget Function(BuildContextcontext,SizeheroSize,Widgetchild): Signature for a function that builds aHero placeholder widget given achild and aSize.
HttpClientProvider=HttpClient Function(): Signature for a method that returns anHttpClient.
ImageChunkListener= void Function(ImageChunkEventevent): Signature for listening toImageChunkEvent events.
ImageDecoderCallback=Future<Codec> Function(ImmutableBufferbuffer, {TargetImageSizeCallback?getTargetSize}): Performs the decode process for use inImageProvider.loadImage.
ImageErrorListener= void Function(Objectexception,StackTrace?stackTrace): Signature for reporting errors when resolving images.
ImageErrorWidgetBuilder=Widget Function(BuildContextcontext,Objecterror,StackTrace?stackTrace): Signature used byImage.errorBuilder to create a replacement widget torender instead of the image.
ImageFrameBuilder=Widget Function(BuildContextcontext,Widgetchild,int?frame,boolwasSynchronouslyLoaded): Signature used byImage.frameBuilder to control the widget that will beused when anImage is built.
ImageListener= void Function(ImageInfoimage,boolsynchronousCall): Signature for callbacks reporting that an image is available.
ImageLoadingBuilder=Widget Function(BuildContextcontext,Widgetchild,ImageChunkEvent?loadingProgress): Signature used byImage.loadingBuilder to build a representation of theimage's loading progress.
IndexedWidgetBuilder=Widget Function(BuildContextcontext,intindex): Signature for a function that creates a widget for a given index, e.g., in alist.
InitialRouteListFactory=List<Route> Function(StringinitialRoute): The signature ofWidgetsApp.onGenerateInitialRoutes.
InlineSpanVisitor=bool Function(InlineSpanspan): Called on each span asInlineSpan.visitChildren walks theInlineSpan tree.
InspectorSelectionChangedCallback= void Function(): Signature for the selection change callback used byWidgetInspectorService.selectionChangedCallback.
InteractiveViewerWidgetBuilder=Widget Function(BuildContextcontext,Quadviewport): A signature for widget builders that take aQuad of the current viewport.
LayoutWidgetBuilder=Widget Function(BuildContextcontext,BoxConstraintsconstraints): The signature of theLayoutBuilder builder function.
LocaleListResolutionCallback=Locale? Function(List<Locale>?locales,Iterable<Locale>supportedLocales): The signature ofWidgetsApp.localeListResolutionCallback.
LocaleResolutionCallback=Locale? Function(Locale?locale,Iterable<Locale>supportedLocales): The signature ofWidgetsApp.localeResolutionCallback.
MagnifierBuilder=Widget? Function(BuildContextcontext,MagnifierControllercontroller,ValueNotifier<MagnifierInfo>magnifierInfo): Signature for a builder that builds aWidget with aMagnifierController.
MenuItemSerializableIdGenerator=int Function(PlatformMenuItemitem): The signature for a function that generates unique menu item IDs forserialization of aPlatformMenuItem.
MoveExitWidgetSelectionButtonBuilder=Widget Function(BuildContextcontext, {requiredVoidCallbackonPressed,requiredStringsemanticsLabel,boolusesDefaultAlignment}): Signature for the builder callback used byWidgetInspector.moveExitWidgetSelectionButtonBuilder.
NavigatorFinderCallback=NavigatorState Function(BuildContextcontext): A callback that given aBuildContext finds aNavigatorState.
NestedScrollViewHeaderSliversBuilder=List<Widget> Function(BuildContextcontext,boolinnerBoxIsScrolled): Signature used byNestedScrollView for building its header.
NotificationListenerCallback<T extendsNotification>=bool Function(Tnotification): Signature forNotification listeners.
NullableIndexedWidgetBuilder=Widget? Function(BuildContextcontext,intindex): Signature for a function that creates a widget for a given index, e.g., in alist, but may return null.
OnInvokeCallback<T extendsIntent>=Object? Function(Tintent): The signature of a callback accepted byCallbackAction.onInvoke.
OnKeyEventCallback=KeyEventResult Function(KeyEventevent): Signature of a callback used byFocusManager.addEarlyKeyEventHandler andFocusManager.addLateKeyEventHandler.
OrientationWidgetBuilder=Widget Function(BuildContextcontext,Orientationorientation): Signature for a function that builds a widget given anOrientation.
OverlayChildLayoutBuilder=Widget Function(BuildContextcontext,OverlayChildLayoutInfoinfo): The signature of the widget builder callback used inOverlayPortal.overlayChildLayoutBuilder.
PageRouteFactory=PageRoute<T> Function<T>(RouteSettingssettings,WidgetBuilderbuilder): The signature ofWidgetsApp.pageRouteBuilder.
PaintImageCallback= void Function(ImageSizeInfoinfo): Called when the framework is about to paint anImage to aCanvas with anImageSizeInfo that contains the decoded size of the image as well as itsoutput size.
PlatformViewSurfaceFactory=Widget Function(BuildContextcontext,PlatformViewControllercontroller): A factory for a surface presenting a platform view as part of the widget hierarchy.
PointerCancelEventListener= void Function(PointerCancelEventevent): Signature for listening toPointerCancelEvent events.
PointerDownEventListener= void Function(PointerDownEventevent): Signature for listening toPointerDownEvent events.
PointerMoveEventListener= void Function(PointerMoveEventevent): Signature for listening toPointerMoveEvent events.
PointerUpEventListener= void Function(PointerUpEventevent): Signature for listening toPointerUpEvent events.
PopInvokedCallback= void Function(booldidPop): A callback type for informing that a navigation pop has been invoked,whether or not it was handled successfully.
PopInvokedWithResultCallback<T>= void Function(booldidPop,T?result): A callback type for informing that a navigation pop has been invoked,whether or not it was handled successfully.
PopPageCallback=bool Function(Routeroute,dynamicresult): Signature for theNavigator.onPopPage callback.
PopResultCallback<T>= void Function(T?result): A signature for a function that is passed the result of aRoute.
RadioBuilder=Widget Function(BuildContextcontext,ToggleableStateMixin<StatefulWidget>state): Signature forRawRadio.builder.
RawMenuAnchorChildBuilder=Widget Function(BuildContextcontext,MenuControllercontroller,Widget?child): Signature for the builder function used byRawMenuAnchor.builder to buildthe widget that theRawMenuAnchor surrounds.
RawMenuAnchorCloseRequestedCallback= void Function(VoidCallbackhideOverlay): Signature for the callback used byRawMenuAnchor.onCloseRequested tointercept requests to close a menu.
RawMenuAnchorOpenRequestedCallback= void Function(Offset?position,VoidCallbackshowOverlay): Signature for the callback used byRawMenuAnchor.onOpenRequested tointercept requests to open a menu.
RawMenuAnchorOverlayBuilder=Widget Function(BuildContextcontext,RawMenuOverlayInfoinfo): Signature for the builder function used byRawMenuAnchor.overlayBuilder tobuild a menu's overlay.
RebuildDirtyWidgetCallback= void Function(Elemente,boolbuiltOnce): Signature fordebugOnRebuildDirtyWidget implementations.
RegisterServiceExtensionCallback= void Function({requiredServiceExtensionCallbackcallback,requiredStringname}): Signature for a method that registers the service extensioncallback withthe givenname.
RegisterViewFactory= void Function(String,Object(intviewId), {boolisVisible}): Function signature forui_web.platformViewRegistry.registerViewFactory.
RenderConstrainedLayoutBuilder<LayoutInfoType,ChildType extendsRenderObject> =RenderAbstractLayoutBuilderMixin<LayoutInfoType,ChildType>: Generic mixin forRenderObjects created by anAbstractLayoutBuilder withthe the sameLayoutInfoType.
ReorderCallback= void Function(intoldIndex,intnewIndex): A callback used byReorderableList to report that a list item has movedto a new position in the list.
ReorderDragBoundaryProvider=DragBoundaryDelegate<Rect>? Function(BuildContextcontext): Used to provide drag boundaries during drag-and-drop reordering.
ReorderItemProxyDecorator=Widget Function(Widgetchild,intindex,Animation<double>animation): Signature for the builder callback used to decorate the dragging item inReorderableList andSliverReorderableList.
RestorableRouteBuilder<T>=Route<T> Function(BuildContextcontext,Object?arguments): Creates aRoute that is to be added to aNavigator.
RouteCompletionCallback<T>= void Function(Tresult): A callback to handle the result of a completedRoute.
RouteFactory=Route? Function(RouteSettingssettings): Creates a route for the given route settings.
RouteListFactory=List<Route> Function(NavigatorStatenavigator,StringinitialRoute): Creates a series of one or more routes.
RoutePageBuilder=Widget Function(BuildContextcontext,Animation<double>animation,Animation<double>secondaryAnimation): Signature for the function that builds a route's primary contents.Used inPageRouteBuilder andshowGeneralDialog.
RoutePredicate=bool Function(Routeroute): Signature for theNavigator.popUntil predicate argument.
RoutePresentationCallback=String Function(NavigatorStatenavigator,Object?arguments): A callback that given somearguments and anavigator adds a newrestorable route to thatnavigator and returns the opaque ID of thatnew route.
RouteTransitionsBuilder=Widget Function(BuildContextcontext,Animation<double>animation,Animation<double>secondaryAnimation,Widgetchild): Signature for the function that builds a route's transitions.Used inPageRouteBuilder andshowGeneralDialog.
ScrollableWidgetBuilder=Widget Function(BuildContextcontext,ScrollControllerscrollController): The signature of a method that provides aBuildContext andScrollController for building a widget that may overflow the draggableAxis of the containingDraggableScrollableSheet.
ScrollControllerCallback= void Function(ScrollPositionposition): Signature for when aScrollController has added or removed aScrollPosition.
ScrollIncrementCalculator=double Function(ScrollIncrementDetailsdetails): A typedef for a function that can calculate the offset for a type of scrollincrement given aScrollIncrementDetails.
ScrollNotificationCallback= void Function(ScrollNotificationnotification): AScrollNotification listener forScrollNotificationObserver.
ScrollNotificationPredicate=bool Function(ScrollNotificationnotification): A predicate forScrollNotification, used to customize widgets thatlisten to notifications from their children.
SelectableDayPredicate=bool Function(DateTimeday): Signature for predicating dates for enabled date selections.
SelectableRegionContextMenuBuilder=Widget Function(BuildContextcontext,SelectableRegionStateselectableRegionState): Signature for a widget builder that builds a context menu for the givenSelectableRegionState.
SelectionChangedCallback= void Function(TextSelectionselection,SelectionChangedCause?cause): Signature for the callback that reports when the user changes the selection(including the cursor location).
SemanticIndexCallback=int? Function(Widgetwidget,intlocalIndex): A callback which produces a semantic index given a widget and the local index.
SemanticsBuilderCallback=List<CustomPainterSemantics> Function(Sizesize): Signature of the function returned byCustomPainter.semanticsBuilder.
ShaderCallback=Shader Function(Rectbounds): Signature for a function that creates aShader for a givenRect.
ShaderWarmUpImageCallback=bool Function(Imageimage): The signature ofdebugCaptureShaderWarmUpImage.
ShaderWarmUpPictureCallback=bool Function(Picturepicture): The signature ofdebugCaptureShaderWarmUpPicture.
SharedAppDataInitCallback<T>= T Function(): The type of theSharedAppData.getValueinit parameter.
SliverLayoutWidgetBuilder=Widget Function(BuildContextcontext,SliverConstraintsconstraints): The signature of theSliverLayoutBuilder builder function.
StatefulWidgetBuilder=Widget Function(BuildContextcontext,StateSettersetState): Signature for the builder callback used byStatefulBuilder.
StateSetter= void Function(VoidCallbackfn): The signature ofState.setState functions.
TapBehaviorButtonBuilder=Widget Function(BuildContextcontext, {requiredVoidCallbackonPressed,requiredboolselectionOnTapEnabled,requiredStringsemanticsLabel}): Signature for the builder callback used byWidgetInspector.tapBehaviorButtonBuilder.
TapRegionCallback= void Function(PointerDownEventevent): Signature for a callback called for aPointerDownEvent relative to aTapRegion.
TapRegionUpCallback= void Function(PointerUpEventevent): Signature for a callback called for aPointerUpEvent relative to aTapRegion.
ToolbarBuilder=Widget Function(BuildContextcontext,Widgetchild): The type for a Function that builds a toolbar's container with the givenchild.
TransformCallback=Matrix4 Function(doubleanimationValue): Signature for the callback toMatrixTransition.onTransform.
TransitionBuilder=Widget Function(BuildContextcontext,Widget?child): A builder that builds a widget given a child.
TraversalRequestFocusCallback= void Function(FocusNodenode, {double?alignment,ScrollPositionAlignmentPolicy?alignmentPolicy,Curve?curve,Duration?duration}): Signature for the callback that's called when a traversal policyrequests focus.
TreeSliverNodeBuilder=Widget Function(BuildContextcontext,TreeSliverNode<Object?>node,AnimationStyleanimationStyle): Signature for a function that creates aWidget to represent the givenTreeSliverNode in theTreeSliver.
TreeSliverNodeCallback= void Function(TreeSliverNode<Object?>node): Signature for a function that is called when aTreeSliverNode is toggled,changing its expanded state.
TreeSliverRowExtentBuilder=double Function(TreeSliverNode<Object?>node,SliverLayoutDimensionsdimensions): Signature for a function that returns an extent for the givenTreeSliverNode in theTreeSliver.
TweenConstructor<T extendsObject>=Tween<T> Function(TtargetValue): Signature for aTween factory.
TweenVisitor<T extendsObject>=Tween<T>? Function(Tween<T>?tween,TtargetValue,TweenConstructor<T>constructor): Signature for callbacks passed toImplicitlyAnimatedWidgetState.forEachTween.
TwoDimensionalIndexedWidgetBuilder=Widget? Function(BuildContextcontext,ChildVicinityvicinity): Signature for a function that creates a widget for a givenChildVicinity,e.g., in aTwoDimensionalScrollView, but may return null.
TwoDimensionalViewportBuilder=Widget Function(BuildContextcontext,ViewportOffsetverticalPosition,ViewportOffsethorizontalPosition): Signature used byTwoDimensionalScrollable to build the viewport throughwhich the scrollable content is displayed.
ValueChanged<T>= void Function(Tvalue): Signature for callbacks that report that an underlying value has changed.
ValueGetter<T>= T Function(): Signature for callbacks that are to report a value on demand.
ValueListenableTransformer<T>= T Function(T): Signature for method used to transform values inAnimation.fromValueListenable.
ValueSetter<T>= void Function(Tvalue): Signature for callbacks that report that a value has been set.
ValueWidgetBuilder<T>=Widget Function(BuildContextcontext,Tvalue,Widget?child): Builds aWidget when given a concrete value of aValueListenable<T>.
ViewportBuilder=Widget Function(BuildContextcontext,ViewportOffsetposition): Signature used byScrollable to build the viewport through which thescrollable content is displayed.
VoidCallback= void Function(): Signature of callbacks that have no arguments and return no data.
WidgetBuilder=Widget Function(BuildContextcontext): Signature for a function that creates a widget, e.g.StatelessWidget.buildorState.build.
WidgetPropertyResolver<T>= T Function(Set<WidgetState>states): Signature for the function that returns a value of typeT based on a givenset of states.
WidgetStateMap<T> =Map<WidgetStatesConstraint,T>: AMap used to resolve to a single value of typeT based onthe current set of Widget states.
WillPopCallback=Future<bool> Function(): Signature for a callback that verifies that it's OK to callNavigator.pop.

Exceptions / Errors

FlutterError: Error class used to report Flutter-specific assertion failures andcontract violations.
NetworkImageLoadException: The exception thrown when the HTTP request to load a network image fails.
TickerCanceled: Exception thrown byTicker objects on theTickerFuture.orCancel futurewhen the ticker is canceled.

Flutter
widgets.dart

Movatterモバイル変換

widgets library

Classes

Enums

Mixins

Extension Types

Extensions

Constants

Properties

Functions

Typedefs

Exceptions / Errors

Flutterpackage

widgets library