90 lines
2.5 KiB
Markdown
90 lines
2.5 KiB
Markdown
---
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title: Use GestureDetector for Animated Press States
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impact: MEDIUM
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impactDescription: UI thread animations, smoother press feedback
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tags: animation, gestures, press, reanimated
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---
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## Use GestureDetector for Animated Press States
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For animated press states (scale, opacity on press), use `GestureDetector` with
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`Gesture.Tap()` and shared values instead of Pressable's
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`onPressIn`/`onPressOut`. Gesture callbacks run on the UI thread as worklets—no
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JS thread round-trip for press animations.
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**Incorrect (Pressable with JS thread callbacks):**
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```tsx
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import { Pressable } from "react-native";
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import Animated, { useSharedValue, useAnimatedStyle, withTiming } from "react-native-reanimated";
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function AnimatedButton({ onPress }: { onPress: () => void }) {
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const scale = useSharedValue(1);
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const animatedStyle = useAnimatedStyle(() => ({
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transform: [{ scale: scale.value }],
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}));
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return (
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<Pressable
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onPress={onPress}
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onPressIn={() => (scale.value = withTiming(0.95))}
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onPressOut={() => (scale.value = withTiming(1))}
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>
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<Animated.View style={animatedStyle}>
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<Text>Press me</Text>
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</Animated.View>
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</Pressable>
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);
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}
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```
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**Correct (GestureDetector with UI thread worklets):**
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```tsx
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import { Gesture, GestureDetector } from "react-native-gesture-handler";
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import Animated, {
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useSharedValue,
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useAnimatedStyle,
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withTiming,
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interpolate,
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runOnJS,
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} from "react-native-reanimated";
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function AnimatedButton({ onPress }: { onPress: () => void }) {
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// Store the press STATE (0 = not pressed, 1 = pressed)
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const pressed = useSharedValue(0);
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const tap = Gesture.Tap()
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.onBegin(() => {
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pressed.set(withTiming(1));
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})
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.onFinalize(() => {
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pressed.set(withTiming(0));
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})
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.onEnd(() => {
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runOnJS(onPress)();
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});
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// Derive visual values from the state
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const animatedStyle = useAnimatedStyle(() => ({
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transform: [{ scale: interpolate(withTiming(pressed.get()), [0, 1], [1, 0.95]) }],
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}));
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return (
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<GestureDetector gesture={tap}>
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<Animated.View style={animatedStyle}>
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<Text>Press me</Text>
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</Animated.View>
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</GestureDetector>
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);
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}
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```
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Store the press **state** (0 or 1), then derive the scale via `interpolate`.
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This keeps the shared value as ground truth. Use `runOnJS` to call JS functions
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from worklets. Use `.set()` and `.get()` for React Compiler compatibility.
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Reference:
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[Gesture Handler Tap Gesture](https://docs.swmansion.com/react-native-gesture-handler/docs/gestures/tap-gesture)
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