Snake game by flutter

 Snake game: Created by flutter framework

Home screen

Game screen

Game's video

Code here

main.dart

import 'package:flutter/material.dart';
import 'package:snake/cover_page.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      debugShowCheckedModeBanner: false,
      home: MyCoverPage(),
    );
  }
}

cover_page.dart

import 'package:avatar_glow/avatar_glow.dart';
import 'package:flutter/material.dart';
import 'package:google_fonts/google_fonts.dart';
import 'home_page.dart';

class MyCoverPage extends StatefulWidget {
  const MyCoverPage({Key? key}) : super(key: key);

  @override
  State<MyCoverPage> createState() => _MyCoverPageState();
}

class _MyCoverPageState extends State<MyCoverPage> {
  static var myNewFont = GoogleFonts.pressStart2p(
      textStyle: const TextStyle(
        color: Colors.black,
        letterSpacing: 3,
      ));

  static var myNewFontWhite = GoogleFonts.pressStart2p(
      textStyle:
      const TextStyle(color: Colors.white, letterSpacing: 3, fontSize: 15));

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.grey[800],
      body: Column(
        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
        children: [
          Expanded(
              child: Center(
                  child: Text(
                    'S N A K E',
                    style: myNewFontWhite,
                  ))),
          Expanded(
              flex: 2,
              child: AvatarGlow(
                endRadius: 140,
                duration: const Duration(seconds: 2),
                repeat: true,
                repeatPauseDuration: const Duration(seconds: 1),
                startDelay: const Duration(seconds: 1),
                child: Container(
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    border: Border.all(
                        style: BorderStyle.none
                    ),
                  ),
                  child: CircleAvatar(
                    backgroundColor: Colors.grey[800],
                    radius: 80.0,
                    child: Image.asset(
                      'assets/images/snake.png',
                      fit: BoxFit.scaleDown,
                      color: Colors.white,
                    ),
                  ),
                ),
              )),
          Expanded(
              child: Center(
                  child: Text(
                    '@MS HASAN',
                    style: myNewFontWhite,
                  ))),

          GestureDetector(
            onTap: (){
              Navigator.push(context, MaterialPageRoute(builder: (context) => const HomePage()));
            },
            child: Padding(
              padding: const EdgeInsets.only(left: 30, right: 30, bottom: 60),
              child: ClipRRect(
                borderRadius: BorderRadius.circular(20),
                child: Container(
                  padding: const EdgeInsets.all(8.0),
                  color: Colors.white,
                  child: Text('PLAY GAME', style: myNewFont,),
                ),
              ),
            ),
          )
        ],
      ),
    );
  }
}

home_page.dart

import 'dart:async';
import 'dart:math';

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

import 'cover_page.dart';


class HomePage extends StatefulWidget {
  const HomePage({Key? key}) : super(key: key);

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {


  //snake position
  static List<int> snakePosition = [45, 65, 85, 105, 125];
  final int numberOfSquare = 760;
  bool gameIsRunning = false;


  //google fonts
   static var myNewFontWhite = GoogleFonts.pressStart2p(
     textStyle: const TextStyle(
       letterSpacing: 3, color: Colors.white
     )
   );

  static var myNewFont = GoogleFonts.pressStart2p(
      textStyle: const TextStyle(
          letterSpacing: 3, fontSize: 15
      )
  );

  //Direction
  var direction = 'down';


  //Food topics
  static var randomNumber = Random();
  int foodPosition = randomNumber.nextInt(740);


  //generate random position for food
  void generateNewFood(){
    foodPosition = randomNumber.nextInt(740);
  }

  void startGame(){
    snakePosition = [45, 65, 85, 105, 125];
    if(!gameIsRunning){
      Timer.periodic(const Duration(milliseconds: 400), (timer) {
        upDateSnake();
        gameIsRunning = true;
        if(gameIsOver()){
          timer.cancel();
          gameIsRunning = false;
          showDialogBox();
        }
      });
    }
  }

  bool gameIsOver(){
    for(int i= 0; i < snakePosition.length; i++){
      int counter = 0;
      for(int j = 0; j < snakePosition.length; j++){
        if(snakePosition[i] == snakePosition[j]){
          counter += 1;
        }
        if(counter == 2){
          return true;
        }
      }
    }
    return false;
  }


  showDialogBox(){
    return showDialog(
      barrierDismissible: false,
        context: context,
        builder: (BuildContext context){
          return AlertDialog(
            title: Text('Game over!', style: myNewFont,),
            content: Text('Play Again?', style: myNewFont,),
            actions: [
              ElevatedButton(
                  onPressed: (){
                    setState(() {
                      Navigator.push(context, MaterialPageRoute(builder: (context) => const MyCoverPage()));
                    });
                  },
                  child: Text('No', style: myNewFont,)
              ),
              ElevatedButton(
                  onPressed: (){
                    startGame();
                    Navigator.of(context).pop();
                  },
                  child: Text('Yse', style: myNewFont,)
              ),
            ],
          );
        }
    );
  }

  void upDateSnake(){
    setState(() {
      switch(direction){
        case 'down':
          if(snakePosition.last > 740){
            snakePosition.add(snakePosition.last + 20 - 760);
          }else{
            snakePosition.add(snakePosition.last + 20);
          }
          break;

        case 'up':
          if(snakePosition.last < 20){
            snakePosition.add(snakePosition.last - 20 + 760);
          }else{
            snakePosition.add(snakePosition.last - 20);
          }
          break;
        case 'left':
          if(snakePosition.last % 20 == 0){
            snakePosition.add(snakePosition.last - 1 + 20);
          }else{
            snakePosition.add(snakePosition.last - 1);
          }
          break;

        case 'right':
          if((snakePosition.last + 1) % 20 == 0){
            snakePosition.add(snakePosition.last + 1 - 20);
          }else{
            snakePosition.add(snakePosition.last + 1);
          }
          break;

      default:

      }

      if(snakePosition.last == foodPosition){
        generateNewFood();
      }else{
        snakePosition.removeAt(0);
      }
    });
  }



  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.grey[800],
      body: Column(
        children: [
          Expanded(
            child: GestureDetector(
              onVerticalDragUpdate: (update){
                setState(() {
                  if(direction != 'up' && update.delta.dy > 0){
                    direction = 'down';
                  }else if(direction != 'down' && update.delta.dy < 0){
                    direction = 'up';
                  }
                });
              },
              onHorizontalDragUpdate: (update){
                setState(() {
                  if(direction != 'left' && update.delta.dx > 0){
                    direction = 'right';
                  }else if(direction != 'right' && update.delta.dx < 0){
                    direction = 'left';
                  }
                });
              },
              child: GridView.builder(
                physics: const NeverScrollableScrollPhysics(),
                  itemCount: numberOfSquare,
                  gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                      crossAxisCount: 20),
                  itemBuilder: (BuildContext context, int index) {

                    if (foodPosition == index){
                      return Center(
                        child: Padding(
                          padding: const EdgeInsets.all(2.0),
                          child: ClipRRect(
                            borderRadius: BorderRadius.circular(5),
                            child: Container(
                              color: Colors.yellow,
                            ),
                          ),
                        ),
                      );
                    }
                    if (snakePosition.contains(index)) {
                      return Center(
                        child: Padding(
                          padding: const EdgeInsets.all(2.0),
                          child: ClipRRect(
                            borderRadius: BorderRadius.circular(5),
                            child: Container(
                              color: Colors.white,
                            ),
                          ),
                        ),
                      );
                    }
                    return Center(
                      child: Padding(
                        padding: const EdgeInsets.all(2.0),
                        child: ClipRRect(
                          borderRadius: BorderRadius.circular(5),
                          child: Container(
                            color: Colors.grey[700],
                          ),
                        ),
                      ),
                    );
                  }),
            ),
          ),

          Padding(
            padding: const EdgeInsets.only(top: 8.0),
            child: Text('Score ${snakePosition.length -5}', style: myNewFont,),
          ),

          Padding(
            padding: const EdgeInsets.only(left: 10, right: 10, bottom: 30.0, top: 20),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                GestureDetector(
                  onTap: (){
                    setState(() {
                      if(!gameIsRunning){
                        startGame();
                      }
                    });
                  },
                  child: Text('START' , style: myNewFontWhite,),
                ),
                Text('@MS HASAN', style: myNewFontWhite,),
              ],
            ),
          ),
        ],
      ),
    );
  }
}