Datasets:
Ekhlass
/
Flutter_Documentation

Dataset card Data Studio Files Community
1
text
stringlengths
1
474
setState(() {
widgets = List.from(widgets);
widgets.add(getRow(widgets.length));
developer.log('row $i');
});
},
child: Padding(
padding: const EdgeInsets.all(10),
child: Text('Row $i'),
),
);
}
}<code_end>
The recommended, efficient, and effective way to build a list uses a
ListView.Builder. This method is great when you have a dynamic
List or a List with very large amounts of data. This is essentially
the equivalent of RecyclerView on Android, which automatically
recycles list elements for you:
<code_start>import 'dart:developer' as developer;
import 'package:flutter/material.dart';
void main() {
runApp(const SampleApp());
}
class SampleApp extends StatelessWidget {
const SampleApp({super.key});
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Sample App',
theme: ThemeData(
colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
),
home: const SampleAppPage(),
);
}
}
class SampleAppPage extends StatefulWidget {
const SampleAppPage({super.key});
@override
State<SampleAppPage> createState() => _SampleAppPageState();
}
class _SampleAppPageState extends State<SampleAppPage> {
List<Widget> widgets = [];
@override
void initState() {
super.initState();
for (int i = 0; i < 100; i++) {
widgets.add(getRow(i));
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Sample App'),
),
body: ListView.builder(
itemCount: widgets.length,
itemBuilder: (context, position) {
return getRow(position);
},
),
);
}
Widget getRow(int i) {
return GestureDetector(
onTap: () {
setState(() {
widgets.add(getRow(widgets.length));
developer.log('row $i');
});
},
child: Padding(
padding: const EdgeInsets.all(10),
child: Text('Row $i'),
),
);
}
}<code_end>
Instead of creating a “ListView”, create a
ListView.builder that takes two key parameters: the
initial length of the list, and an ItemBuilder function.The ItemBuilder function is similar to the getView
function in an Android adapter; it takes a position,
and returns the row you want rendered at that position.Finally, but most importantly, notice that the onTap() function
doesn’t recreate the list anymore, but instead .adds to it.<topic_end>
<topic_start>
Working with text
<topic_end>
<topic_start>
How do I set custom fonts on my Text widgets?
In Android SDK (as of Android O), you create a Font resource file and
pass it into the FontFamily param for your TextView.In Flutter, place the font file in a folder and reference it in the
pubspec.yaml file, similar to how you import images.Then assign the font to your Text widget:
<code_start>@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Sample App'),
),