Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Ready for Async Rendering
Search
koba04
April 19, 2018
Programming
6
1.6k
Ready for Async Rendering
Scramble! #1 Frontend
https://folio.connpass.com/event/82816/
koba04
April 19, 2018
Tweet
Share
More Decks by koba04
See All by koba04
フロントエンドの現在地とこれから
koba04
10
5.1k
Standing on the shoulders of giants
koba04
0
2.8k
React/Next によるアプリケーション開発のこれから
koba04
61
17k
フロントエンド刷新をプロジェクトとして進める際に気をつけていること
koba04
3
1.9k
How useEvent would change our applications
koba04
1
3k
kintoneフロントエンド刷新によるモノリスからの脱却とその先に目指す未来
koba04
3
15k
Make it Declarative with React
koba04
0
1.7k
Ready for React in 2019
koba04
2
1.7k
Algorithms in React
koba04
14
17k
Other Decks in Programming
See All in Programming
自分のために作ったアプリが、グローバルに使われるまで / Indie App Development Lunch LT
pixyzehn
1
160
Vibe Codingをせずに Clineを使っている
watany
17
6.3k
Signal-Based Data FetchingWith the New httpResource
manfredsteyer
PRO
0
180
PHPバージョンアップから始めるOSSコントリビュート / how2oss-contribute
dmnlk
1
1k
音声プラットフォームのアーキテクチャ変遷から学ぶ、クラウドネイティブなバッチ処理 (20250422_CNDS2025_Batch_Architecture)
thousanda
0
180
アプリを起動せずにアプリを開発して品質と生産性を上げる
ishkawa
0
2.8k
Java 24まとめ / Java 24 summary
kishida
3
500
PHP で学ぶ OAuth 入門
azuki
1
190
Compose Hot Reload is here, stop re-launching your apps! (Android Makers 2025)
zsmb
1
510
AI Agents with JavaScript
slobodan
0
230
Sharing features among Android applications: experience feedback
jbvincey
0
110
「”誤った使い方をすることが困難”な設計」で良いコードの基礎を固めよう / phpcon-odawara-2025
taniguhey
0
140
Featured
See All Featured
Rails Girls Zürich Keynote
gr2m
94
13k
GraphQLとの向き合い方2022年版
quramy
46
14k
Thoughts on Productivity
jonyablonski
69
4.6k
Git: the NoSQL Database
bkeepers
PRO
430
65k
Scaling GitHub
holman
459
140k
Being A Developer After 40
akosma
91
590k
Stop Working from a Prison Cell
hatefulcrawdad
268
20k
What’s in a name? Adding method to the madness
productmarketing
PRO
22
3.4k
A Tale of Four Properties
chriscoyier
158
23k
Understanding Cognitive Biases in Performance Measurement
bluesmoon
29
1.6k
How to Create Impact in a Changing Tech Landscape [PerfNow 2023]
tammyeverts
52
2.4k
Designing Experiences People Love
moore
141
24k
Transcript
3FBEZGPS"TZOD3FOEFSJOH 4DSBNCMF !LPCB
None
"HFOEB w 8IBUJT"TZOD3FOEFSJOH w -JGFDZDMF.FUIPET4USJDU.PEF w 5JNF4MJDJOH w 3FBDU4VTQFOTF
w "QQFOEJY v16.3 Changes
8IBUJT"TZOD3FOEFSJOH
w 3FBDU'JCFSJTBOVOJUPGXPSL 㲈3FBDU&MFNFOU w *UJTQPTTJCMFUPTUPQBOESFTVNFVQEBUFT 3FDBQ3FBDU'JCFS FiberA FiberB FiberD
FiberE Commit all SideEffects Idle Time Idle Time Idle Time SideEffect SideEffect Host (DOM) FiberC Render Phase Commit Phase
w 3FOEFS1IBTFʜ"TZOD w $PNNJU1IBTFʜ4ZOD 3FDBQ3FBDU'JCFS FiberA FiberB FiberD FiberE Commit
all SideEffects Idle Time Idle Time Idle Time SideEffect SideEffect Host (DOM) FiberC Async Sync
4VTQFOEBOE3FTVNF FiberA FiberB FiberA FiberC Commit Low Priority Sync Priority
Commit FiberA FiberB FiberC Low Priority Reuse Interrupt Suspend
-JGFDZDMF.FUIPET
$IBOHFTGPSMJGFDZDMFNFUIPET http://blog.koba04.com/post/2018/04/04/react-v163-changes/
w $BMMFEBU3FOEFS1IBTF w 3FUVSOBQBSUJBMTUBUFCBTFEPOOFYU1SPQT w TUBUJDHFU%FSJWFE4UBUF'SPN1SPQT static getDerivedStateFromProps(nextProps, prevState) {
if (nextProps.category !== prevState.category) { return { data: null, category: null }; } return null; } componentDidUpdate() { if (this.state.category == null) { fetchData(this.props.category).then((data) => { this.setState({category: this.props.category, data}); }); }
w $BMMFEBU$PNNJU1IBTF w 3FUVSOBTOBQTIPU BOZ CFGPSFVQEBUFUIF)PTU w UIFTOBQTIPUJTQBTTFEUPDPNQPOFOU%JE6QEBUF HFU4OBQTIPU#FGPSF6QEBUF getSnapshotBeforeUpdate()
{ return { scrollHeight: document.body.scrollHeight, scrollTop: document.body.scrollTop, }; } componentDidUpdate(prevProps, prevState, snapshot) { const {body} = document; const {scrollTop, scrollHeight} = snapshot; body.scrollTop = scrollTop + (body.scrollHeight - scrollHeight); }
https://reactjs.org/blog/2018/03/27/update-on-async-rendering.html#examples
https://github.com/facebook/react/tree/master/packages/create-subscription
4USJDU.PEF
w *EFOUJGZJOHDPNQPOFOUTVOTBGFMJGFDZDMFT w 8BSOJOHBCPVUMFHBDZTUSJOHSFG"1*VTBHF w %FUFDUJOHVOFYQFDUFETJEFF⒎FDUT 4USJDU.PEF const {StrictMode} =
React; const App = () => ( <StrictMode> <Header /> <Main /> <Footer /> </StrictMode> );
/FX$BQBCJMJUJFT
https://reactjs.org/blog/2018/03/01/sneak-peek-beyond-react-16.html
5JNF4MJDJOH
w #MPDLJOH6*UISFBEJTBOBXGVMFYQFSJFODF w 5IFSFBSFNBOZQFPQMFXIPVTFMPXQPXFSEFWJDFT w 8IZOPUEFCPVODFPSUISPUUMF 5IFBOTXFSJTʜ w SFRVFTU*EMF$BMMCBDL 5JNF4MJDJOH
<AsyncMode> <FilterInput onChange={value => { ReactDOM.flushSync(() => this.setState({value})); this.setState({data: this.filterData(value)}); }} /> </AsyncMode>
https://koba04.github.io/react-fiber-resources/examples/ Async Update Sync Update
None
https://zeit.co/blog/domains-search-web
3FBDU4VTQFOTF
https://github.com/facebook/react/pull/12279
w 3FBDU4VTQFOTFJTBGFBUVSFUPIBOEMFBTZODVQEBUFT w )5513FRVFTU w %ZOBNJD-PBEJOH w )BOEMJOHBTZODISPOPVTVQEBUFTBSFTPIBSEʜ w 4UBSU-PBEJOH
"1*4VDDFTT &SSPSʜ w .BOZMPBEJOHTQJOOFST KBOLCZBGBTUSFTQPOTF 3FBDU4VTQFOTF
3FBDU4VTQFOTF "1*XJMMCFDIBOHFE import SimpleCacheProvider from ‘simple-cache-provider’; const cache = SimpleCacheProvider.createCache();
const userFetcher = id => SimpleCacheProvider.createResource(id => fetch(`/api/users/${id}`).then(res => res.json()); )(cache, id); const User = props => { const user = userFetcher.read(props.id); return <div>{user.name}</div>; }; const Fallback = props => ( <React.Timeout ms={props.timeout}> {didExpire => didExpire ? props.placeholder : props.children} </React.Timeout> ); <Fallback placeholder=“Loading…” timeout={200}> <User id={100} /> </Fallback>
3FBDU4VTQFOTF "1*XJMMCFDIBOHFE import SimpleCacheProvider from ‘simple-cache-provider’; const cache = SimpleCacheProvider.createCache();
const routeFetcher = Component => SimpleCacheProvider.createResource(Component => import(Component).then(module => module.default); )(cache, Component); const UserPage = () => { const Component = routeFetcher.read(‘./pages/User’); return <Component />; }; const Fallback = props => ( <React.Timeout ms={props.timeout}> {didExpire => didExpire ? props.placeholder : props.children} </React.Timeout> ); <Fallback placeholder=“Loading…” timeout={1000}> <UserPage /> </Fallback>
Empty Pending Resolved Rejected read or preload throw promise return
value from cache Cache load
w 3FBDU4VTQFOTFJTCBTFEPO&SSPS#PVOEBSJFT UIPVHI XIJDIUISPXT1SPNJTFJOTUFBEPG&SSPS )PXEPFT3FBDU4VTQFOTFXPSL User Fallback Timeout throw Promise!
(suspend) timeout render with fetched Data (resume)
https://github.com/facebook/react/pull/12201
w 5IF"1*JTOPUpOBM"1* NJHIUCFDIBOHFE w *IFBSESFOEFSGVODUJPONVTUOPUIBWFBOZTJEFF⒎FDUT w 3FBDU4VTQFOTFPO443SFOEFSFS w
1SFSFOEFSBOEQSFMPBEJOHXJUIIJEEFOQSPQT w "XFTPNF8IFODBO*VTF3FBDU4VTQFOTF w .BZCFJOʜ 3FBDU4VTQFOTF
"QQFOEJY
/FX$POUFYU"1* const LangContext = React.createContext(‘en’); const ThemeContext = React.createContext(‘dark’); const
App = () => ( <LangContext.Provider value=“en”> <ThemeContext.Provider value=“dark”> <Child> <LangContext.Consumer> {lang => ( <ThemeContext.Consumer> {theme => ( <button className={theme}> {getMessage(‘click’, lang)} </button> )} </ThemeContext.Consumer> )} </LangContext.Consumer> </Child> </ThemeContext.Provider> </LangContext.Provider> );
w )BSEUPUZQFDIFDLJOH w TIPVME$PNQPOFOU6QEBUFNJHIUCSFBLUIFVQEBUF 1SPCMFNTPGMFHBDZ$POUFYU"1* GrandChild Child Parent ThemeContext Brown
-> Orange shouldComponentUpdate return false;
w 0QUJNJ[FUIFVQEBUFTGPS$POUFYUWBMVF w 3FBDUVTFTCJUXJTFPQFSBUPSJUTJOUFSOBMT 0CTFSWFE#JUT VOTUBCMF⚠ const StoreContext = React.createContext(null,
(prev, next) => { let changedBits = 0; if (prev.foo !== next.foo) changedBits |= 0b01; if (prev.bar !== next.bar) changedBits |= 0b10; return changedBits; }); // changedBits & unstable_observedBits !== 0 <StoreContext.Consumer unstable_observedBits={0b01}> {({foo}) => <div>{foo}</div> </StoreContext.Consumer> <StoreContext.Consumer unstable_observedBits={0b10}> {({bar}) => <div>{bar}</div> </StoreContext.Consumer>
https://medium.com/@koba04/a-secret-parts-of-react-new-context-api-e9506a4578aa
w 3FEVYBOE/FX$POUFYUBSFEJ⒎FSFOUMBZFST w SFBDUSFEVYNJHIUCFDIBOHFEXJUI/FX$POUFYU"1* w IUUQTHJUIVCDPNSFBDUKTSFBDUSFEVYQVMM w 8IZBSFZPVVTJOH3FEVY /FX$POUFYUBOE3FEVY
5IBOLT TQFBLFSEFDLDPNLPCB