toSignal method

Signal<T> toSignal({ String? debugLabel, bool autoDispose = false, })

Bi-directional Signal and ValueNotifier Interoperability

Converted ValueNotifier objects become mutable Signal instances. Setting the value on the signal or the notifier automatically propagates the update to the other.

The subscription is fully memory-safe and automatically unsubscribed when the signal is disposed.

Example: Converting a ValueNotifier to a Signal

final notifier = ValueNotifier(10);
final signal = notifier.toSignal();

signal.value = 20;
print(notifier.value); // 20

notifier.value = 30;
print(signal.value); // 30

Example: Converting a Signal to a ValueNotifier

To bridge back to a standard ValueNotifier for Flutter compatibility:

final signal = Signal(10);
final notifier = signal.toValueNotifier();

@link https://dartsignals.dev/flutter/value-notifier

Implementation

Signal<T> toSignal({
  String? debugLabel,
  bool autoDispose = false,
}) {
  bool? self;
  final target = signal<T>(
    value,
    debugLabel: debugLabel,
    autoDispose: autoDispose,
  );

  void updater() {
    if (self == false) {
      // Update from signal
    } else {
      // Normal flow
      self = true;
      target.value = value;
      self = null;
    }
  }

  addListener(updater);
  target.onDispose(() => removeListener(updater));

  target.subscribe((val) {
    if (self == true) {
      // Update from value notifier
    } else {
      // Normal flow
      self = false;
      value = val;
      self = null;
    }
  });

  return target;
}