watch<Res> method

@override Res watch<Res>(ProviderListenable<Res> target)

Returns the value exposed by a provider and rebuild the widget when that value changes.

See also:

• ProviderBase.select, which allows a widget to filter rebuilds by observing only the properties.
• listen, to react to changes on a provider, such as for showing modals.

Implementation

@override
Res watch<Res>(ProviderListenable<Res> target) {
  return _dependencies.putIfAbsent(target, () {
    final oldDependency = _oldDependencies?.remove(target);

    if (oldDependency != null) {
      return oldDependency;
    }

    return _container.listen<Res>(
      target,
      (_, __) => markNeedsBuild(),
    );
  }).read() as Res;
}