how to enable scrolling when ListView widget reach at top in flutter - flutter

Question

To explain what I want I have created a simple demo file
Here I have 4 container,
What I want is, when I scroll up ,all three container( RED, GREEN and listview) should be scrolled up and when listview reach at top (below welcome container) its scrolling should be start...
class HomeScreen extends StatelessWidget {
HomeScreen({Key? key}) : super(key: key);
List<String> mydata = [];
#override
Widget build(BuildContext context) {
return Scaffold(
body: SafeArea(
child: Column(
children: [
//this welcome container should be fixed at top
Container(height: 50, child: Center(child: Text('Welcome'))),
Container(
height: 100,
color: Colors.red,
),
Container(
height: 200,
color: Colors.green,
),
Expanded(
child: ListView.builder(
itemCount: mydata.length,
itemBuilder: (context, index) {
return ListTile(
title: Text(mydata[index]),
leading: CircleAvatar(),
);
}))
],
),
),
);
}
}

Answer 1

You can increase the itemCount by two.
body: SafeArea(
child: Column(
children: [
Container(height: 50, child: Center(child: Text('Welcome'))),
Expanded(
child: ListView.builder(
itemCount: mydata.length + 2,
itemBuilder: (context, index) {
if (index == 0) {
return Container(
height: 100,
color: Colors.red,
);
}
if (index == 1) { // you can just merge it with if like `index<2`, then use condition
return Container(
height: 200,
color: Colors.green,
);
}
return ListTile(
title: Text(mydata[index - 2]),
leading: CircleAvatar(),
);
}))
],
),
),
Also I will suggest you to check CustomScrolView.