探索创新图片交互：React Native Image Pan Zoom

import React from 'react';
import { View, StyleSheet, Image } from 'react-native';
import FastImage from 'react-native-fast-image';
import { PanGestureHandler, State } from 'react-native-gesture-handler';
import Animated, { useAnimatedGestureHandler, useAnimatedStyle, withTiming, runOnJS } from 'react-native-reanimated';
 
export default function ImagePanZoom({ source }) {
  const translateX = useSharedValue(0);
  const translateY = useSharedValue(0);
  const scale = useSharedValue(1);
 
  const panGestureHandler = useAnimatedGestureHandler({
    onStart: (_, ctx) => {
      ctx.offsetX = 0;
      ctx.offsetY = 0;
      ctx.scale = scale.value;
    },
    onActive: (event, ctx) => {
      const { translationX, translationY } = event;
      translateX.value = ctx.scale * translationX + ctx.offsetX;
      translateY.value = ctx.scale * translationY + ctx.offsetY;
    },
    onEnd: (event, ctx) => {
      const { velocityX, velocityY } = event;
      runOnJS(setOffset)(translateX, translateY, velocityX, velocityY, scale);
    }
  });
 
  const imageStyle = useAnimatedStyle(() => ({
    transform: [
      { translateX: translateX.value },
      { translateY: translateY.value },
      { scale: scale.value }
    ]
  }));
 
  return (
    <View style={styles.container}>
      <FastImage style={styles.image} source={source} />
      <Animated.View style={[styles.panContainer, imageStyle]}>
        <PanGestureHandler onGestureEvent={panGestureHandler}>
          <Animated.View style={styles.zoomableImageContainer}>
            <FastImage style={styles.zoomableImage} source={source} />
          </Animated.View>
        </PanGestureHandler>
      </Animated.View>
    </View>
  );
}
 
const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center'
  },
  image: {
    width: '100%',
    aspectRatio: 1,
    resizeMode: 'contain'
  },
  panContainer: {
    ...StyleSheet.absoluteFillObject,
    justifyContent: 'center',
    alignItems: 'center'
  },
  zoomableImageContainer: {
    overflow: 'hidden',
    borderWidth: 3,
    borderColor: 'white'
  },
  zoomableImage: {
    width: '100%',
    aspectRatio: 1,
    resizeMode: 'contain'
  }
});

这个代码示例使用了React Nat