72 lines
1.4 KiB
Markdown
72 lines
1.4 KiB
Markdown
---
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title: Load fonts natively at build time
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impact: LOW
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impactDescription: fonts available at launch, no async loading
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tags: fonts, expo, performance, config-plugin
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---
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## Use Expo Config Plugin for Font Loading
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Use the `expo-font` config plugin to embed fonts at build time instead of
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`useFonts` or `Font.loadAsync`. Embedded fonts are more efficient.
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**Incorrect (async font loading):**
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```tsx
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import { useFonts } from "expo-font";
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import { Text, View } from "react-native";
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function App() {
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const [fontsLoaded] = useFonts({
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"Geist-Bold": require("./assets/fonts/Geist-Bold.otf"),
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});
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if (!fontsLoaded) {
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return null;
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}
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return (
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<View>
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<Text style={{ fontFamily: "Geist-Bold" }}>Hello</Text>
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</View>
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);
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}
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```
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**Correct (config plugin, fonts embedded at build):**
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```json
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// app.json
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{
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"expo": {
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"plugins": [
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[
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"expo-font",
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{
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"fonts": ["./assets/fonts/Geist-Bold.otf"]
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}
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]
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]
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}
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}
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```
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```tsx
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import { Text, View } from "react-native";
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function App() {
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// No loading state needed—font is already available
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return (
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<View>
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<Text style={{ fontFamily: "Geist-Bold" }}>Hello</Text>
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</View>
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);
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}
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```
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After adding fonts to the config plugin, run `npx expo prebuild` and rebuild the
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native app.
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Reference:
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[Expo Font Documentation](https://docs.expo.dev/versions/latest/sdk/font/)
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