@alloc/restyle
v3.0.1
Published
A system for building constraint-based UI components
Readme
@alloc/restyle
@alloc/restyle is a fork of @shopify/restyle for building consistent, themeable, type-safe UI in React Native + TypeScript.
It differs from the original in three key ways:
- Optional theme properties — All properties of
createTheme(colors,spacing, etc.) are optional. - Arbitrary values allowed — You can pass raw values (colors, spacing, etc.) directly to JSX props without declaring them in the theme.
- TypeScript ref typing — Forward refs are properly typed, allowing you to specify the ref type for full type safety with any base component.
1. Core Concepts
ThemeProvider
Wrap your app in a ThemeProvider to supply a theme:
import {ThemeProvider} from '@alloc/restyle';
import theme from './theme';
export default function App() {
return (
<ThemeProvider theme={theme}>
<MyApp />
</ThemeProvider>
);
}Creating Components
createBox<Theme>()→ Base layout component with forward ref supportcreateText<Theme>()→ Text component with typography support and forward ref support
import {createBox, createText} from '@alloc/restyle';
import {Theme} from './theme';
const Box = createBox<Theme>();
const Text = createText<Theme>();
// Forward refs are automatically supported
const MyComponent = () => {
const boxRef = useRef();
const textRef = useRef();
return (
<>
<Box ref={boxRef} padding="m" />
<Text ref={textRef} variant="body">
Hello
</Text>
</>
);
};You can also wrap third-party components and specify their ref type:
import {createBox} from '@alloc/restyle';
import {FlashList} from '@shopify/flash-list';
import type {FlashListRef} from '@shopify/flash-list';
// Wrap FlashList with restyle props and proper ref typing
const StyledFlashList = createBox<
Theme,
React.ComponentProps<typeof FlashList<any>>,
FlashListRef<any>
>(FlashList);
const MyComponent = () => {
const flashListRef = useRef<FlashListRef<any>>();
return (
<StyledFlashList
ref={flashListRef}
padding="m"
backgroundColor="white"
data={data}
renderItem={renderItem}
estimatedItemSize={50}
/>
);
};Defining a Theme
import {createTheme} from '@alloc/restyle';
const theme = createTheme({
colors: {
mainBackground: '#fff',
primary: '#007AFF',
},
spacing: {
s: 8,
m: 16,
l: 24,
},
textVariants: {
header: {fontSize: 32, fontWeight: 'bold'},
body: {fontSize: 16, lineHeight: 24},
},
});
export type Theme = typeof theme;
export default theme;✅ With @alloc/restyle, any of these keys can be omitted, and you may still pass values directly:
<Box padding={12} backgroundColor="#f00" />2. Styling with Props
Restyle Props
Every Restyle component accepts props like:
backgroundColor="primary"padding="m"flexDirection="row"
These props map directly to style objects and can be responsive.
Responsive Values
Use the breakpoints key in your theme:
const theme = createTheme({
breakpoints: {phone: 0, tablet: 768},
});
// Usage
return <Box flexDirection={{phone: 'column', tablet: 'row'}} />;Or read responsive values inside components:
import {useResponsiveProp} from '@alloc/restyle';
const color = useResponsiveProp({phone: 'red', tablet: 'blue'});3. Variants
Variants let you define reusable style presets in your theme.
const theme = createTheme({
cardVariants: {
regular: {padding: 'm', backgroundColor: 'white'},
elevated: {padding: 'm', shadowOpacity: 0.2, elevation: 4},
},
});
import {
createVariant,
createRestyleComponent,
VariantProps,
} from '@alloc/restyle';
type Theme = typeof theme;
const Card = createRestyleComponent<
VariantProps<Theme, 'cardVariants'> & React.ComponentProps<typeof Box>,
Theme
>([createVariant({themeKey: 'cardVariants'})], Box);
// Usage
return <Card variant="elevated" />;4. Hooks
useTheme
Access the current theme:
import {useTheme} from '@alloc/restyle';
const MyComponent = () => {
const theme = useTheme<Theme>();
return <Box backgroundColor={theme.colors.primary} />;
};useRestyle
Compose custom components with multiple Restyle functions:
import {useRestyle, spacing, border, backgroundColor} from '@alloc/restyle';
const restyleFns = [spacing, border, backgroundColor];
const Button = props => {
const restyled = useRestyle(restyleFns, props);
return <TouchableOpacity {...restyled} />;
};5. Predefined Functions & Components
Built-in Restyle Functions
- Colors:
backgroundColor,color,shadowColor,textShadowColor - Spacing:
margin,padding,gap - Layout:
width,height,flex,alignItems,justifyContent - Border:
borderWidth,borderColor,borderRadius - Typography:
fontSize,lineHeight,fontWeight - Shadows:
shadowOpacity,elevation - Position:
position,top,left,zIndex - …and more
Predefined Components
- Box → includes
backgroundColor,spacing,border,shadow,layout, etc. - Text → includes
color,typography,spacing,layout, and supportstextVariants
Both components automatically forward refs to their underlying React Native components (View and Text respectively), giving you access to native methods like measure(), focus(), etc.
6. Advanced Features
Custom Restyle Functions
Custom restyle functions allow you to create reusable style transformations:
import {createRestyleFunction, createRestyleComponent} from '@alloc/restyle';
import {ViewProps, View} from 'react-native';
const transparency = createRestyleFunction({
property: 'transparency',
styleProperty: 'opacity',
transform: ({value}) => 1 - value,
});
type TransparencyProps = {
transparency?: number;
};
const TransparentView = createRestyleComponent<
TransparencyProps & ViewProps,
Theme
>([transparency]);
// Usage
return <TransparentView transparency={0.3} />;Overriding Styles
Every Restyle component still accepts a style prop for last-layer overrides:
<Box padding="m" style={{backgroundColor: '#f0f'}} />Dark Mode
Swap themes dynamically:
<ThemeProvider theme={darkMode ? darkTheme : lightTheme}>
<App />
</ThemeProvider>