Quiz: The Question

Part of the Projects section of Coddy's Flutter journey. Lesson 10 of 36.

The second app is a quiz about Flutter itself: a question, four answers to tap, green for right and red for wrong, a score and a results screen.

The questions are already in the starter. Each one is a Question with its text, its four answers and the position of the right one:

Question('Which language do you write Flutter apps in?',
    ['Kotlin', 'Swift', 'Dart', 'JavaScript'], 2),

Positions start at 0, so 2 is 'Dart'. The state keeps _index, the question you are on, and questions[_index] is that question.

The answers are a collection for inside the Column: one button per answer. FilledButton.tonal is a soft filled button in the theme's color, good for a set of choices. With crossAxisAlignment: CrossAxisAlignment.stretch the column makes every child as wide as it is, so all four buttons line up edge to edge.

Challenge

Easy

Show the first question:

add int _index = 0; to the state
replace the Center with a Column in 24 pixels of padding that stretches its children across
in it: the question's text in the theme's headlineSmall style, 24 pixels of space, then a FilledButton.tonal for each answer, with 16 pixels of padding inside and 12 pixels under each one

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) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
      ),
      home: const QuizScreen(),
    );
  }
}

class Question {
  const Question(this.text, this.answers, this.correct);

  final String text;
  final List<String> answers;
  final int correct;
}

const List<Question> questions = [
  Question('Which widget stacks its children from top to bottom?', ['Row', 'Column', 'Stack', 'Wrap'], 1),
  Question('Which language do you write Flutter apps in?', ['Kotlin', 'Swift', 'Dart', 'JavaScript'], 2),
  Question('What does setState do?', ['Rebuilds the widget', 'Saves the app', 'Closes the screen', 'Plays a sound'], 0),
  Question('Which widget shows a list you can scroll?', ['Container', 'SizedBox', 'Padding', 'ListView'], 3),
  Question('Which widget adds space around its child?', ['Padding', 'Center', 'Icon', 'Text'], 0),
];

class QuizScreen extends StatefulWidget {
  const QuizScreen({super.key});

  @override
  State<QuizScreen> createState() => _QuizScreenState();
}

class _QuizScreenState extends State<QuizScreen> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Flutter Quiz')),
      body: const Center(
        child: Text('Your quiz goes here'),
      ),
    );
  }
}