How to put a floating widget in flutter? - flutter

Question

What I want to do is make a TextField stay in the same position by scrolling down the screen. I want to know if there is a way to do this?
This is the TextField that I want to be floating:
This is the code, the CardWidget are just cards and searchInput is the textField:
class RouteListPage extends StatefulWidget {
#override
_RouteListPageState createState() => _RouteListPageState();
}
class _RouteListPageState extends State<RouteListPage> {
TextEditingController searchController = new TextEditingController();
#override
Widget build(BuildContext context) {
final _screenSize = MediaQuery.of(context).size;
return Scaffold(
body: SingleChildScrollView(
child: Column(
children: <Widget>[
searchInput(),
CardWidget(),
CardWidget(),
CardWidget(),
CardWidget(),
SizedBox(height: 25.0)
],
),
),
);
}
Widget searchInput(){
return Container(
margin: EdgeInsets.symmetric(horizontal: 24, vertical: 25.0),
padding: EdgeInsets.symmetric(horizontal: 24),
decoration: BoxDecoration(
color: Color(0xfff6f6f6),
borderRadius: BorderRadius.circular(30),
boxShadow: <BoxShadow>[
BoxShadow(
color: Colors.black45,
offset: Offset(0.0, 2.0),
blurRadius: 10.0,
),
],
),
child: Row(
children: <Widget>[
Expanded(
child: TextField(
controller: searchController,
decoration: InputDecoration(
hintText: "Buscar rutas",
hintStyle: TextStyle(fontFamily: "WorkSansSemiBold", fontSize: 16.0),
border: InputBorder.none
),
)
),
InkWell(
onTap: () {},
child: Container(
child: Icon(Icons.search, color: Tema.Colors.loginGradientEnd, size: 28.0)
)
)
],
),
);
}
}

Answer 1

You can use a Stack widget and have the scrolling widget below the TextField widget. Use the Positioned widget to control the position of searchInput()
Your build method will change to this:
#override
Widget build(BuildContext context) {
final _screenSize = MediaQuery.of(context).size;
return Scaffold(
body: Stack(
children: <Widget>[
SingleChildScrollView(
child: Column(
children: <Widget>[
CardWidget(),
CardWidget(),
CardWidget(),
CardWidget(),
SizedBox(height: 25.0)
],
),
),
Positioned(
top: 24.0,
left: 0.0,
right: 0.0,
child: searchInput(),
)
],
),
);
}

Answer 2

Instead of SingleChildScrollView try using this
Stack(
children: <Widget>[
searchInput(),
ListView(
children: <Widget>[
CardWidget(),
CardWidget(),
CardWidget()
],
)
],
),

Answer 3

Use a Stack and add your scrollview and the input as children:
Stack(
children: [
SingleChildScrollView(),
searchInput(),
],
)