Handle listview item height? - flutter

So i have this script which is build a listview
class NewProductsLists extends StatelessWidget {
final List<NewProducts> newlist;
NewProductsLists({Key key, this.newlist}) : super(key: key);
final formatCurrency =
new NumberFormat.simpleCurrency(locale: "id", decimalDigits: 2);
#override
Widget build(BuildContext context) {
return Expanded(
child: ListView.builder(
itemCount: newlist.length,
shrinkWrap: true,
scrollDirection: Axis.horizontal,
itemBuilder: (BuildContext context, int index) {
return GestureDetector(
onTap: () {
print("Product detail");
},
child: Card(
child: Container(
width: MediaQuery.of(context).size.width * 0.50,
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Image.network(
Configuration.url +
"assets/app_assets/" +
newlist[index].productImage,
width: 90,
height: 90,
filterQuality: FilterQuality.low),
ListTile(
title: Center(
child: Text(
newlist[index].productName,
style: TextStyle(fontSize: 18),
)),
subtitle: Center(
child: Text(
formatCurrency.format(
int.parse(newlist[index].productPrice)),
style: TextStyle(color: Colors.red, fontSize: 15),
)),
),
],
)),
),
);
}));
}
}
and the result looks like this
[
As you can see the card is expanding so hard. I know it is because the Expanded widget. Is it possible to make the card wrap_content ?

For horizontal list view needs fixed height if its not going to be vertical scrollable view you can use Expanded widget with varying flex to get it working.
Working build widget by using expanded widget.
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
centerTitle: false,
title: const Text('November'),
),
body: new Container(
child: Column(
children: <Widget>[
new Expanded(flex: 1,child: new Container(color: Colors.grey[300],),),
Expanded(flex: 2,
child: ListView.builder(
itemCount: 10,
shrinkWrap: true,
scrollDirection: Axis.horizontal,
itemBuilder: (BuildContext context, int index) {
return GestureDetector(
onTap: () {
print("Product detail");
},
child: Card(
child: Container(
width: MediaQuery.of(context).size.width * 0.50,
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Image.network(
'https://homepages.cae.wisc.edu/~ece533/images/watch.png',
width: 90,
height: 90,
filterQuality: FilterQuality.low),
ListTile(
title: Center(
child: Text(
'item Name ${index}',
style: TextStyle(fontSize: 18),
)),
subtitle: Center(
child: Text(
'\$10',
style: TextStyle(
color: Colors.red, fontSize: 15),
)),
),
],
)),
),
);
}),
),
new Expanded(flex: 3,child: new Container(color: Colors.amber[100],),),
],
)));
}
Result screen
Let me know if it suits your requirement.

Related

Vertical and Horizontal Coordinated Scrolling of Independent Lists

I have joined tables of data that I need to scroll together on both horizontal and vertical axis, with heading First Row that should not scroll with vertical data, but should scroll with horizontal.
You can see from my video that my simplified example below will scroll as desired vertically, but the rows, being independent do not scroll horizontally together as needed. The question is how to scroll each independent list horizontally together without losing the vertical functionality. The number of rows and columns is variable and can be quite large. My example code below is simplified to illustrate the behavior.
The below is a complete project example that can be cut and pasted into a dartpad flutter project or just click here: https://dartpad.dev/?id=6c4ea40ceee87ce9de4bcfe38ba0b750
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.light(),
debugShowCheckedModeBanner: false,
home: Scaffold(
body: MyWidget(),
),
);
}
}
class MyWidget extends StatelessWidget {
#override
Widget build(BuildContext context) {
List listDates = ['Jan', 'Feb', 'Mar', 'Apr'];
Map<String, List> all = {
'Todd': [1,2,3,4],
'Mary': [5,6,7,8],
'Henry': [9,10,11,12],
};
List<String> names = [];
all.forEach((key,value) {
names.add(key);
});
return Column(
children: [
SizedBox(
height: 200,
child: Row(
crossAxisAlignment: CrossAxisAlignment.end,
children: [
const SizedBox(
height: 200,
width: 200,
),
Expanded(
child: ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: listDates.length,
itemBuilder: (context, index) {
return Column(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.end,
crossAxisAlignment: CrossAxisAlignment.start,
children: [
SizedBox(
width: 200,
child: Center(
child: Text(
listDates[index],
style: const TextStyle(
fontWeight: FontWeight.w600,
),
maxLines: 1,
textAlign: TextAlign.center,
),
),
),
],
);
},),
),
],
),
),
Expanded(
child: ListView.builder(
itemCount: 3,
itemBuilder: (context, index) {
return Container(
decoration: BoxDecoration(
color: index.isOdd ? Colors.blue.withOpacity(.2) : Colors.grey.withOpacity(.2),
),
child: SizedBox(
height: 200,
width: double.infinity,
child: Row(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisAlignment: MainAxisAlignment.start,
mainAxisSize: MainAxisSize.max,
children: [
SizedBox(
width: 200,
height: 200,
child: Padding(
padding: const EdgeInsets.all(4.0),
child: Text(
names[index],
style: const TextStyle(
fontWeight: FontWeight.w500,
),
),
),
),
Expanded(
child: ListView.builder(
scrollDirection: Axis.horizontal,
itemCount: listDates.length,
itemBuilder: (context, index2) {
List ints = all[names[index]]!;
return SizedBox(
width: 200,
child: Center(
child: Text(
ints[index2].toString(),
style: const TextStyle(
fontWeight: FontWeight.w600,
),
maxLines: 1,
textAlign: TextAlign.center,
),
),
);
},
),
),
],
),
),
);
},
),),
],
);
}
}

How to sort functionality & filter data got from restapi

starting my carrer in flutter development for 2 months
while doing this project based in flutter,i get data from rest api with bloc state management & listed it with listvieww builder, but want add sort & filter functionality to it,, can you please explain how to do with an example, excepting valuable suggestions from you guys
search and filter functionilty
class Upcoming extends StatefulWidget {
Upcoming({Key? key}) : super(key: key);
#override
State<Upcoming> createState() => _UpcomingState();
}
class _UpcomingState extends State<Upcoming> {
#override
Widget build(BuildContext context) {
return BlocBuilder<MOdelBloc, MOdelState>(
builder: (context, state) {
if (state is MOdelInitial) {
context.read<MOdelBloc>().add(LoadEVENT());
return const Center(
child: CircularProgressIndicator(),
);
} else if (state is ModelLoading) {
return const Center(
child: CircularProgressIndicator(),
);
} else if (state is ModelLoadedstate) {
return buildupcoming(state.fakestore);
} else if (state is ErrorSatte) {
return const Center(
child: Text('errorstate'),
);
}
return const Center(child: Text('error'));
},
);
}
}
Widget buildupcoming(List<CryptoCurrency> currency) {
return Scaffold(
appBar: AppBar(
backgroundColor: Colors.yellow.shade400,
leading: const Icon(
Icons.portrait_rounded,
),
title: const Center(
child: Text(
'Upcoming Matches',
style: TextStyle(fontWeight: FontWeight.bold),
),
),
actions: const [
Icon(
Icons.headset,
),
SizedBox(
width: 5,
),
Icon(Icons.message)
],
),
body: SingleChildScrollView(
scrollDirection: Axis.vertical,
child: Container(
height: double.maxFinite,
margin: const EdgeInsets.all(10),
child:
Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
ElevatedButton(
onPressed: () {}, child: const Text('CRICKET')),
const SizedBox(
width: 15,
),
ElevatedButton(
onPressed: () {},
child: const Icon(Icons.sports_football))
],
),
const SizedBox(
height: 10,
),
Row(
children: const [
TextWidget(text: 'My Rooms', size: 20),
Spacer(),
Text(
'View all',
style: TextStyle(color: Colors.black45),
)
],
),
const SizedBox(
height: 5,
),
Container(
height: 170,
child: PageView.builder(
scrollDirection: Axis.horizontal,
itemCount: 3,
itemBuilder: (context, index) {
return Container(
margin: const EdgeInsets.only(left: 5),
child: Column(children: [
SliderCARD(
text1: currency[2].fullname.toString(),
text2: currency[3].fullname,
minitext1: currency[2].price.toString(),
minitext2: currency[4].price.toString(),
color: Colors.indigo,
height: 100,
),
Row(children: [IconButton(onPressed: ( ){},
icon: Icon(Icons.arrow_back)),IconButton(onPressed: (){}, icon: Icon(Icons.arrow_back_outlined))],)]));
})),
ListView.builder(
physics:const NeverScrollableScrollPhysics(),
shrinkWrap: true,
itemCount: currency.length,
itemBuilder: (context, index) {
final CryptoCurrency cryptoCurrency = currency[index];
return Container(
margin: const EdgeInsets.only(bottom: 10),
height: 100,
child: SliderCARD(
text1: cryptoCurrency.fullname,
text2: currency[3].fullname,
minitext1: cryptoCurrency.price.toString(),
minitext2: currency[4].price.toString(),
color: Colors.white,
height: 100,
));
})
])),
));
}

Flutter: Errors when wrapping Layoutbuilder and Text in Column

I currently have a listview with an alphabet scroller on the side. I'm trying to add a searchbox to the top, but whenever I wrap something in a column, I get errors.
Using the current code, ListView inside Stack is throwing Vertical viewport was given unbounded height.
When I remove the column and Text('TestString'), my code works fine. I have tried adding an Expandable around the ListView.Builder but this also doesn't seem to solve it.
#override
Widget build(BuildContext context) {
height = MediaQuery.of(context).size.height;
return Scaffold(
appBar: AppBar(
title: Text(widget.title,
style: TextStyle(
fontSize: 20.0,
color: Colors.white,
fontWeight: FontWeight.bold)),
centerTitle: true,
),
body: Column(
children: [
Text('TestString'),
new LayoutBuilder(
builder: (context, constraints) {
return new Stack(children: [
//Causes the current issue
ListView.builder(
itemCount: exampleList.length,
controller: _controller,
itemExtent: _itemsizeheight,
itemBuilder: (context, position) {
return Padding(
padding: const EdgeInsets.only(right: 32.0),
child: Card(
child: Padding(
padding: const EdgeInsets.all(16.0),
child: Text(
exampleList[position],
style: TextStyle(fontSize: 20.0),
),
),
));
},
),
Positioned(
right: _marginRight,
top: _offsetContainer,
child: _getSpeechBubble()),
Align(
alignment: Alignment.centerRight,
child: GestureDetector(
onTapDown: (details) {
_onTapDown(details);
},
child: GestureDetector(
onVerticalDragUpdate: _onVerticalDragUpdate,
onVerticalDragStart: _onVerticalDragStart,
onVerticalDragEnd: (details) {
setState(() {
isPressed = false;
});
},
child: Container(
//height: 20.0 * 26,
color: Colors.transparent,
child: new Column(
mainAxisAlignment: MainAxisAlignment.center,
children: []..addAll(
new List.generate(_alphabet.length,
(index) => _getAlphabetItem(index)),
),
),
),
),
),
),
]);
},
),
],
),
);
}
_getSpeechBubble() {
return isPressed
? new SpeechBubble(
nipLocation: NipLocation.RIGHT,
child: Row(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Container(
width: 30,
child: Center(
child: Text(
"${_text ?? "${_alphabet.first}"}",
style: TextStyle(
color: Colors.white,
fontSize: 18.0,
),
),
),
),
],
),
)
: SizedBox.shrink();
}
ValueGetter? callback(int value) {}
_getAlphabetItem(int index) {
return new Expanded(
child: new Container(
width: 40,
height: 20,
alignment: Alignment.center,
child: new Text(
_alphabet[index],
style: (index == posSelected)
? new TextStyle(fontSize: 16, fontWeight: FontWeight.w700)
: new TextStyle(fontSize: 12, fontWeight: FontWeight.w400),
),
),
);
}
You can wrap your LayoutBuilder() with Expanded() like this and it won't show an error.
return Container(
child: Column(
children: [
Text("Header"),
Expanded(
child: ListView.builder(
itemCount:50,
itemBuilder: (BuildContext context, int index) {
return Text("List Item $index");
},
),
),
Text("Footer"),
],
),
);
You can try the code here

A RenderFlex overflowed by 1443 pixels on the bottom

I am trying to make it scrollable...enter image description here For some reason its not not scrolling and i tried adding singleChildScrollview still not working.... Pls look at the picture to understand better... so i posted the full code so that you guys can help me better... This was the error i got "Consider applying a flex factor (e.g. using an Expanded widget) to force the children of the RenderFlex to fit within the available space instead of being sized to their natural size. This is considered an error condition because it indicates that there is content that cannot be seen. If the content is legitimately bigger than the available space, consider clipping it with a ClipRect widget before putting it in the flex, or using a scrollable container rather than a Flex, like a ListView."
import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/material.dart';
import 'package:memoryblog/helper/authenticate.dart';
import 'package:memoryblog/services/auth.dart';
import 'package:memoryblog/services/database.dart';
import 'package:memoryblog/views/create_blog.dart';
class MemoryRoom extends StatefulWidget {
#override
_MemoryRoomState createState() => _MemoryRoomState();
}
class _MemoryRoomState extends State<MemoryRoom> {
AuthMethod authMethod = new AuthMethod();
DatabaseMethods databaseMethod = new DatabaseMethods();
Stream blogsStream;
Widget BlogsList(){
return Container(
child: blogsStream != null ? Column(
children: <Widget>[
StreamBuilder(
stream: blogsStream,
builder: (context, snapshot){
if(snapshot.data == null) return CircularProgressIndicator();
return ListView.builder(
padding: EdgeInsets.symmetric(horizontal: 16),
itemCount: snapshot.data.documents.length,
shrinkWrap: true,
itemBuilder: (context, index){
return BlogsTile(
authorName: snapshot.data.documents[index].data['memoryName'],
title: snapshot.data.documents[index].data['title'],
description: snapshot.data.documents[index].data['desc'],
imgUrl: snapshot.data.documents[index].data['imgUrl'],
);
}
);
},
)
],
) : Container(
alignment: Alignment.center,
child: CircularProgressIndicator(),
)
);
}
#override
void initState() {
// TODO: implement initState
databaseMethod.getData().then((result){
setState(() {
blogsStream = result;
});
});
super.initState();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Row(
children: <Widget>[
Text(
"Memory"
),
Text(
"Blog",
style: TextStyle(
color: Colors.blue
),
)
],
),
backgroundColor: Colors.transparent,
elevation: 0.0,
actions: <Widget>[
GestureDetector(
onTap: (){
authMethod.signOut();
Navigator.pushReplacement(context, MaterialPageRoute(
builder: (context) => Authenticate()
));
},
child: Container(
padding: EdgeInsets.symmetric(horizontal: 16),
child: Icon(Icons.power_settings_new)),
)
],
),
body: BlogsList(),
floatingActionButton: Container(
padding: EdgeInsets.symmetric(vertical: 20),
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
FloatingActionButton(
onPressed: (){
Navigator.push(context, MaterialPageRoute(
builder: (context) => CreateBlog()
));
},
child: Icon(Icons.add),
)
],
),
),
);
}
}
class BlogsTile extends StatelessWidget {
String imgUrl, title, description, authorName;
BlogsTile({#required this.imgUrl, #required this.title, #required this.description, #required this.authorName,});
#override
Widget build(BuildContext context) {
return Container(
margin: EdgeInsets.only(bottom: 16),
height: 170,
child: Stack(
children: <Widget>[
ClipRRect(
borderRadius: BorderRadius.circular(6),
child: CachedNetworkImage(
imageUrl: imgUrl,
width: MediaQuery.of(context).size.width,
fit: BoxFit.cover,
)
),
Container(
height: 170,
decoration: BoxDecoration(
color: Colors.black45.withOpacity(0.3),
borderRadius: BorderRadius.circular(6)
),
),
Container(
width: MediaQuery.of(context).size.width,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Text(
title,
textAlign: TextAlign.center,
style: TextStyle(fontSize: 25, fontWeight: FontWeight.w500),
),
SizedBox(height: 4,),
Text(
description,
textAlign: TextAlign.center,
style: TextStyle(fontSize: 17, fontWeight: FontWeight.w400),
),
SizedBox(height: 4,),
Text(authorName)
],
),
)
],
),
);
}
}
Use ListView in place of the column. OR
Wrap Column with SingleChildScrollView
return Container(
child: blogsStream != null
? ListView(
children: <Widget>[
StreamBuilder(
stream: blogsStream,
builder: (context, snapshot) {
if (snapshot.data == null) return CircularProgressIndicator();
return ListView.builder(
padding: EdgeInsets.symmetric(horizontal: 16),
itemCount: snapshot.data.documents.length,
shrinkWrap: true,
itemBuilder: (context, index) {
return BlogsTile(
authorName:
snapshot.data.documents[index].data['memoryName'],
title: snapshot.data.documents[index].data['title'],
description:
snapshot.data.documents[index].data['desc'],
imgUrl: snapshot.data.documents[index].data['imgUrl'],
);
});
},
)
],
)
: Container(
alignment: Alignment.center,
child: CircularProgressIndicator(),
),
);

Flutter dynamic height of ListView

I am developing a Flutter application and I want to dynamically adjust the height of the ListView.
I want the list to have a maximum height of 200. If the height is more than that, user will have to scroll to reach the bottom. If height is below 200, it will take only as much space as needed.
Preview of application: Screenshot. As you can see Restaurants nearby is pushed to the very bottom of the page. I want the ListView to only take height of 200 or less so that the content below isn't pushed to the bottom.
Here is my current code:
#override
Widget build(BuildContext context) {
return Container(
padding: EdgeInsets.all(10.0),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
'Restaurants nearby',
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
),
),
Divider(),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
RaisedButton(
child: Text('Enter restaurant manually'),
onPressed: () {
print('Button pressed');
},
),
],
),
Flexible(
child: ListView.builder(
itemBuilder: (BuildContext context, int index) {
return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.cyan,
),
title: Text('Test restaurant'),
subtitle: Text('80m'),
);
},
itemCount: 15,
),
),
Text(
'Restaurants nearby',
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
),
),
],
),
);
}
You are using Flexible widget, that's why your ListView expands. You have to change Flexible to ConstrainedBox and add shrinkWrap: true to your ListView.
ConstrainedBox(
constraints: BoxConstraints(maxHeight: 200, minHeight: 56.0),
child: ListView.builder(
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.cyan,
),
title: Text('Test restaurant'),
subtitle: Text('80m'),
);
},
itemCount: 15,
),
),
More info here: https://api.flutter.dev/flutter/widgets/ConstrainedBox-class.html
You can use LimitedBox
Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(...),
Divider(),
Row(...),
LimitedBox(
maxHeight: 200.0,
child: ListView.builder(...),
),
Text(...),
],
),
Recommended solution in case when the incoming constraints are unbounded
Consider wrapping the ListView into this
LimitedBox(
maxHeight: 200,
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
Flexible(
child: ListView.builder(
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.cyan,
),
title: Text('Test restaurant'),
subtitle: Text('80m'),
);
},
itemCount: _itemsCount,
),
),
]
)
),
Note that:
shrinkWrap of ListView is set to true
mainAxisSize of Column is set to MainAxisSize.min
maxHeight of LimitedBox is set to 200
A complete snippet:
import 'package:flutter/material.dart';
class DebugWidget extends StatefulWidget {
#override
_DebugWidgetState createState() => _DebugWidgetState();
}
class _DebugWidgetState extends State<DebugWidget> {
int _itemsCount = 1;
#override
Widget build(BuildContext context) {
Widget child = Container(
padding: EdgeInsets.all(10.0),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
'Restaurants nearby',
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
),
),
Divider(),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
RaisedButton(
child: Text('Enter restaurant manually'),
onPressed: () {
print('Button pressed');
},
),
RaisedButton(
child: Text('+1'),
onPressed: () {
setState(() {
_itemsCount += 1;
});
},
),
RaisedButton(
child: Text('-1'),
onPressed: () {
setState(() {
_itemsCount -= 1;
});
},
),
],
),
LimitedBox(
maxHeight: 200,
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
Flexible(
child: ListView.builder(
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.cyan,
),
title: Text('Test restaurant'),
subtitle: Text('80m'),
);
},
itemCount: _itemsCount,
),
),
]
)
),
Text(
'Restaurants nearby',
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold,
),
),
],
),
);
return Scaffold(
body: child,
);
}
}
I found a solution to this problem. you should wrap your ListView with LimittedBox or ConstraintBox and give them maxHeight and set shrinkWrap property of ListView to true. the solution would be something like this.
LimitedBox(
maxHeight: 200,
child: ListView.builder(
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return ListTile(
leading: CircleAvatar(
backgroundColor: Colors.cyan,
),
title: Text('Test restaurant'),
subtitle: Text('80m'),
);
},
itemCount: 15,
),
),
I see that this question has never been answered only with giving a fixed height, so here is what works for me.
For some reason if you set the shrinkwrap to true it doesn't look like it is working but it does, the problem is in the padding settings of the ListView, set the padding to edgeinstets.zero. That fixes it for me.
Wrap inside a Flexible
ShrinkWrap true
Padding, zero
and if needed the column to MainAxisSize.min.
Hope it helps some people.
Example of my code:
Flexible(
child: Container(
decoration: BStyles.cardDecoration1,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
const Text(
'PRODUCTION TASKS',
),
const SizedBox(
height: textVerticalSpacing,
),
Flexible(
child: ListView.builder(
itemCount: recentTasks.length,
padding: EdgeInsets.zero,
physics: const NeverScrollableScrollPhysics(),
shrinkWrap: true,
itemBuilder: (BuildContext context, int index) {
return TaskCard(
task: recentTasks[index],
widthInfo: MediaQuery.of(context).size.width * 0.6,
);
},
),
),
const SizedBox(
height: itemSpacing,
),
Align(
alignment: Alignment.centerRight,
child: InkWell(
onTap: () { },
child: const Text(
'View more',
),
),
),
const SizedBox(
height: textVerticalSpacing,
),
],
),
),
),
),
ConstrainedBox(
constraints: BoxConstraints(maxHeight: 200.0),
child: [your child here],
)
This make your child's height not bigger than 200.0
You can always size the ListView container as % of the viewport (assuming of course that the other widgets also are sized in the same manner):
return Container(
height: MediaQuery.of(context).size.height * 0.75,
child: ListView.builder(
itemBuilder: (ctx, index) {
return Card(...