Flutter layout issue about Flexible - layout

Question

I am developing a flutter app, but it show error when I run the app.
I don't understand what is the problem. I think I mix up the logic of how the widget expand in layout.
Please kindly help to solve this issue.
error message:
flutter: The following assertion was thrown during performResize():
flutter: Vertical viewport was given unbounded height.
Viewports expand in the scrolling direction to fill their container.In this case, a vertical
viewport was given an unlimited amount of vertical space in which to expand. This situation
typically happens when a scrollable widget is nested inside another scrollable widget.
Here with my code:
body: Container(
child: Flexible(
child: FirebaseAnimatedList(
query: databaseReference,
itemBuilder: (_, DataSnapshot snapshot,
Animation<double> animation,
int index) {
return new Card(
color: Colors.black38,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
ListTile(
leading: IconButton(
icon: Icon(Icons.format_list_bulleted),
color: Colors.blueAccent,
splashColor: Colors.greenAccent,
onPressed: () {
// Perform some action
debugPrint('button ok');
},
),
title: Text(shopList[index].shopName),
subtitle: Text(shopList[index].address),
),
Container(
child: Flexible(
child: Form(
key: formShopKey,
child: ListView(
children: <Widget>[
ListTile(
leading: Icon(
Icons.money_off,
color: Colors.white,
),
title: TextFormField(
maxLength: 100,
initialValue: "",
maxLines: 3,
//onSaved: (val) => booking.seafoodRequest = val,
//validator: (val) => val == "" ? val : null,
decoration: new InputDecoration(
),
),
),
],
),
),
),
),
ButtonTheme.bar(
// make buttons use the appropriate styles for cards
child: new ButtonBar(
children: <Widget>[
new FlatButton(
child: const Text('BUY TICKETS'),
onPressed: () {
/* ... */
},
),
new FlatButton(
child: const Text('LISTEN'),
onPressed: () {
/* ... */
},
),
],
),
),
],
),
);
},
),
),
);
[1]: https://i.stack.imgur.com/5vAsv.png
[2]: https://i.stack.imgur.com/LuZEl.png

Answer 1

I had to fill in a few gaps but the below should build for you. I also swapped FirebaseAnimatedList with a regular AnimatedList to get it to build. You can compare and adjust the layout.
import 'package:flutter/material.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(title: 'Flutter Demo'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
#override
Widget build(BuildContext context) {
return new Scaffold(
body: Column(
mainAxisSize: MainAxisSize.max,
children: <Widget>[
Expanded(
child: AnimatedList(
initialItemCount: 10,
itemBuilder: (BuildContext context, int index,
Animation<double> animation) {
return new Card(
color: Colors.black38,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
ListTile(
leading: IconButton(
icon: Icon(Icons.format_list_bulleted),
color: Colors.blueAccent,
splashColor: Colors.greenAccent,
onPressed: () {
// Perform some action
debugPrint('button ok');
},
),
title: Text('Name'),
subtitle: Text('Address'),
),
Container(
constraints: BoxConstraints(
minHeight: 100.0,
maxHeight: 200.0,
),
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Expanded(
child: Form(
child: ListView(
children: <Widget>[
ListTile(
leading: Icon(
Icons.money_off,
color: Colors.white,
),
title: TextFormField(
maxLength: 100,
initialValue: "",
maxLines: 3,
//onSaved: (val) => booking.seafoodRequest = val,
//validator: (val) => val == "" ? val : null,
decoration: new InputDecoration(),
),
),
],
),
),
),
],
),
),
ButtonTheme.bar(
// make buttons use the appropriate styles for cards
child: new ButtonBar(
children: <Widget>[
new FlatButton(
child: const Text('BUY TICKETS'),
onPressed: () {
/* ... */
},
),
new FlatButton(
child: const Text('LISTEN'),
onPressed: () {
/* ... */
},
),
],
),
),
],
),
);
},
),
),
],
),
);
}
}