Flutter ListView.builder() example

In Flutter, ListView.builder() is used to render long or infinite lists, especially lists of data fetched from APIs like products, news, messages, search results… Only visible items of the lists are called to reduce resource (CPU, RAM) consumption and improve performance.

Example

1. Create a new Flutter project with the following:

flutter create my_product_list

2. Remove all the default code in lib/main.dart and add the following:

import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      // Hide the debug banner
      debugShowCheckedModeBanner: false,
      title: 'Kindacode.com',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.blue),
        useMaterial3: true,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatelessWidget {
  MyHomePage({Key? key}) : super(key: key);

  // Generate a massive list of dummy products
  final myProducts = List<String>.generate(1000, (i) => 'Product $i');

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: const Text('KindaCode.com'),
        ),
        // implement the list view
        body: ListView.builder(
            // the number of items in the list
            itemCount: myProducts.length,

            // display each item of the product list
            itemBuilder: (context, index) {
              return Card(
                // In many cases, the key isn't mandatory
                key: ValueKey(myProducts[index]),
                margin: const EdgeInsets.symmetric(vertical: 5, horizontal: 15),
                child: Padding(
                    padding: const EdgeInsets.all(10),
                    child: Text(myProducts[index])),
              );
            }));
  }
}

3. Run the project:

flutter run

The result:

Conclusion

We’ve examined a complete example of implementing a list view in Flutter with the ListView.builder constructor. If you’d like to learn more new and interesting stuff about mobile development, take a look at the following articles:

• How to create a Filter/Search ListView in Flutter
• Working with ReorderableListView in Flutter
• Flutter & Dart: Count Occurrences of each Element in a List
• Sorting Lists in Dart and Flutter (5 Examples)
• Flutter SliverList – Tutorial and Example
• Flutter AnimatedList – Tutorial and Examples

You can also check out our Flutter topic page or Dart topic page for the latest tutorials and examples.