A List That Scrolls

Part of the Lists and Screens section of Coddy's Flutter journey. Lesson 1 of 33.

A Column is as tall as everything in it. When that is taller than the screen, the bottom is cut off, and Flutter paints yellow and black stripes where it overflows.

A ListView takes the same children: as a Column, but it scrolls. Drag it up on the phone and the rest of the list comes into view.

ListView(
  children: [
    Text('One'),
    Text('Two'),
    Text('Three'),
  ],
)

A ListView fills the space it is given and always starts at the top, so it has no mainAxisSize and no mainAxisAlignment.

Challenge

Easy

The app lists 20 cities in a Column, and most of them do not fit: look for the stripes at the bottom of the phone. Change the Column to a ListView so you can scroll down to Wellington, the last city.

Try it yourself

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    final List<String> cities = [
      'Amsterdam',
      'Bangkok',
      'Cairo',
      'Dublin',
      'Edinburgh',
      'Florence',
      'Geneva',
      'Havana',
      'Istanbul',
      'Jakarta',
      'Kyoto',
      'Lima',
      'Madrid',
      'Nairobi',
      'Oslo',
      'Paris',
      'Quito',
      'Rome',
      'Seoul',
      'Wellington',
    ];
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        appBar: AppBar(title: const Text('Cities')),
        body: Column(
          children: [
            for (String city in cities)
              Padding(
                padding: const EdgeInsets.all(16),
                child: Text(city, style: const TextStyle(fontSize: 24)),
              ),
          ],
        ),
      ),
    );
  }
}