SignalStatefulWidget class abstract

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

Subclasses of SignalStatefulWidget establish a dynamic reactive context directly at the Flutter element layer. Any signal value accessed synchronously inside State's build method is implicitly tracked and subscribed to. When a signal changes, only that element is rebuilt.

This offers a clean, Javascript-style reactivity experience while retaining all stateful lifecycles. It is the modern, highly recommended replacement for the legacy, deprecated SignalsMixin.

Implicit Reactivity Example (Stateful)

class CounterControl extends SignalStatefulWidget {
  const CounterControl({super.key});

  @override
  State<CounterControl> createState() => _CounterControlState();
}

class _CounterControlState extends State<CounterControl> {
  // Create state signals directly inside the State object:
  final count = signal(0);

  @override
  Widget build(BuildContext context) {
    // Automatically tracked on access and safely unsubscribed on unmount:
    return ElevatedButton(
      onPressed: () => count.value++,
      child: Text('Count: ${count.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

StatefulWidgetConvertWidgetExtension

Constructors

SignalStatefulWidget({Key? key}): Constructor for SignalStatefulWidget.
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

createElement() → StatefulElement: Creates a StatefulElement to manage this widget's location in the tree.
override
createState() → State<StatefulWidget>: Creates the mutable state for this widget at a given location in the tree.
inherited
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
toSignalStatefulWidget() → SignalStatefulWidget: Available on StatefulWidget, provided by the StatefulWidgetConvertWidgetExtension extension
Converts this StatefulWidget to a SignalStatefulWidget.
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