SignalWidget class abstract

A reactive StatelessWidget that implicitly tracks and rebuilds on signal changes.

SignalWidget establishes a dynamic reactive context directly at the Flutter element layer. Any signal accessed via .value inside the build method is implicitly tracked and subscribed to. When any of these signals mutate, only this widget is rebuilt.

This offers a clean, Javascript-style reactivity experience without needing manual builder widgets (like SignalBuilder) or deprecated context watch extensions.

Implicit Reactivity Example (Stateless)

final username = signal('Rody');
final status = signal('Online');

class UserProfileView extends SignalWidget {
  const UserProfileView({super.key});

  @override
  Widget build(BuildContext context) {
    // 'username' and 'status' are implicitly tracked on access:
    return Column(
      children: [
        Text('Name: ${username.value}'),
        Text('Status: ${status.value}'),
      ],
    );
  }
}

Important

Only signals accessed synchronously during the execution of the build method are tracked. Signals read inside async callbacks, listeners, or deferred tasks are not subscribed to.

Inheritance

Available extensions

StatelessWidgetConvertWidgetExtension

Constructors

SignalWidget({Key? key}): Constructor for SignalWidget.
const

Properties

hashCode → int: The hash code for this object.
no setterinherited
key → Key?: Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited

Methods

build(BuildContext context) → Widget: Describes the part of the user interface represented by this widget.
inherited
createElement() → StatelessElement: Creates a StatelessElement to manage this widget's location in the tree.
override
debugDescribeChildren() → List<DiagnosticsNode>: Returns a list of DiagnosticsNode objects describing this node's children.
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void: Add additional properties associated with the node.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent 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
toSignalWidget() → SignalWidget: Available on StatelessWidget, provided by the StatelessWidgetConvertWidgetExtension extension
Converts this StatelessWidget to a SignalWidget.
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String: A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug, int wrapWidth = 65}) → 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

Operators

operator ==(Object other) → bool: The equality operator.
inherited