Semantics class Null safety

A widget that annotates the widget tree with a description of the meaning of the widgets.

Used by accessibility tools, search engines, and other semantic analysis software to determine the meaning of the application.

See also:

Inheritance
Annotations

Constructors

Semantics({Key? key, Widget? child, bool container = false, bool explicitChildNodes = false, bool excludeSemantics = false, bool? enabled, bool? checked, bool? selected, bool? toggled, bool? button, bool? slider, bool? keyboardKey, bool? link, bool? header, bool? textField, bool? readOnly, bool? focusable, bool? focused, bool? inMutuallyExclusiveGroup, bool? obscured, bool? multiline, bool? scopesRoute, bool? namesRoute, bool? hidden, bool? image, bool? liveRegion, int? maxValueLength, int? currentValueLength, String? label, AttributedString? attributedLabel, String? value, AttributedString? attributedValue, String? increasedValue, AttributedString? attributedIncreasedValue, String? decreasedValue, AttributedString? attributedDecreasedValue, String? hint, AttributedString? attributedHint, String? tooltip, String? onTapHint, String? onLongPressHint, TextDirection? textDirection, SemanticsSortKey? sortKey, SemanticsTag? tagForChildren, VoidCallback? onTap, VoidCallback? onLongPress, VoidCallback? onScrollLeft, VoidCallback? onScrollRight, VoidCallback? onScrollUp, VoidCallback? onScrollDown, VoidCallback? onIncrease, VoidCallback? onDecrease, VoidCallback? onCopy, VoidCallback? onCut, VoidCallback? onPaste, VoidCallback? onDismiss, MoveCursorHandler? onMoveCursorForwardByCharacter, MoveCursorHandler? onMoveCursorBackwardByCharacter, SetSelectionHandler? onSetSelection, SetTextHandler? onSetText, VoidCallback? onDidGainAccessibilityFocus, VoidCallback? onDidLoseAccessibilityFocus, Map<CustomSemanticsAction, VoidCallback>? customSemanticsActions})
Creates a semantic annotation.
Semantics.fromProperties({Key? key, Widget? child, bool container = false, bool explicitChildNodes = false, bool excludeSemantics = false, required SemanticsProperties properties})
Creates a semantic annotation using SemanticsProperties.
const

Properties

child Widget?
The widget below this widget in the tree.
finalinherited
container bool
If container is true, this widget will introduce a new node in the semantics tree. Otherwise, the semantics will be merged with the semantics of any ancestors (if the ancestor allows that).
final
excludeSemantics bool
Whether to replace all child semantics with this node.
final
explicitChildNodes bool
Whether descendants of this widget are allowed to add semantic information to the SemanticsNode annotated by this widget.
final
hashCode int
The hash code for this object.
nonVirtual">@nonVirtualread-onlyinherited
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
properties SemanticsProperties
Contains properties used by assistive technologies to make the application more accessible.
final
runtimeType Type
A representation of the runtime type of the object.
read-onlyinherited

Methods

createElement() SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
createRenderObject(BuildContext context) RenderSemanticsAnnotations
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.
override
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
protected">@protectedinherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
override
didUnmountRenderObject(covariant RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
protected">@protectedinherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) String
A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object.
inherited
toStringShort() String
A short, textual description of this widget.
inherited
updateRenderObject(BuildContext context, covariant RenderSemanticsAnnotations renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject.
override

Operators

operator ==(Object other) bool
The equality operator.
nonVirtual">@nonVirtualinherited