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
5.3k
Standing on the shoulders of giants
koba04
0
2.9k
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
3.1k
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
1.8k
Ready for React in 2019
koba04
2
1.7k
Algorithms in React
koba04
14
17k
Other Decks in Programming
See All in Programming
CloudflareのChat Agent Starter Kitで簡単!AIチャットボット構築
syumai
2
510
請來的 AI Agent 同事們在寫程式時,怎麼用 pytest 去除各種幻想與盲點
keitheis
0
120
How Android Uses Data Structures Behind The Scenes
l2hyunwoo
0
480
Tool Catalog Agent for Bedrock AgentCore Gateway
licux
7
2.5k
複雑なフォームに立ち向かう Next.js の技術選定
macchiitaka
2
200
Cache Me If You Can
ryunen344
2
3k
Amazon RDS 向けに提供されている MCP Server と仕組みを調べてみた/jawsug-okayama-2025-aurora-mcp
takahashiikki
1
110
Reading Rails 1.0 Source Code
okuramasafumi
0
250
Android 16 × Jetpack Composeで縦書きテキストエディタを作ろう / Vertical Text Editor with Compose on Android 16
cc4966
2
260
AI Coding Agentのセキュリティリスク:PRの自己承認とメルカリの対策
s3h
0
230
The Past, Present, and Future of Enterprise Java
ivargrimstad
0
400
AIでLINEスタンプを作ってみた
eycjur
1
230
Featured
See All Featured
Side Projects
sachag
455
43k
XXLCSS - How to scale CSS and keep your sanity
sugarenia
248
1.3M
The Straight Up "How To Draw Better" Workshop
denniskardys
236
140k
Put a Button on it: Removing Barriers to Going Fast.
kastner
60
4k
Testing 201, or: Great Expectations
jmmastey
45
7.7k
GitHub's CSS Performance
jonrohan
1032
460k
The Language of Interfaces
destraynor
161
25k
ReactJS: Keep Simple. Everything can be a component!
pedronauck
667
120k
Build your cross-platform service in a week with App Engine
jlugia
231
18k
Music & Morning Musume
bryan
46
6.8k
Distributed Sagas: A Protocol for Coordinating Microservices
caitiem20
333
22k
Rebuilding a faster, lazier Slack
samanthasiow
83
9.2k
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