use-dom
expo
Use Expo DOM components to run web code in a webview on native and as-is on web. Migrate web code to native incrementally.
bunx add-skill expo/skills -s use-domLoadingβ¦
expo
Use Expo DOM components to run web code in a webview on native and as-is on web. Migrate web code to native incrementally.
bunx add-skill expo/skills -s use-domLoadingβ¦
DOM components allow web code to run verbatim in a webview on native platforms while rendering as-is on web. This enables using web-only libraries like recharts, react-syntax-highlighter, or any React web library in your Expo app without modification.
Use DOM components when you need:
Avoid DOM components when:
_layout files cannot be DOM componentsCreate a new file with the 'use dom'; directive at the top:
// components/WebChart.tsx
"use dom";
export default function WebChart({
data,
}: {
data: number[];
dom: import("expo/dom").DOMProps;
}) {
return (
<div style={{ padding: 20 }}>
<h2>Chart Data</h2>
<ul>
{data.map((value, i) => (
<li key={i}>{value}</li>
))}
</ul>
</div>
);
}
'use dom'; directive at the top of the filedom PropEvery DOM component receives a special dom prop for webview configuration. Always type it in your props:
"use dom";
interface Props {
content: string;
dom: import("expo/dom").DOMProps;
}
export default function MyComponent({ content }: Props) {
return <div>{content}</div>;
}
dom Prop Options// Disable body scrolling
<DOMComponent dom={{ scrollEnabled: false }} />
// Flow under the notch (disable safe area insets)
<DOMComponent dom={{ contentInsetAdjustmentBehavior: "never" }} />
// Control size manually
<DOMComponent dom={{ style: { width: 300, height: 400 } }} />
// Combine options
<DOMComponent
dom={{
scrollEnabled: false,
contentInsetAdjustmentBehavior: "never",
style: { width: '100%', height: 500 }
}}
/>
Pass async functions as props to expose native functionality to the DOM component:
// app/index.tsx (native)
import { Alert } from "react-native";
import DOMComponent from "@/components/dom-component";
export default function Screen() {
return (
<DOMComponent
showAlert={async (message: string) => {
Alert.alert("From Web", message);
}}
saveData={async (data: { name: string; value: number }) => {
// Save to native storage, database, etc.
console.log("Saving:", data);
return { success: true };
}}
/>
);
}
// components/dom-component.tsx
"use dom";
interface Props {
showAlert: (message: string) => Promise<void>;
saveData: (data: {
name: string;
value: number;
}) => Promise<{ success: boolean }>;
dom?: import("expo/dom").DOMProps;
}
export default function DOMComponent({ showAlert, saveData }: Props) {
const handleClick = async () => {
await showAlert("Hello from the webview!");
const result = await saveData({ name: "test", value: 42 });
console.log("Save result:", result);
};
return <button onClick={handleClick}>Trigger Native Action</button>;
}
DOM components can use any web library:
// components/syntax-highlight.tsx
"use dom";
import SyntaxHighlighter from "react-syntax-highlighter";
import { docco } from "react-syntax-highlighter/dist/esm/styles/hljs";
interface Props {
code: string;
language: string;
dom?: import("expo/dom").DOMProps;
}
export default function SyntaxHighlight({ code, language }: Props) {
return (
<SyntaxHighlighter language={language} style={docco}>
{code}
</SyntaxHighlighter>
);
}
// components/chart.tsx
"use dom";
import {
LineChart,
Line,
XAxis,
YAxis,
CartesianGrid,
Tooltip,
} from "recharts";
interface Props {
data: Array<{ name: string; value: number }>;
dom: import("expo/dom").DOMProps;
}
export default function Chart({ data }: Props) {
return (
<LineChart width={400} height={300} data={data}>
<CartesianGrid strokeDasharray="3 3" />
<XAxis dataKey="name" />
<YAxis />
<Tooltip />
<Line type="monotone" dataKey="value" stroke="#8884d8" />
</LineChart>
);
}
CSS imports must be in the DOM component file since they run in isolated context:
// components/styled-component.tsx
"use dom";
import "@/styles.css"; // CSS file in same directory
export default function StyledComponent({
dom,
}: {
dom: import("expo/dom").DOMProps;
}) {
return (
<div className="container">
<h1 className="title">Styled Content</h1>
</div>
);
}
Or use inline styles / CSS-in-JS:
"use dom";
const styles = {
container: {
padding: 20,
backgroundColor: "#f0f0f0",
},
title: {
fontSize: 24,
color: "#333",
},
};
export default function StyledComponent({
dom,
}: {
dom: import("expo/dom").DOMProps;
}) {
return (
<div style={styles.container}>
<h1 style={styles.title}>Styled Content</h1>
</div>
);
}
The expo-router <Link /> component and router API work inside DOM components:
"use dom";
import { Link, useRouter } from "expo-router";
export default function Navigation({
dom,
}: {
dom: import("expo/dom").DOMProps;
}) {
const router = useRouter();
return (
<nav>
<Link href="/about">About</Link>
<button onClick={() => router.push("/settings")}>Settings</button>
</nav>
);
}
These hooks don't work directly in DOM components because they need synchronous access to native routing state:
useLocalSearchParams()useGlobalSearchParams()usePathname()useSegments()useRootNavigation()useRootNavigationState()Solution: Read these values in the native parent and pass as props:
// app/[id].tsx (native)
import { useLocalSearchParams, usePathname } from "expo-router";
import DOMComponent from "@/components/dom-component";
export default function Screen() {
const { id } = useLocalSearchParams();
const pathname = usePathname();
return <DOMComponent id={id as string} pathname={pathname} />;
}
// components/dom-component.tsx
"use dom";
interface Props {
id: string;
pathname: string;
dom?: import("expo/dom").DOMProps;
}
export default function DOMComponent({ id, pathname }: Props) {
return (
<div>
<p>Current ID: {id}</p>
<p>Current Path: {pathname}</p>
</div>
);
}
Check if code is running in a DOM component:
"use dom";
import { IS_DOM } from "expo/dom";
export default function Component({
dom,
}: {
dom?: import("expo/dom").DOMProps;
}) {
return <div>{IS_DOM ? "Running in DOM component" : "Running natively"}</div>;
}
Prefer requiring assets instead of using the public directory:
"use dom";
// Good - bundled with the component
const logo = require("../assets/logo.png");
export default function Component({
dom,
}: {
dom: import("expo/dom").DOMProps;
}) {
return <img src={logo} alt="Logo" />;
}
Import and use DOM components like regular components:
// app/index.tsx
import { View, Text } from "react-native";
import WebChart from "@/components/web-chart";
import CodeBlock from "@/components/code-block";
export default function HomeScreen() {
return (
<View style={{ flex: 1 }}>
<Text>Native content above</Text>
<WebChart data={[10, 20, 30, 40, 50]} dom={{ style: { height: 300 } }} />
<CodeBlock
code="const x = 1;"
language="javascript"
dom={{ scrollEnabled: true }}
/>
<Text>Native content below</Text>
</View>
);
}
| Platform | Behavior |
|---|---|
| iOS | Rendered in WKWebView |
| Android | Rendered in WebView |
| Web | Rendered as-is (no webview wrapper) |
On web, the dom prop is ignored since no webview is needed.
Use when you need to run Flow type checking, or when seeing Flow type errors in React code.
Use when you want to validate changes before committing, or when you need to check all React contribution requirements.
Use when feature flag tests fail, flags need updating, understanding @gate pragmas, debugging channel-specific test failures, or adding new flags to React.
Use when you need to check feature flag states, compare channels, or debug why a feature behaves differently across release channels.