Create initial empty application

icons/icon.svg

+<?xml version="1.0" encoding="UTF-8"?>
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+            <feGaussianBlur stdDeviation="0.658125"/>
+        </filter>
+    </defs>
+    <g transform="translate(0 -1093.8)">
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+        </g>
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+            <path d="m0 0h51.2v51.2h-51.2z" fill="none" stroke-width="1.0667"/>
+        </g>
+        <g transform="matrix(.41585 0 0 .41585 84.325 1055.9)">
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+                <g transform="matrix(38.618 0 0 38.618 14724 -13542)">
+                    <g transform="matrix(.71436 0 0 .71436 -400.52 188.34)">
+                        <path d="m1293.2-120.67c-181.75 0.2763-511.18 0.13525-699.05 0.13998-2.3216 10.413-3.593 21.251-3.593 32.384v114c207.65 0.73695 494.72 0.38136 706.23 0.3733v-114.37c0-11.18-1.2522-22.07-3.593-32.523zm-458.69 295.56c-78.385-4e-3 -158.85 0.17892-243.95 0.55995v138.63c286.34-0.39317 421.73-0.13827 706.23-0.32664v-137.75c-163.2-0.53005-311.22-1.1113-462.28-1.1199z" opacity="0" stroke-width="1.4932"/>
+                    </g>
+                </g>
+            </g>
+        </g>
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+    </g>
+    <path d="m12.174 17.928 3.2316-5.0362" fill="none" marker-end="url(#Arrow5)" stroke="#fff" stroke-width=".6599"/>
+</svg>

icons/level_easy.svg

+<?xml version="1.0" encoding="UTF-8"?>
+<svg enable-background="new 0 0 100 100" version="1.1" viewBox="0 0 102 102" xml:space="preserve" xmlns="http://www.w3.org/2000/svg"><rect x="1" y="1" width="100" height="100" ry="0" fill="#6ade98" stroke="#000" stroke-width="2"/></svg>

icons/level_normal.svg

+<?xml version="1.0" encoding="UTF-8"?>
+<svg enable-background="new 0 0 100 100" version="1.1" viewBox="0 0 102 102" xml:space="preserve" xmlns="http://www.w3.org/2000/svg"><rect x="1" y="1" width="100" height="100" ry="0" fill="#6a78de" stroke="#000" stroke-width="2"/></svg>

icons/skin_default.svg

+<?xml version="1.0" encoding="UTF-8"?>
+<svg enable-background="new 0 0 100 100" version="1.1" viewBox="0 0 102 102" xml:space="preserve" xmlns="http://www.w3.org/2000/svg"><rect x="1" y="1" width="100" height="100" ry="0" fill="#be6ade" stroke="#000" stroke-width="2"/></svg>

icons/skins/default/empty.svg

+<?xml version="1.0" encoding="UTF-8"?>
+<svg enable-background="new 0 0 100 100" version="1.1" viewBox="0 0 100 100" xml:space="preserve" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" ry="2" fill="none"/><rect width="100" height="100" fill="#c5c5c5" stroke="#505050" stroke-linecap="round" stroke-linejoin="round" stroke-width="2.6"/></svg>

icons/skins/images/empty.svg

+<?xml version="1.0" encoding="UTF-8"?>
+<svg enable-background="new 0 0 100 100" version="1.1" viewBox="0 0 100 100" xml:space="preserve" xmlns="http://www.w3.org/2000/svg"><rect width="100" height="100" ry="2" fill="none"/><rect width="100" height="100" fill="#c5c5c5" stroke="#505050" stroke-linecap="round" stroke-linejoin="round" stroke-width="2.6"/><path transform="translate(17.493 20.91)" d="m52.013 48.572c-1.2644 1.2655-14.711-7.2436-16.478-6.963s-11.915 12.538-13.509 11.726c-1.5943-0.81141 2.3431-16.23 1.5302-17.823s-15.606-7.4574-15.327-9.2244 16.159-2.7868 17.424-4.0523c1.2644-1.2655 2.2698-17.147 4.0366-17.427 1.7667-0.28064 7.644 14.507 9.2382 15.319 1.5943 0.81141 17.009-3.1399 17.822-1.5464 0.81286 1.5935-11.435 11.753-11.714 13.52s8.2423 15.206 6.9779 16.472z" fill="#6a78de" stroke="#505050" stroke-linecap="round" stroke-linejoin="round" stroke-width="2.6"/></svg>

ios/Flutter/Generated.xcconfig

+// This is a generated file; do not edit or check into version control.
+FLUTTER_ROOT=/home/benoit/snap/flutter/common/flutter
+FLUTTER_APPLICATION_PATH=/home/benoit/dev/perso/android/org.benoitharrault.twister
+COCOAPODS_PARALLEL_CODE_SIGN=true
+FLUTTER_TARGET=lib/main.dart
+FLUTTER_BUILD_DIR=build
+FLUTTER_BUILD_NAME=1.0.0
+FLUTTER_BUILD_NUMBER=1
+EXCLUDED_ARCHS[sdk=iphonesimulator*]=i386
+DART_OBFUSCATION=false
+TRACK_WIDGET_CREATION=false
+TREE_SHAKE_ICONS=false
+PACKAGE_CONFIG=.dart_tool/package_config.json

ios/Flutter/flutter_export_environment.sh

+#!/bin/sh
+# This is a generated file; do not edit or check into version control.
+export "FLUTTER_ROOT=/home/benoit/snap/flutter/common/flutter"
+export "FLUTTER_APPLICATION_PATH=/home/benoit/dev/perso/android/org.benoitharrault.twister"
+export "COCOAPODS_PARALLEL_CODE_SIGN=true"
+export "FLUTTER_TARGET=lib/main.dart"
+export "FLUTTER_BUILD_DIR=build"
+export "FLUTTER_BUILD_NAME=1.0.0"
+export "FLUTTER_BUILD_NUMBER=1"
+export "DART_OBFUSCATION=false"
+export "TRACK_WIDGET_CREATION=false"
+export "TREE_SHAKE_ICONS=false"
+export "PACKAGE_CONFIG=.dart_tool/package_config.json"

ios/Runner/GeneratedPluginRegistrant.h

+//
+//  Generated file. Do not edit.
+//
+
+// clang-format off
+
+#ifndef GeneratedPluginRegistrant_h
+#define GeneratedPluginRegistrant_h
+
+#import <Flutter/Flutter.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface GeneratedPluginRegistrant : NSObject
++ (void)registerWithRegistry:(NSObject<FlutterPluginRegistry>*)registry;
+@end
+
+NS_ASSUME_NONNULL_END
+#endif /* GeneratedPluginRegistrant_h */

ios/Runner/GeneratedPluginRegistrant.m

+//
+//  Generated file. Do not edit.
+//
+
+// clang-format off
+
+#import "GeneratedPluginRegistrant.h"
+
+#if __has_include(<shared_preferences_ios/FLTSharedPreferencesPlugin.h>)
+#import <shared_preferences_ios/FLTSharedPreferencesPlugin.h>
+#else
+@import shared_preferences_ios;
+#endif
+
+@implementation GeneratedPluginRegistrant
+
++ (void)registerWithRegistry:(NSObject<FlutterPluginRegistry>*)registry {
+  [FLTSharedPreferencesPlugin registerWithRegistrar:[registry registrarForPlugin:@"FLTSharedPreferencesPlugin"]];
+}
+
+@end

lib/layout/game.dart

+import 'dart:math';
+
+import 'package:flutter/material.dart';
+
+import '../provider/data.dart';
+import '../utils/game_utils.dart';
+
+class Game {
+
+  static Container buildGameWidget(Data myProvider) {
+    bool gameIsFinished = myProvider.isGameFinished();
+
+    return Container(
+      child: Column(
+        mainAxisAlignment: MainAxisAlignment.start,
+        crossAxisAlignment: CrossAxisAlignment.center,
+        children: [
+          Expanded(
+            child: Text('❇️'),
+          ),
+          SizedBox(height: 2),
+          Container(
+            height: 150,
+            width: double.maxFinite,
+            child: gameIsFinished
+              ? Game.buildEndGameMessage(myProvider)
+              : Text('❇️'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  static FlatButton buildRestartGameButton(Data myProvider) {
+    return FlatButton(
+      child: Container(
+        child: Image(
+          image: AssetImage('assets/icons/button_back.png'),
+          fit: BoxFit.fill,
+        ),
+      ),
+      onPressed: () => GameUtils.resetGame(myProvider),
+    );
+  }
+
+  static Container buildEndGameMessage(Data myProvider) {
+    String decorationImageAssetName = '';
+    if (myProvider.gameWon) {
+      decorationImageAssetName = 'assets/icons/game_win.png';
+    } else {
+      decorationImageAssetName = 'assets/icons/game_fail.png';
+    }
+
+    Image decorationImage = Image(
+      image: AssetImage(decorationImageAssetName),
+      fit: BoxFit.fill
+    );
+
+    return Container(
+      margin: EdgeInsets.all(2),
+      padding: EdgeInsets.all(2),
+
+      child: Table(
+        defaultColumnWidth: IntrinsicColumnWidth(),
+        children: [
+          TableRow(
+            children: [
+              Column(children: [ decorationImage ]),
+              Column(children: [ buildRestartGameButton(myProvider) ]),
+              Column(children: [ decorationImage ]),
+            ],
+          ),
+        ]
+      )
+    );
+  }
+
+}

lib/layout/parameters.dart

+import 'package:flutter/material.dart';
+
+import '../provider/data.dart';
+import '../utils/game_utils.dart';
+
+class Parameters {
+
+  static Container buildParametersSelector(Data myProvider) {
+    return Container(
+      padding: EdgeInsets.all(2),
+      margin: EdgeInsets.all(2),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        mainAxisAlignment: MainAxisAlignment.center,
+        children: [
+          Parameters.buildParameterSelector(myProvider, 'level'),
+          SizedBox(height: 5),
+          Parameters.buildParameterSelector(myProvider, 'skin'),
+          SizedBox(height: 5),
+
+          Parameters.buildStartGameButton(myProvider),
+        ],
+      ),
+    );
+  }
+
+  static Container buildStartGameButton(Data myProvider) {
+    Column decorationImage = Column(
+      children: [
+        Image(
+          image: AssetImage('assets/icons/game_win.png'),
+          fit: BoxFit.fill
+        ),
+      ]
+    );
+
+    return Container(
+      margin: EdgeInsets.all(2),
+      padding: EdgeInsets.all(2),
+
+      child: Table(
+        defaultColumnWidth: IntrinsicColumnWidth(),
+        children: [
+          TableRow(
+            children: [
+              decorationImage,
+              Column(
+                children: [
+                  FlatButton(
+                    child: Container(
+                      child: Image(
+                        image: AssetImage('assets/icons/button_start.png'),
+                        fit: BoxFit.fill,
+                      ),
+                    ),
+                    onPressed: () => GameUtils.startGame(myProvider),
+                  ),
+                ]
+              ),
+              decorationImage,
+            ],
+          ),
+        ]
+      )
+    );
+  }
+
+  static Widget buildParameterSelector(Data myProvider, String parameterCode) {
+    List availableValues = myProvider.getParameterAvailableValues(parameterCode);
+
+    if (availableValues.length == 1) {
+      return SizedBox(height: 1);
+    }
+
+    return Table(
+      defaultColumnWidth: IntrinsicColumnWidth(),
+      children: [
+        TableRow(
+          children: [
+            for (var index = 0; index < availableValues.length; index++)
+              Column(
+                children: [
+                  _buildParameterButton(myProvider, parameterCode, availableValues[index])
+                ]
+              ),
+          ],
+        ),
+      ],
+    );
+  }
+
+  static TextButton _buildParameterButton(Data myProvider, String parameterCode, String parameterValue) {
+    String currentValue = myProvider.getParameterValue(parameterCode).toString();
+
+    bool isActive = (parameterValue == currentValue);
+    String imageAsset = 'assets/icons/' + parameterCode + '_' + parameterValue + '.png';
+
+    return TextButton(
+      child: Container(
+        padding: EdgeInsets.all(2),
+        decoration: BoxDecoration(
+          color: Colors.white,
+          borderRadius: BorderRadius.circular(10),
+          border: Border.all(
+            color: isActive ? Colors.blue : Colors.white,
+            width: 10,
+          ),
+        ),
+        child: Image(
+          image: AssetImage(imageAsset),
+          fit: BoxFit.fill,
+        ),
+      ),
+      onPressed: () => myProvider.setParameterValue(parameterCode, parameterValue),
+    );
+  }
+
+}

lib/main.dart

+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:provider/provider.dart';
+import 'package:overlay_support/overlay_support.dart';
+
+import 'provider/data.dart';
+import 'screens/home.dart';
+
+void main() {
+  WidgetsFlutterBinding.ensureInitialized();
+  SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp])
+      .then((value) => runApp(MyApp()));
+}
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return ChangeNotifierProvider(
+      create: (BuildContext context) => Data(),
+      child: Consumer<Data>(builder: (context, data, child) {
+        return OverlaySupport(
+          child: MaterialApp(
+            debugShowCheckedModeBanner: false,
+            theme: ThemeData(
+              primaryColor: Colors.blue,
+              visualDensity: VisualDensity.adaptivePlatformDensity,
+            ),
+            home: Home(),
+            routes: {
+              Home.id: (context) => Home(),
+            },
+          ));
+      }),
+    );
+  }
+}

lib/provider/data.dart

+import 'package:flutter/foundation.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+class Data extends ChangeNotifier {
+
+  // Configuration available values
+  List _availableLevelValues = ['easy', 'normal'];
+  List _availableSkinValues = ['default'];
+
+  List get availableLevelValues => _availableLevelValues;
+  List get availableSkinValues => _availableSkinValues;
+
+  // Application default configuration
+  String _level = '';
+  String _levelDefault = 'normal';
+  String _skin = '';
+  String _skinDefault = 'default';
+
+  // Game data
+  bool _gameIsRunning = false;
+  bool _gameWon = false;
+
+  String get level => _level;
+  void updateLevel(String level) {
+    _level = level;
+    notifyListeners();
+  }
+
+  String get skin => _skin;
+  void updateSkin(String skin) {
+    _skin = skin;
+    notifyListeners();
+  }
+
+  getParameterValue(String parameterCode) {
+    switch(parameterCode) {
+      case 'level': { return _level; }
+      break;
+      case 'skin': { return _skin; }
+      break;
+    }
+  }
+
+  List getParameterAvailableValues(String parameterCode) {
+    switch(parameterCode) {
+      case 'level': { return _availableLevelValues; }
+      break;
+      case 'skin': { return _availableSkinValues; }
+      break;
+    }
+    return [];
+  }
+
+  setParameterValue(String parameterCode, String parameterValue) async {
+    switch(parameterCode) {
+      case 'level': { updateLevel(parameterValue); }
+      break;
+      case 'skin': { updateSkin(parameterValue); }
+      break;
+    }
+    final prefs = await SharedPreferences.getInstance();
+    prefs.setString(parameterCode, parameterValue);
+  }
+
+  void initParametersValues() async {
+    final prefs = await SharedPreferences.getInstance();
+    setParameterValue('level', prefs.getString('level') ?? _levelDefault);
+    setParameterValue('skin', prefs.getString('skin') ?? _skinDefault);
+  }
+
+  bool get gameIsRunning => _gameIsRunning;
+  void updateGameIsRunning(bool gameIsRunning) {
+    _gameIsRunning = gameIsRunning;
+    notifyListeners();
+  }
+
+  bool isGameFinished() {
+    return false;
+  }
+
+  bool get gameWon => _gameWon;
+
+  void resetGame() {
+    _gameIsRunning = false;
+    _gameWon = false;
+    notifyListeners();
+  }
+
+}

lib/screens/home.dart

+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import 'package:overlay_support/overlay_support.dart';
+
+import '../layout/game.dart';
+import '../layout/parameters.dart';
+import '../provider/data.dart';
+import '../utils/game_utils.dart';
+
+class Home extends StatefulWidget {
+  static const String id = 'home';
+
+  @override
+  _HomeState createState() => _HomeState();
+}
+
+class _HomeState extends State<Home> {
+  @override
+  void initState() {
+    super.initState();
+
+    Data myProvider = Provider.of<Data>(context, listen: false);
+    myProvider.initParametersValues();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    Data myProvider = Provider.of<Data>(context);
+
+    List<Widget> menuActions = [];
+
+    if (myProvider.gameIsRunning) {
+      menuActions = [
+        FlatButton(
+          child: Container(
+            decoration: BoxDecoration(
+              borderRadius: BorderRadius.circular(4),
+              border: Border.all(
+                color: Colors.blue,
+                width: 4,
+              ),
+            ),
+            margin: EdgeInsets.all(8),
+            child: Image(
+              image: AssetImage('assets/icons/button_back.png'),
+              fit: BoxFit.fill
+            ),
+          ),
+          onPressed: () => toast('Long press to quit game...'),
+          onLongPress: () => GameUtils.resetGame(myProvider),
+        ),
+      ];
+    }
+
+    return Scaffold(
+      appBar: AppBar(
+        actions: menuActions,
+      ),
+      body: SafeArea(
+        child: Center(
+          child: myProvider.gameIsRunning
+            ? Game.buildGameWidget(myProvider)
+            : Parameters.buildParametersSelector(myProvider)
+        ),
+      )
+    );
+  }
+}

lib/utils/game_utils.dart

+import '../provider/data.dart';
+
+class GameUtils {
+
+  static Future<void> resetGame(Data myProvider) async {
+    myProvider.updateGameIsRunning(false);
+  }
+
+  static Future<void> startGame(Data myProvider) async {
+    print('Starting game');
+    print('- level: ' + myProvider.level);
+
+    myProvider.resetGame();
+
+    myProvider.updateGameIsRunning(true);
+  }
+
+}

pubspec.lock

+# Generated by pub
+# See https://dart.dev/tools/pub/glossary#lockfile
+packages:
+  async:
+    dependency: transitive
+    description:
+      name: async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.8.2"
+  boolean_selector:
+    dependency: transitive
+    description:
+      name: boolean_selector
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  characters:
+    dependency: transitive
+    description:
+      name: characters
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  charcode:
+    dependency: transitive
+    description:
+      name: charcode
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.1"
+  clock:
+    dependency: transitive
+    description:
+      name: clock
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0"
+  collection:
+    dependency: transitive
+    description:
+      name: collection
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.16.0"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.0"
+  ffi:
+    dependency: transitive
+    description:
+      name: ffi
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.2"
+  file:
+    dependency: transitive
+    description:
+      name: file
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "6.1.2"
+  flutter:
+    dependency: "direct main"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_web_plugins:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  js:
+    dependency: transitive
+    description:
+      name: js
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.6.4"
+  matcher:
+    dependency: transitive
+    description:
+      name: matcher
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.12.11"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.1.4"
+  meta:
+    dependency: transitive
+    description:
+      name: meta
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.7.0"
+  nested:
+    dependency: transitive
+    description:
+      name: nested
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.0"
+  overlay_support:
+    dependency: "direct main"
+    description:
+      name: overlay_support
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.1"
+  path:
+    dependency: transitive
+    description:
+      name: path
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.8.1"
+  path_provider_linux:
+    dependency: transitive
+    description:
+      name: path_provider_linux
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.5"
+  path_provider_platform_interface:
+    dependency: transitive
+    description:
+      name: path_provider_platform_interface
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.3"
+  path_provider_windows:
+    dependency: transitive
+    description:
+      name: path_provider_windows
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.5"
+  platform:
+    dependency: transitive
+    description:
+      name: platform
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "3.1.0"
+  plugin_platform_interface:
+    dependency: transitive
+    description:
+      name: plugin_platform_interface
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.2"
+  process:
+    dependency: transitive
+    description:
+      name: process
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "4.2.4"
+  provider:
+    dependency: "direct main"
+    description:
+      name: provider
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "6.0.2"
+  shared_preferences:
+    dependency: "direct main"
+    description:
+      name: shared_preferences
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.13"
+  shared_preferences_android:
+    dependency: transitive
+    description:
+      name: shared_preferences_android
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.11"
+  shared_preferences_ios:
+    dependency: transitive
+    description:
+      name: shared_preferences_ios
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  shared_preferences_linux:
+    dependency: transitive
+    description:
+      name: shared_preferences_linux
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  shared_preferences_macos:
+    dependency: transitive
+    description:
+      name: shared_preferences_macos
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.3"
+  shared_preferences_platform_interface:
+    dependency: transitive
+    description:
+      name: shared_preferences_platform_interface
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.0"
+  shared_preferences_web:
+    dependency: transitive
+    description:
+      name: shared_preferences_web
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.0.3"
+  shared_preferences_windows:
+    dependency: transitive
+    description:
+      name: shared_preferences_windows
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  sky_engine:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.99"
+  source_span:
+    dependency: transitive
+    description:
+      name: source_span
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.8.2"
+  stack_trace:
+    dependency: transitive
+    description:
+      name: stack_trace
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.10.0"
+  stream_channel:
+    dependency: transitive
+    description:
+      name: stream_channel
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  string_scanner:
+    dependency: transitive
+    description:
+      name: string_scanner
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0"
+  term_glyph:
+    dependency: transitive
+    description:
+      name: term_glyph
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  test_api:
+    dependency: transitive
+    description:
+      name: test_api
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.4.9"
+  vector_math:
+    dependency: transitive
+    description:
+      name: vector_math
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.2"
+  win32:
+    dependency: transitive
+    description:
+      name: win32
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.4.1"
+  xdg_directories:
+    dependency: transitive
+    description:
+      name: xdg_directories
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.2.0+1"
+sdks:
+  dart: ">=2.17.0-0 <3.0.0"
+  flutter: ">=2.8.0"

pubspec.yaml

+name: calculus
+description: calculus application
+publish_to: 'none'
+version: 1.0.0+1
+
+environment:
+  sdk: ">=2.16.1 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  provider: ^6.0.2
+  shared_preferences: ^2.0.6
+  overlay_support: ^1.0.0
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+
+flutter:
+  uses-material-design: true
+  assets:
+    - assets/icons/

test/widget_test.dart

+// This is a basic Flutter widget test.
+//
+// To perform an interaction with a widget in your test, use the WidgetTester
+// utility that Flutter provides. For example, you can send tap and scroll
+// gestures. You can also use WidgetTester to find child widgets in the widget
+// tree, read text, and verify that the values of widget properties are correct.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:twister/main.dart';
+
+void main() {
+  testWidgets('Counter increments smoke test', (WidgetTester tester) async {
+    // Build our app and trigger a frame.
+    await tester.pumpWidget(const MyApp());
+
+    // Verify that our counter starts at 0.
+    expect(find.text('0'), findsOneWidget);
+    expect(find.text('1'), findsNothing);
+
+    // Tap the '+' icon and trigger a frame.
+    await tester.tap(find.byIcon(Icons.add));
+    await tester.pump();
+
+    // Verify that our counter has incremented.
+    expect(find.text('0'), findsNothing);
+    expect(find.text('1'), findsOneWidget);
+  });
+}