Styling React Components
with glamorous 💄
Kent C. Dodds
Utah
1 wife, 3 kids
PayPal, Inc.
@kentcdodds
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Please Stand...
if you are able
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What this talk is
- Brief intro to CSS-in-JS
- Story of why glamorous is a thing
- Elicit feedback from you all
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What this talk is not
- An attempt to get you to use glamorous
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Let's
Get
STARTED!
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Our Component:
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JavaScript + HTML = JSX
class Toggle extends Component {
state = { toggledOn: false };
handleToggleClick = () => {
this.setState(
({ toggledOn }) => ({ toggledOn: !toggledOn }),
(...args) => {
this.props.onToggle(this.state.toggledOn);
},
);
};
render() {
const { children } = this.props;
const { toggledOn } = this.state;
const active = toggledOn ? 'active' : '';
return (
<button
className={`btn btn-primary ${active}`}
onClick={this.handleToggleClick}
>
{children}
</button>
);
}
}
export default Toggle;
Components!
import { PrimaryButton } from './css-buttons';
class Toggle extends Component {
state = { toggledOn: false };
handleToggleClick = () => {
this.setState(
({ toggledOn }) => ({ toggledOn: !toggledOn }),
(...args) => {
this.props.onToggle(this.state.toggledOn);
},
);
};
render() {
const { children } = this.props;
const { toggledOn } = this.state;
const active = toggledOn ? 'active' : '';
return (
<PrimaryButton
active={active}
onClick={this.handleToggleClick}
>
{children}
</PrimaryButton>
);
}
}
export default Toggle;
Components!
function AppButton({ className = '', active, ...props }) {
return (
<button
className={`btn ${className} ${active ? 'active' : ''}`}
{...props}
/>
);
}
function PrimaryButton({ className = '', ...props }) {
return <AppButton className={`btn-primary ${className}`} {...props} />;
}
export default AppButton;
export { PrimaryButton };
CSS? Where are the styles?
CSS? 🤔
.btn {
display: inline-block;
font-weight: 400;
line-height: 1.25;
text-align: center;
white-space: nowrap;
vertical-align: middle;
user-select: none;
border: 1px solid transparent;
padding: .5rem 1rem;
font-size: 1rem;
border-radius: .25rem;
transition: all .2s ease-in-out;
}
.btn.btn-primary {
color: #fff;
background-color: #0275d8;
border-color: #0275d8;
}
.btn-primary:hover, .btn-primary.active {
background-color: #025aa5;
border-color: #01549b;
}
- Conventions?
- Who's using these styles?
- Can I delete these styles?
- Can I change these styles?
CSS?
The P2P Funnel Page
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Our CSS...
// import styles for funnel pages control, T2, T3, T4 and T5
.funnel_control,
.funnel_2A,
.funnel_2B,
.funnel_3,
.funnel_4,
.funnel_5_2dot5,
.funnel_5_xb,
.funnel_overseas {
@import "./funnel";
}
// import styles for funnel page T6 and variants
.funnel_6_2dot5,
.funnel_6_xb,
.funnel_7_xb,
.funnel_8_xb,
.funnel_9_xb,
.funnel_10_xb,
.funnel_11_xb,
.funnel_12_xb,
.funnel_7_gb {
@import "./funnelT6";
}
// import styles for ppme entry on funnel pages T5, T6, T7 and T8
.funnel_5_2dot5,
.funnel_5_xb,
.funnel_6_2dot5,
.funnel_6_xb,
.funnel_7_xb,
.funnel_8_xb,
.funnel_9_xb,
.funnel_10_xb,
.funnel_11_xb,
.funnel_12_xb,
.funnel_7_gb {
@import './block-group-entry';
@import './ppme-entry/ppme-entry';
@import './ppme-entry/ppme-entry-buttons';
@import './ppme-entry/ppme-entry-interaction';
}
// ...etc
What impact will my change have elsewhere?
Components
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Default
Styled
Unstyled
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Focus
Toggled
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Components
What is a UI component made of?
HTML
CSS
JS
Component
Enter CSS-in-JS
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Remember our CSS?
<style>
.btn {
display: inline-block;
font-weight: 400;
line-height: 1.25;
text-align: center;
white-space: nowrap;
vertical-align: middle;
user-select: none;
border: 1px solid transparent;
padding: .5rem 1rem;
font-size: 1rem;
border-radius: .25rem;
transition: all .2s ease-in-out;
}
.btn.btn-primary {
color: #fff;
background-color: #0275d8;
border-color: #0275d8;
}
.btn-primary:hover, .btn-primary.active {
background-color: #025aa5;
border-color: #01549b;
}
</style>
<script>
function AppButton({ className = '', active, ...props }) {
return (
<button
className={`btn ${className} ${active ? 'active' : ''}`}
{...props}
/>
);
}
function PrimaryButton({ className = '', ...props }) {
return <AppButton className={`btn-primary ${className}`} {...props} />;
}
export default AppButton;
export { PrimaryButton };
</script>
import { css } from 'glamor';
const appButtonClassName = css({
display: 'inline-block',
fontWeight: '400',
lineHeight: '1.25',
textAlign: 'center',
whiteSpace: 'nowrap',
verticalAlign: 'middle',
userSelect: 'none',
border: '1px solid transparent',
padding: '.5rem 1rem',
fontSize: '1rem',
borderRadius: '.25rem',
transition: 'all .2s ease-in-out',
});
const highlightStyles = {
backgroundColor: '#025aa5',
borderColor: '#01549b',
};
const primaryButtonClassName = css({
color: '#fff',
backgroundColor: '#0275d8',
borderColor: '#0275d8',
':hover': highlightStyles,
});
const activeClassName = css(highlightStyles);
function AppButton({ className = '', active, ...props }) {
return (
<button
className={`${appButtonClassName} ${className} ${active ? activeClassName : ''}`}
{...props}
/>
);
}
function PrimaryButton({ className = '', ...props }) {
return (
<AppButton
className={`${primaryButtonClassName} ${className}`}
{...props}
/>
);
}
export default AppButton;
export { PrimaryButton };
Enter glamorous 💄
import glamorous from 'glamorous';
const AppButton = glamorous.button({
display: 'inline-block',
fontWeight: '400',
lineHeight: '1.25',
textAlign: 'center',
whiteSpace: 'nowrap',
verticalAlign: 'middle',
userSelect: 'none',
border: '1px solid transparent',
padding: '.5rem 1rem',
fontSize: '1rem',
borderRadius: '.25rem',
transition: 'all .2s ease-in-out',
});
const highlightStyles = {
backgroundColor: '#025aa5',
borderColor: '#01549b',
};
const PrimaryButton = glamorous(AppButton)(
{
color: '#fff',
backgroundColor: '#0275d8',
borderColor: '#0275d8',
':hover': highlightStyles,
},
({ active }) => (active ? highlightStyles : null),
);
export default AppButton;
export { PrimaryButton };
Solving CSS problems
- Global Namespace ✅
- Dependencies ✅
- Dead Code Elimination ✅
- Minification ✅
- Sharing Constants ✅
- Non-deterministic Resolution ✅
- Isolation ✅
jest-glamor-react
📸
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+ Our codebase now
function Consumer(props) {
return (
<FunnelPage>
<FunnelLinkGroup title={i18n('flexible.group.send')}>
<ConsumerFunnelLink {...funnelProps.buyLink(props)} />
<ConsumerFunnelLink {...funnelProps.sendLink(props)} />
<ConsumerFunnelLink {...funnelProps.xbLink(props)} />
<ConsumerFunnelLink {...funnelProps.giftLink(props)} />
<ConsumerFunnelLink {...funnelProps.massPaymentLink(props)} />
</FunnelLinkGroup>
<FunnelLinkGroup {...funnelProps.requestGroup(props)}>
<ConsumerFunnelLink {...funnelProps.requestLink(props)} />
<ConsumerFunnelLink {...funnelProps.invoiceLink(props)} />
<ConsumerFunnelLink {...funnelProps.poolsLink(props)} />
<ConsumerFunnelLink {...funnelProps.ppmeLink(props)} />
</FunnelLinkGroup>
</FunnelPage>
)
}
// funnelProps are pretty neat-o, here's the buy.js one
import { canSendMoney } from './utils'
const staticProps = {
id: 'nemo_buyLink',
icon: 'register',
descriptionKey: 'flexible.buy.description',
badgeHTMLKey: 'flexible.buy.protectionBadge',
}
export default buy
function buy(props: FunnelProps): {} {
const { country, paymentTypes, redirectToClassicInfo: { shouldRedirectToClassic, classicSendUrl } } = props
const shouldRender = canSendMoney(props) && paymentTypes.includes('PURCHASE')
if (!shouldRender) {
return { shouldRender }
}
const titleKey = country === 'DE' ? 'iWantTo.payDE' : 'flexible.buy.title'
const dynamicProps = shouldRedirectToClassic ? ({
titleKey,
href: classicSendUrl,
name: '',
'data-pagename': '',
'data-pagename2': '',
}) : ({
titleKey,
to: '/myaccount/transfer/buy',
name: 'goodsStart',
'data-pagename': 'main:walletweb:transfer:buy:start',
'data-pagename2': 'main:walletweb:transfer:buy:start:::',
})
return { ...staticProps, ...dynamicProps }
}
// and tests are pretty cool:
import { propsTester } from './helpers/utils'
import buyLink from '../buy'
const defaults = {
input: {
businessAccountInfo: { isSecondaryUser: false, privileges: [] },
paymentTypes: ['PURCHASE'],
redirectToClassicInfo: {
shouldRedirectToClassic: false,
},
},
result: {
id: 'nemo_buyLink',
icon: 'register',
descriptionKey: 'flexible.buy.description',
badgeHTMLKey: 'flexible.buy.protectionBadge',
},
}
propsTester({
fn: buyLink,
fnTests: [
{
input: { ...defaults.input },
result: {
...defaults.result,
titleKey: 'flexible.buy.title',
to: '/myaccount/transfer/buy',
name: 'goodsStart',
'data-pagename': 'main:walletweb:transfer:buy:start',
'data-pagename2': 'main:walletweb:transfer:buy:start:::',
},
},
{
input: {
...defaults.input,
businessAccountInfo: {
isSecondaryUser: true,
privileges: ['send_money'],
},
},
result: {
...defaults.result,
titleKey: 'flexible.buy.title',
to: '/myaccount/transfer/buy',
name: 'goodsStart',
'data-pagename': 'main:walletweb:transfer:buy:start',
'data-pagename2': 'main:walletweb:transfer:buy:start:::',
},
},
]
})
// glossing over some details...
function ConsumerFunnelLink() {
return (
<FunnelLink shouldRender={shouldRender}>
<Anchor verticalSpacing={verticalSpacing} {...anchorProps}>
<Icon icon={icon} svg={svg} />
<Title>{title}</Title>
<ConditionalDescription shouldRender={renderDescription}>
{description}
</ConditionalDescription>
</Anchor>
<DesktopBadge filler={!subtext}>{badge}</DesktopBadge>
<ConsumerSubtext>{subtext}</ConsumerSubtext>
</FunnelLink>
)
}
// and here's the Anchor component:
import glamorousLink from '../../component-factories/glamorous-link'
import { mediaQueries } from '../../../../styles'
import {
spaceChildrenVertically,
spaceChildrenHorizontally,
} from '../../css-utils'
const { phoneLandscapeMin: desktop, phoneLandscapeMax: mobile } = mediaQueries
const onAttention = '&:hover, &:focus, &:active'
const Anchor = glamorousLink(
{
display: 'flex',
'& > *:last-child': {
flex: '0 1 auto',
},
minHeight: 0, // firefox weirdness
[onAttention]: {
textDecoration: 'none',
'& .funnel-description': {
color: '#333333',
},
},
[mobile]: {
padding: '22px 12px 20px 12px',
flexDirection: 'row',
'& > *:last-child': {
flex: 1,
},
...spaceChildrenHorizontally(30),
},
[desktop]: {
marginTop: 12,
flex: 1,
flexDirection: 'column',
justifyContent: 'flex-start',
[onAttention]: {
'& .icon, & .icon-svg': {
color: '#ffffff',
backgroundColor: '#0070ba',
},
},
},
},
({ verticalSpacing = 10 }) => ({
[desktop]: {
...spaceChildrenVertically(verticalSpacing),
},
}),
)
export default Anchor
Now it's a funnel
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And code reuse is 👌
const dataPagenameOverrides = {
'data-pagename': 'main:p2p:send::funnel',
'data-pagename2': 'main:p2p:send::funnel:node::',
}
function SendMoney(props) {
return (
<NewUserFunnelPage>
<BackLink />
<glamorous.Div display="flex" justifyContent="space-between">
<div>
<PageTitle>{i18n('newUser.sendMoney.title')}</PageTitle>
<PageSubtitle />
</div>
<SendSVG />
</glamorous.Div>
<LinkContainer>
<LinkCard
{...funnelProps.buyLink(props)}
descriptionHTMLKey="newUser.sendMoney.goodsAndServices.description"
{...dataPagenameOverrides}
/>
<LinkCard {...funnelProps.sendLink(props)} {...dataPagenameOverrides} />
<LinkCard {...funnelProps.xbLink(props)} {...dataPagenameOverrides} />
<LinkCard {...funnelProps.giftLink(props)} {...dataPagenameOverrides} />
<Protection>
<div
dangerouslySetInnerHTML={{
__html: i18n('newUser.sendMoney.purchaseProtection'),
}}
/>
</Protection>
</LinkContainer>
</NewUserFunnelPage>
)
}
Resources
- CSS in JS - Vjeux - "The original"
- glamor - Sunil Pai - css in your javascript
- glamorous - PayPal - React component Styling Solved 💄
- jest-glamor-react - Kent C. Dodds - Jest utilities for Glamor and React
- Code Sandbox - the examples from these slides in an interactive code editor in your browser.
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Thank you!
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Styling React Components
By Kent C. Dodds
Styling React Components
The CSS-in-JS movement is strong in the community and we're still figuring things out. But one thing is clear: keeping your UI logic, markup, and styles together to make a single component is a great way to build applications.
- 5,611