updateShouldNotify method

@override bool updateShouldNotify(covariant FormControlScope oldWidget)

Whether replacement of this widget should rebuild its readers.

Ordinary values use ==; listenable values use identity so readers see a replacement source even if it compares equal. A subclass may compare a narrower field. Owned scopes retain their object across rebuilds. Notifications from a Listenable always reach readers independently.

Implementation

@override
bool updateShouldNotify(FormControlScope oldWidget) =>
    error != oldWidget.error || super.updateShouldNotify(oldWidget);