Rocket.Chat.ReactNative/app/containers/ImageViewer/ImageViewer.tsx

132 lines
3.7 KiB
TypeScript

import React, { useState } from 'react';
import { LayoutChangeEvent, StyleSheet, StyleProp, ViewStyle, ImageStyle, View } from 'react-native';
import { Gesture, GestureDetector } from 'react-native-gesture-handler';
import Animated, { withTiming, useSharedValue, useAnimatedStyle, withSpring } from 'react-native-reanimated';
import { useTheme } from '../../theme';
import { ImageComponent } from './ImageComponent';
interface ImageViewerProps {
style?: StyleProp<ImageStyle>;
containerStyle?: StyleProp<ViewStyle>;
imageContainerStyle?: StyleProp<ViewStyle>;
uri: string;
imageComponentType?: string;
width: number;
height: number;
onLoadEnd?: () => void;
}
const styles = StyleSheet.create({
flex: {
flex: 1
},
image: {
flex: 1
}
});
export const ImageViewer = ({ uri = '', imageComponentType, width, height, ...props }: ImageViewerProps): React.ReactElement => {
const [centerX, setCenterX] = useState(0);
const [centerY, setCenterY] = useState(0);
const onLayout = ({
nativeEvent: {
layout: { x, y, width, height }
}
}: LayoutChangeEvent) => {
setCenterX(x + width / 2);
setCenterY(y + height / 2);
};
const translationX = useSharedValue<number>(0);
const translationY = useSharedValue<number>(0);
const offsetX = useSharedValue<number>(0);
const offsetY = useSharedValue<number>(0);
const scale = useSharedValue<number>(1);
const scaleOffset = useSharedValue<number>(1);
const style = useAnimatedStyle(() => ({
transform: [{ translateX: translationX.value }, { translateY: translationY.value }, { scale: scale.value }]
}));
const resetScaleAnimation = () => {
'worklet';
scaleOffset.value = 1;
offsetX.value = 0;
offsetY.value = 0;
scale.value = withSpring(1);
translationX.value = withSpring(0, { overshootClamping: true });
translationY.value = withSpring(0, { overshootClamping: true });
};
const clamp = (value: number, min: number, max: number) => {
'worklet';
return Math.max(Math.min(value, max), min);
};
const pinchGesture = Gesture.Pinch()
.onUpdate(event => {
scale.value = clamp(scaleOffset.value * (event.scale > 0 ? event.scale : 1), 1, 4);
})
.onEnd(() => {
scaleOffset.value = scale.value > 0 ? scale.value : 1;
});
const panGesture = Gesture.Pan()
.maxPointers(2)
.onStart(() => {
translationX.value = offsetX.value;
translationY.value = offsetY.value;
})
.onUpdate(event => {
const scaleFactor = scale.value - 1;
translationX.value = clamp(event.translationX + offsetX.value, -scaleFactor * centerX, scaleFactor * centerX);
translationY.value = clamp(event.translationY + offsetY.value, -scaleFactor * centerY, scaleFactor * centerY);
})
.onEnd(() => {
offsetX.value = translationX.value;
offsetY.value = translationY.value;
if (scale.value === 1) resetScaleAnimation();
});
const doubleTapGesture = Gesture.Tap()
.numberOfTaps(2)
.maxDelay(120)
.maxDistance(70)
.onEnd(event => {
if (scaleOffset.value > 1) resetScaleAnimation();
else {
scale.value = withTiming(2, { duration: 200 });
translationX.value = withTiming(centerX - event.x, { duration: 200 });
offsetX.value = centerX - event.x;
scaleOffset.value = 2;
}
});
const gesture = Gesture.Simultaneous(pinchGesture, panGesture, doubleTapGesture);
const Component = ImageComponent(imageComponentType);
const { colors } = useTheme();
return (
<View style={[styles.flex, { width, height, backgroundColor: colors.previewBackground }]}>
<GestureDetector gesture={gesture}>
<Animated.View onLayout={onLayout} style={[styles.flex, style]}>
<Component
// @ts-ignore
style={styles.image}
resizeMode='contain'
source={{ uri }}
{...props}
/>
</Animated.View>
</GestureDetector>
</View>
);
};