Flutter Flutter Google I/O 23 Recap 1

박제창 @Dreamwalker Dreamus Company Flutter Seoul GDG Golang Korea Intro @Dreamwalker

Dreamus Company 3

GDG Golang Korea https://festa.io/events/3435 4

Flutter Seoul 5 Flutter Seoul Flutter Songdo Flutter Daegu

Flutter Seoul https://festa.io/events/3775 6

“Do You Know… Flutter?” ~2020 JaiChang Park 7

“Are you using Flutter?” 2020~ JaiChang Park 8

Flutter is an open source framework by Google for building beautiful, natively compiled, multi-platform applications from a single codebase. https://flutter.dev/ What’s Flutter Intro 9

Flutter Architecture Layers Intro 10

2023-04-01 Flutter Forward Extended Korea Intro 11 ● https://speakerdeck.com/itsmedreamwalker/flutter-forward-extended-korea-flutter-2023-roadmap ● https://youtu.be/x7wB89Wmu_A

1. Custom asset transformers, because they enable some performance improvements. 2. Efficient 2D scrolling widgets (e.g. tables and trees), to improve the performance of applications with this kind of interface. 3. Multiple windows, especially for desktop platforms, because this is a very highly requested feature. 4. Platform Views on macOS and Windows, by popular demand. 5. Drag and drop, also by popular demand. 6. Wireless debugging on iOS, our second-most-requested feature. 7. Custom "flutter create" templates, which makes it much easier for third-parties (e.g. the Flame engine) to bootstrap developers. 8. Supporting element embedding (see also #32329), which allows Flutter content to be added to any standard web

Intro 13

Intro 14

I/O FLIP 15 An AI-designed card game powered by Google, built for Google I/O 2023 ● https://flip.withgoogle.com/#/ ● https://github.com/flutter/io_flip

“Included everywhere! Android, Chrome, AI!” @timsneath 16

Learn the latest from Dart and Flutter, including how they enable you to build beautiful native apps for any platform. This session covers breakthrough graphics performance, seamless integration, emerging architectures and platforms, and developer experience. What's new in Dart and Flutter Section 01 17

Flutter 3.10 ! Section 01 18 What's new in Dart and Flutter .6

Material 3 지원 확대 연관 세션 1. What’s New in Material Design 2. Design for every device with Flutter and Material 3 100% Sound null safety New : Patterns New: Class modifiers Material 3 Dart 3 UI Upgraded to use Material 3 Trace Viewer based on Perfetto DevTools 01 02 03 Section 01 19 What's new in Dart and Flutter 📌 Section Pick 📌 Section Pick

OrbShader Custom Shader GLSL 연관 세션 Building next-gen UIs in Flutter Breakthrough graphics performance. New Rendering Engine Production ready for iOS 연관 세션 Tour of Impeller - Flutter's new rendering engine Fragment Shaders for Web Impeller Flutter Web Wasm (WebAssembly) 연관 세션 Evolving Flutter's support for the web Wasm 04 05 06 Section 01 20 What's new in Dart and Flutter

Dart 3 Section 01 21 What's new in Dart and Flutter ● 100% Sound Null Safety ○ Reduce run-time errors from nulls ○ Smaller compiled output ○ Improved performance ● New Patterns → Modern programming ○ Structured data with records ○ Pattern matching ● New Class Modifiers

Dart 3 Section 01 22 What's new in Dart and Flutter ● 100% Sound Null Safety ○ Null Safety는 Dart 2.12 버전때 소개되어 약 2년정도 시간 경과 ○ dart migrate tool 제거 → SDK 2.19 사용하여 migrate 수행 필요

Dart 3 Section 01 23 What's new in Dart and Flutter ● New: Records & Patterns ○ Records는 Dart SDK 3.0 버전에 새로 적용된 Type ○ Pattern은 Dart 언어의 a syntactic category ■ statements and expressions ■ match a value, destructure a value New Feature

Dart 3 Section 01 24 What's new in Dart and Flutter ● What are Records ○ First-class : Store in variables, return from functions ■ 변수를 저장하고, 함수로부터 값을 반환, 제네릭 타입 사용 ○ Objects: Subtype of Record which extends Object ○ Value semantics: Automatic == and hashCode ○ Optimizable: No persistent identity → Compiler can optimize away

var io23SeoulSpeaker = { 'name': "Dreamwalker", "part": "Flutter", "track": 2, }; List speakerInfo(Map json) { return [ json['name'] as String, json["part"] as String, json['track'] as int, ]; } 25

var info = speakerInfo(io23SeoulSpeaker); var name = info[0] as String; var part = info[1] as String; var track = info[2] as int; 26

class IO23Seoul { final String name; final String part; final int track; IO23Seoul(this.name, this.part, this.track); } 27

var io23SeoulSpeaker = {'name': "Dreamwalker", "part": "Flutter", "track": 2}; IO23Seoul speakerInfo(Map json) { return IO23Seoul( json['name'] as String, json["part"] as String, json['track'] as int, ); } var info = speakerInfo(io23SeoulSpeaker); var name = info.name; var part = info.part; var track = info.track; 28

(String, String, int) speakerInfo(Map json) { return ( json['name'] as String, json["part"] as String, json['track'] as int, ); } var info = speakerInfo(io23SeoulSpeaker); var name = info.$1; var part = info.$2; var track = info.$3; 29

// method 1 var record = ('first', a: 2, b: true, 'last'); // method 2 (int x, int y, int z) point = (1, 2, 3); // method 3 ({int x, int y, int z}) point = (x: 1, y: 2, z: 3); 30

// pattern // Before var info = speakerInfo(io23SeoulSpeaker); // Pattern var (name, part, track) = speakerInfo(io23SeoulSpeaker); // Pattern var (name, _, track) = speakerInfo(io23SeoulSpeaker); 31

// Pattern - Destructuring // Before var json = { 'user': ['Dreamwalker', "Flutter", 2] }; var name = json['user']?[0]; var track = json['track']?[1]; 32

// Pattern - Destructuring // After var json = { 'speaker': ['Dreamwalker', 2] }; var {"speaker": [name, track]} = json; 33

// Pattern - Switch body: Center( child: isVisible ? Column( mainAxisAlignment: MainAxisAlignment.center, children: [ Text( '$_counter', style: Theme.of(context).textTheme.headlineMedium, ), _counter > 10 ? Text("10 초과") : Container(), ], ) : ListView.builder( itemBuilder: (context, index) => ListTile(), ), ), 34

// Pattern - Switch body: Center( child: switch (isVisible) { true => Column( mainAxisAlignment: MainAxisAlignment.center, children: [ Text( '$_counter', style: Theme.of(context).textTheme.headlineMedium, ), switch (_counter) { var a when a > 10 => Text("10 초과"), _ => Container(), }, ], ), false => ListView.builder(itemBuilder: (_, __) => ListTile()) }), 35

Dart 3 Section 01 36 What's new in Dart and Flutter ● New: Class Modifiers ○ abstract ○ base ○ final ○ interface ○ sealed ○ mixin

sealed class Burger {} class CheeseBurger extends Burger { final int count; CheeseBurger(this.count); } class DoubleCheeseBurger extends Burger { final int count; DoubleCheeseBurger(this.count); } int calculateCheese(Burger burger) => switch (burger) { CheeseBurger(count: int c) => 1 * c, DoubleCheeseBurger(count: int c) => 1 * c, }; 37

sealed class AuthException implements Exception {} class EmailException extends AuthException { EmailException(this.email); final String email; } class WeakPasswordException extends AuthException {} class WrongPasswordException extends AuthException {} class UserNotFoundException extends AuthException {} 38

String describe(AuthException exception) { return switch (exception) { EmailException(email: final email) => 'Email already in use: $email', WeakPasswordException() => 'Password is too weak', WrongPasswordException() => 'Wrong password', UserNotFoundException() => 'User not found', }; } print(“${describe(e)}”); 39

Dart 3 Section 01 40 What's new in Dart and Flutter 다양한 조합.. ○ abstract ○ base ○ final ○ interface ○ sealed ○ mixin Declaration Construct? Extend? Implement? Mix in? Exhaustive? class Yes Yes Yes No No base class Yes Yes No No No interface class Yes No Yes No No final class Yes No No No No sealed class No No No No Yes abstract class No Yes Yes No No abstract base class No Yes No No No abstract interface class No No Yes No No abstract final class No No No No No mixin class Yes Yes Yes Yes No base mixin class Yes Yes No Yes No abstract mixin class No Yes Yes Yes No abstract base mixin class No Yes No Yes No mixin No No Yes Yes No base mixin No No No Yes No

DevTools Section 01 41 What's new in Dart and Flutter ● Perfetto ● Memory Diff

Material 3 brings new widgets to help create beautiful designs for every device that Flutter supports. Layouts can be quite different depending on the platform they are running on and what input devices are currently active. Deep dive into the various ways you can create with adaptive layouts, expressive color and typography, and theming the many widgets available for Material 3. Theming does not have to be hard when a design can be broken down into reusable widgets. Design for every device with Flutter and Material 3 Section 02 42

Section 02 43 Flutter and Material 3 https://github.com//flutter/flutter/issues/91605 Access: 2023-03-28

Section 02 44 Flutter and Material 3 https://github.com//flutter/flutter/issues/91605 Access: 2023-07-22

Section 02 45 Flutter and Material 3 https://flutter.github.io/samples/web/material_3_demo/#/ Access: 2023-07-22

Section 02 46 Flutter and Material 3 https://rydmike.com/flexcolorscheme/themesplayground-v7-2/#/

Section 02 47 Flutter and Material 3 Making Material 3 the default 2023-07-13 기준 Master channel: 현재 적용 완료 Beta 채널: 8월 중 적용 (현재 적용된것으로 보임) Stable 채널: beta 채널 적용 이후 https://github.com/flutter/flutter/issues/127064 Access: 2023-07-22

return MaterialApp( title: 'Flutter Demo', theme: ThemeData( useMaterial3: true, ), home: const MyHomePage(title: 'Flutter Demo Home Page'), ); 48

Section 02 49 Flutter and Material 3 Material 3 Color Scheme

return MaterialApp( title: 'Flutter Demo', theme: ThemeData( colorScheme: ColorScheme.fromSeed( seedColor: Colors.deepPurple, ), useMaterial3: true, ), home: const MyHomePage(title: 'Flutter Demo Home Page'), ); 50

Section 02 51 Flutter and Material 3 dynamic_color https://pub.dev/packages/dynamic_color Access: 2023-07-22

Section 02 52 Flutter and Material 3 Typography

@Deprecated( 'Use displayLarge instead. ' 'This feature was deprecated after v3.1.0-0.0.pre.', ) TextStyle? headline1, @Deprecated( 'Use displayMedium instead. ' 'This feature was deprecated after v3.1.0-0.0.pre.', ) TextStyle? headline2, 53

Section 02 54 Flutter and Material 3 Typography https://pub.dev/packages/google_fonts Access: 2023-07-22

Section 02 55 Flutter and Material 3 Adaptive scaffold https://pub.dev/packages/flutter_adaptive_scaffold Access: 2023-07-22

Firebase provides you with APIs and tools to build, release, and operate full-stack apps for many platforms, including Flutter. In this session you will learn about the latest improvements that we made and what we’re working on for the future. What's new in Firebase's Flutter Section 03 56

● For Cloud and Firebase, that means offering packages like FlutterFire that make it easy to complement Flutter apps with our cloud backend, as well as documentation and guidance for hosting Dart in the cloud. It includes supporting Cloud account teams who are selling full-stack solutions to their customers. ● For Android, we help customers “shift left”: giving iOS developers a path to build on a supported Google stack that also targets Android. This also includes the sizable revenue stream we are building for in-app purchases with Play. In 2023, we will continue to enthusiastically build pathways to help developers light up on Android, in collaboration with the Android team. ● For Ads, we continue to partner on breadth opportunities, with first-party support for a broad set of mobile ads formats, targeted campaigns around casual gaming, and product investments around deep-linking. In 2023, we will broadly roll out our work with news publishers to offer a custom toolkit that incorporates ads and Firebase. ● For Geo, we will partner with them to grow our maps plugin, including adding support for client-side directions, and integration into the Google Maps developer docs. Flutter as an on-ramp for Google Section 03 57 Source: Flutter 2023 Strategy What's new in Firebase's Flutter Strategy

Document Update Section 03 58 https://firebase.flutter.dev/ https://firebase.google.com/docs/flutter/setup?hl=ko&platform=ios What's new in Firebase's Flutter

Package Support Section 03 59 What's new in Firebase's Flutter ● Firebase Crashlytic 개선 Access: 2023-07-22

Platform Support Section 03 60 What's new in Firebase's Flutter ● FlutterFire CLI 업데이트 ● Firbase support for windows development workflows ● C++ ● Desktop Support

Platform Support Section 03 61 https://github.com/FirebaseExtended/flutterfire_desktop Access: 2023-07-22 What's new in Firebase's Flutter dependencies: firebase_auth: ^3.1.5 firebase_auth_desktop: ^0.1.1-dev.0 firebase_core: ^1.9.0 firebase_core_desktop: ^0.1.1-dev.0

Flutter’s new rendering engine was developed with the goal of eliminating shader compilation jank and providing predictable performance. This talk will discuss the design of Impeller and how it fits into the broader architecture for Flutter. This includes a tour of Impeller’s sub frameworks, and a demonstration of how lower level APIs are used in Flutter applications. The session will also discuss how Impeller enables new experiences, like 3D support. Flutter's new rendering engine Section 04 62

Section 04 63 Flutter's new rendering engine Flutter Framework Flutter Engine Dart Runtime Platform Channel Renderer Embedder System Events

Section 04 64 Flutter's new rendering engine

Section 04 65 Flutter's new rendering engine

Section 04 66 Flutter's new rendering engine What’s Jank? ● Slow Frame ● FPS (Frame per second ) = 초당 프레임 수 ● 60 FPS 는 1초에 60 개의 프레임을 출력 ● 1개의 프레임을 렌더링하는데 걸리는 속도는? ○ 16ms 내외로 처리가 가능해야함 60fps의 경우 16ms 내로 처리하는지 못하는 경우 중간 중간 프레임 처리를 놓치는 경우 UI Jank, 프레임 드롭

Section 04 67 Flutter's new rendering engine ● Engine 개발의 Jank관련 내역은 ● 2015년도에도 도출되었던 내역. ● Google Nust Hub ○ Flutter ● GPay ○ Flutter

Section 04 68 Flutter's new rendering engine My app sits on the splash screen for about 6 seconds on first launch, which is a really poor first impression for my users.

Skia’s shader generation and compilation happens in sequence with the frame workload. Impeller generates and compiles all necessary shaders when we build the Flutter Engine. Therefore apps running on Impeller already have all the shaders they need, and the shaders can be used without introducing jank into animations. Skia Impeller What’s Shader Compilation Jank? Section # 69 Flutter's new rendering engine

Impeller Section 04 70 Flutter's new rendering engine ● A rendering engine for Flutter. ● Replaces Skia in Flutter Engine. Impeller available by default on iOS

Impeller Section 04 71 Flutter's new rendering engine

Impeller Section 04 72 Flutter's new rendering engine Per Vertex Shader Per pixel Shader o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o

o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o Impeller Section 04 73 Flutter's new rendering engine o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o

// info.plist FLTEnableImpeller 74

// AndroidManifest.xml // under tag 75

Flutter apps on the web are loading faster and have better integration with HTML in the latest release. We will also be sharing our progress on compiling Flutter web apps to WebAssembly. Evolving Flutter's support for the web Section 05 76

1. Enable "hot reload" (not just "hot restart") for Flutter Web #53041 2. Improve the indexability (SEO) of Flutter apps on the web (#46789) 3. Server-side rendering for Flutter web (#47600) 4. main.dart.js is too large #46589 Flutter for the Web Section 05 77 ● Flutter as the first of a new breed of frameworks that target WebGL and Wasm and leave HTML behind. ● Flutter for web, as currently designed, is fundamentally a client-side technology. ● Dart is compiled to JS (or maybe one day Wasm, we're looking into that in the coming year).

1. Compress canvaskit size 2. Compress font size 3. Element Embedding 4. WASM(WebAssembly) 5. Fragment Shaders for Web Flutter for the Web Section 05 78

Section 05 79 Evolving Flutter's support for the web

Section 05 80 로컬에서 기본 카운터 앱 로딩 0.3~0.4초 정도 서버, 인터넷 환경에 따라 다를 수 있음. Evolving Flutter's support for the web

jaichang@PARKui-MacBookPro untitled1 % flutter build web --release Font asset "CupertinoIcons.ttf" was tree-shaken, reducing it from 283452 to 1272 bytes (99.6% reduction). Tree-shaking can be disabled by providing the --no-tree-shake-icons flag when building your app. Font asset "MaterialIcons-Regular.otf" was tree-shaken, reducing it from 1645184 to 7652 bytes (99.5% reduction). Tree-shaking can be disabled by providing the --no-tree-shake-icons flag when building your app. 81

Section 05 82 Evolving Flutter's support for the web

Section 05 83 Evolving Flutter's support for the web Source: FLUTTER, DART, AND WASM-GC: A NEW MODEL FOR WEB APPLICATIONS

Section 05 84 Evolving Flutter's support for the web Source: FLUTTER, DART, AND WASM-GC: A NEW MODEL FOR WEB APPLICATIONS

Section 05 85 Evolving Flutter's support for the web Source: FLUTTER, DART, AND WASM-GC: A NEW MODEL FOR WEB APPLICATIONS

// preview Wasm and WebAssembly garbage collection (WasmGC) in the master channel. jaichang@PARK-MacBookPro % flutter channel master % flutter create web_wasm % cd web_wasm 86

// build a web application with Wasm jaichang@PARK-MacBookPro web_wasm % flutter build web --wasm 87

Section 05 88 Evolving Flutter's support for the web

Fragment Shaders for the Web Section 05 89 https://codelabs.developers.google.com/codelabs/flutter-nex t-gen-uis?hl=ko#0 Shader Support Evolving Flutter's support for the web

Fragment Shaders for the Web Section 05 90 Shader Support Evolving Flutter's support for the web

Learn how Flutter on the Raspberry Pi enables makers to build exciting new embedded user interfaces. The Raspberry Pi was introduced as a tool to teach computer science, but since its introduction has been a staple in every maker’s toolbox. It’s been used as the basis for maker projects such as IoT devices, game emulators, and kiosks. So this is the answer to "What would a Flutter & Raspberry Pi game console look like?" Flutter, Dart, and Raspberry Pi Section 06 91

Section 06 92 Flutter, Dart, and Raspberry Pi Raspberry Pi BCM2835 Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.8GHz BCM54213PE Samsung LPDDR4 RAM, Cypress CYW43455

Section 06 93 Flutter, Dart, and Raspberry Pi Raspberry Pi ● OS(운영체제)를 올릴 수 있는 하드웨어 ● 충분한 메모리 ● 모니터 & 디스플레이 연결이 가능 ● 소형 데스크톱 컴퓨터

Section 06 94 Flutter, Dart, and Raspberry Pi Google Nest Hub Fuchsia OS Flutter Embedded System

Section 06 95 Flutter, Dart, and Raspberry Pi 5-6만원대

Section 06 96 Flutter, Dart, and Raspberry Pi ● Flutter ● Flame ● Doodle Dash

Section 06 97 Flutter, Dart, and Raspberry Pi 디스플레이 각종 버튼 사용자 입력 OS Flutter App 버튼 동작 인식

Section 06 98 Flutter, Dart, and Raspberry Pi Access 2023-07-22

// Get the current button state final button = gpio.input(11, Pull.up); print('Button state: ${await button.value}'); 99

final subscription = button.values .transform(Debouncer(lastValue, debounce)) .listen((bool newValue) { print('New button state: $newValue'); }); 100

Section 06 101 Flutter, Dart, and Raspberry Pi Flutter Embedded https://youtu.be/jW3pqIpQtQE 2022-03-05

Section 06 102 Flutter, Dart, and Raspberry Pi Flutter Embedded https://youtu.be/jW3pqIpQtQE 2022-03-05

Section 06 103 Flutter, Dart, and Raspberry Pi Flutter 💙 Embedded https://festa.io/events/3780 Upcoming

Release SDK 3.13 Section 07 104 Beta

Section 07 105 Release 3.13 beta Framework ● Update ListTile text defaults to use ColorScheme ○ #128581 ● Add onSubmitted property to SearchBar ○ #129365 ● [framework] Add textField OCR support for framework side ○ #96637 Release SDK 3.13 Beta

Section 07 106 Release 3.13 beta Desktop ● [Impeller] allowing enabling Impeller on macOS. ○ in flutter/engine#42639 ● [macOS] Add platformview creation parameter support ○ in flutter/engine#42607 Release SDK 3.13 Beta

Section 07 107 Release SDK 3.13 Release 3.13 beta Web ● Remove /#/ from home page URL ○ flutter/engine#42598 ● Move webOnlyAssetManager to dart:ui_web ○ flutter/engine#42642 ● Move web-only initialization APIs to dart:ui_web ○ flutter/engine#43111 Beta

Section 08 108 Multi-Window

Section 08 109 Multi-Window https://docs.google.com/document/d/1Z7Qrb08dOnfB8IxPgsyujVn4MsDcYPUUku9CeF70_S0/edit#heading=h.xza97bbt7w4f Access 2023-07-22

Section 08 110 Multi-Window Access 2023-07-22

Summary Section 09 111

Section 09 112 ● Dart 3 ○ Record & Patterns ○ Class Modifiers ● Flutter 3.10 ○ Material 3 ○ Shader support web ○ Impeller available by default on iOS ● FlutterFire (Firebase) ○ New Documents ○ Update Firebase Crashlytics ● Flutter Web 💜 Wasm ○ Master Channel ○ Wasm GC ○ Fragment Shaders Summary

Thank You JaiChang Park he/him GDG Golang Korea / Flutter Seoul 113