descartar aleteo del teclado
// The correct way of closing the keyboard is
FocusScope.of(context).unfocus();
Flutter Guy
// The correct way of closing the keyboard is
FocusScope.of(context).unfocus();CustomScrollView(
slivers: [
SliverFillRemaining(
hasScrollBody: false,
child: Column(
children: <Widget>[
const Text('Header'),
Expanded(child: Container(color: Colors.red)),
const Text('Footer'),
],
),
),
],
)