Quiz App

 Quiz App:

main.dart

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:quiz_app/home.dart';
import 'package:quiz_app/quizscreen.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      theme: ThemeData.dark(),
      home: Splashscreen(),
    );
  }
}

class Splashscreen extends StatefulWidget {
  @override
  _SplashscreenState createState() => _SplashscreenState();
}

class _SplashscreenState extends State<Splashscreen> {
  @override
  void initState() {
    super.initState();
    Timer(Duration(seconds: 4), () {
      Navigator.pushReplacement(
          context, MaterialPageRoute(builder: (context) => home()));
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Image.asset(
              "images/il.png",
              height: 120,
              width: 120,
            ),
          ],
        ),
        // child: Text(
        //   "Insta Quiz",
        //   style: TextStyle(
        //     fontSize: 24,
        //   ),
        // ),
      ),
    );
  }
}

home.dart

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:argon_buttons_flutter/argon_buttons_flutter.dart';
import 'package:flutter_spinkit/flutter_spinkit.dart';
import 'package:quiz_app/quizscreen.dart';

class home extends StatefulWidget {
  @override
  _homeState createState() => _homeState();
}

class _homeState extends State<home> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Container(
          width: 500,
          decoration: BoxDecoration(
            image: DecorationImage(
              image: AssetImage(
                "images/qb.jpg",
              ),
              fit: BoxFit.cover,
            ),
          ),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              SizedBox(
                height: 350,
              ),
              // Image.asset(
              //   "images/m.png",
              //   fit: BoxFit.cover,
              // ),
              ArgonTimerButton(
                height: 50,
                width: MediaQuery.of(context).size.width * 0.45,
                onTap: (startTimer, btnState) {
                  if (btnState == ButtonState.Idle) {
                    startTimer(5);
                    Navigator.pushReplacement(context,
                        MaterialPageRoute(builder: (context) => quizscreen()));
                  }
                },
                child: Text(
                  "Play Now",
                  style: TextStyle(
                      color: Colors.black,
                      fontSize: 24,
                      fontWeight: FontWeight.w700),
                ),
                loader: (timeLeft) {
                  return Container(
                    decoration: BoxDecoration(
                        color: Colors.white,
                        borderRadius: BorderRadius.circular(50)),
                    margin: EdgeInsets.all(5),
                    alignment: Alignment.center,
                    width: 40,
                    height: 40,
                    child: Text(
                      "",
                      style:
                          TextStyle(fontSize: 20, fontWeight: FontWeight.w700),
                    ),
                  );
                },
                borderRadius: 15.0,
                color: Colors.white70,
              ),
            ],
          ),
        ),
      ),
    );
  }
}

Quiz screen.dart
import 'package:flutter/material.dart';
import 'package:quiz_app/answer.dart';
import 'package:quiz_app/brain.dart';

class quizscreen extends StatefulWidget {
  @override
  _quizscreenState createState() => _quizscreenState();
}

class _quizscreenState extends State<quizscreen> {
  Brain brain = Brain();
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Center(
            child: Text(
          "Insta Quiz",
          style: TextStyle(
            fontSize: 24,
          ),
        )),
        elevation: 0.0,
        backgroundColor: Colors.transparent,
      ),
      body: Container(
        margin: EdgeInsets.symmetric(
          vertical: 30,
          horizontal: 16,
        ),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Expanded(
              flex: 5,
              child: Center(
                  child: Text(
                brain.getQuestionText,
                textAlign: TextAlign.center,
                style: TextStyle(
                  fontSize: 25,
                ),
              )),
            ),
            Expanded(
              child: AnswerButton(
                text: "true",
                color: Colors.green,
                onPressed: () {
                  setState(() {
                    if (brain.getQuestionAnswer == true) {
                      brain.rightIcon();
                    } else {
                      brain.wrongIcon();
                    }
                    brain.Updatequesion(context);
                  });
                },
              ),
            ),
            Expanded(
              child: AnswerButton(
                text: "false",
                color: Colors.red,
                onPressed: () {
                  setState(() {
                    if (brain.getQuestionAnswer == false) {
                      brain.rightIcon();
                    } else {
                      brain.wrongIcon();
                    }
                    brain.Updatequesion(context);
                  });
                },
              ),
            ),
            SizedBox(
              height: 40,
            ),
            Text(
              "Your Answer",
              style: TextStyle(
                color: Colors.yellow,
                fontSize: 18,
              ),
            ),
            Container(
              margin: EdgeInsets.symmetric(
                vertical: 15,
                horizontal: 16,
              ),
              child: Row(
                children: brain.righticons,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

result.dart
import 'package:flutter/material.dart';
import 'package:quiz_app/answer.dart';
import 'package:quiz_app/brain.dart';
import 'package:quiz_app/home.dart';
import 'package:quiz_app/quizscreen.dart';

class result extends StatelessWidget {
  Brain brain = Brain();
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Center(
            child: Text(
          "Result",
          style: TextStyle(
            fontSize: 34,
          ),
        )),
        elevation: 0.0,
        backgroundColor: Colors.transparent,
      ),
      body: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: <Widget>[
          SizedBox(
            height: 130,
          ),
          Center(
            child: Text(
              "Thanks for Playing",
              style: TextStyle(
                fontWeight: FontWeight.w500,
                fontSize: 24,
              ),
            ),
          ),
          SizedBox(
            height: 50,
          ),
          Icon(
            Icons.thumb_up,
            color: Colors.yellow,
            size: 45,
          ),
          SizedBox(
            height: 130,
          ),
          AnswerButton(
            text: "Restart",
            color: Colors.pink,
            onPressed: () {
              brain.restartquiz();
              Navigator.pushReplacement(
                context,
                MaterialPageRoute(
                  builder: (context) => home(),
                ),
              );
            },
          )
        ],
      ),
    );
  }
}

brain.dart
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:quiz_app/question.dart';
import 'package:quiz_app/result.dart';

class Brain {
  List<Question> _questions = [
    Question(
        "1. The hexadecimal number system contains digits from 1 - 15.", false),
    Question(
        "2. The Language that the computer can understand is called Machine Language.",
        true),
    Question("3. MS Word is a hardware.", false),
    Question("4. CPU controls only input data of computer.", false),
    Question("5. GNU / Linux is a open source operating system.", true),
    Question("6. Twitter is an online social networking and blogging service.",
        false),
  ];

  List<Icon> _icons = [];

  var _questionIndex = 0;

  bool get getQuestionAnswer {
    return _questions[_questionIndex].questionAnswer;
  }

  String get getQuestionText {
    return _questions[_questionIndex].questionText;
  }

  void Updatequesion(context) {
    if (_questionIndex < _questions.length - 1) {
      _questionIndex++;
    } else {
      Navigator.pushReplacement(
        context,
        MaterialPageRoute(
          builder: (context) => result(),
        ),
      );
    }
  }

  void restartquiz() {
    _questionIndex = 0;
  }

  List<Icon> get righticons {
    return _icons;
  }

  void rightIcon() {
    _icons.add(Icon(
      Icons.check,
      color: Colors.green,
    ));
  }

  void wrongIcon() {
    _icons.add(Icon(
      Icons.close,
      color: Colors.red,
    ));
  }
}

question.dart
class Question {
  final String questionText;
  final bool questionAnswer;

  Question(this.questionText, this.questionAnswer);
}

answer.dart
import 'package:flutter/material.dart';

class AnswerButton extends StatelessWidget {
  final String text;
  final Color color;
  final Function onPressed;

  AnswerButton({this.text, this.color, this.onPressed});
  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: onPressed,
      child: Container(
        height: 60,
        width: double.infinity,
        decoration: BoxDecoration(
          color: color,
          borderRadius: BorderRadius.circular(15),
        ),
        margin: EdgeInsets.symmetric(horizontal: 20.0, vertical: 10.0),
        child: Center(
            child: Text(
          text,
          style: TextStyle(
            fontWeight: FontWeight.w500,
            fontSize: 22,
          ),
        )),
      ),
    );
  }
}