Maintain aspect ratio of image with full width in React Native
I like bdv's approach and I use this kind of images almost everywhere in my app. That's why I created an own component which is using onLayout
to also support device rotation.
import resolveAssetSource from "resolveAssetSource";
import React, { useCallback, useState } from "react";
import { Image, View } from "react-native";
export default function FullWidthImage(props) {
const [width, setWidth] = useState(0);
const [height, setHeight] = useState(0);
const onLayout = useCallback((event) => {
const containerWidth = event.nativeEvent.layout.width;
if (props.ratio) {
setWidth(containerWidth);
setHeight(containerWidth * props.ratio);
} else if (typeof props.source === "number") {
const source = resolveAssetSource(props.source);
setWidth(containerWidth);
setHeight(containerWidth * source.height / source.width);
} else if (typeof props.source === "object") {
Image.getSize(props.source.uri, (w, h) => {
setWidth(containerWidth);
setHeight(containerWidth * h / w);
});
}
}, [props.ratio, props.source]);
return (
<View onLayout={onLayout}>
<Image
source={props.source}
style={{ width, height }} />
</View>
);
}
You can use it like this:
<FullWidthImage source={{ uri: "http://example.com/image.jpg" }} />
<FullWidthImage source={require("./images/image.jpg")} />
Or if you know the ratio like this:
<FullWidthImage source={{ uri: "http://example.com/image.jpg"}} ratio={0.5} />
<FullWidthImage source={require("./images/image.jpg")} ratio={0.5} />
<Image
source={require('../../assets/img/headers/image-1.jpg')}
style={styles.responsiveImage}
/>
const styles = StyleSheet.create({
responsiveImage: {
width: '100%',
// Without height undefined it won't work
height: undefined,
// figure out your image aspect ratio
aspectRatio: 135 / 76,
},
});
Use style={{ aspectRatio: 3/2 }}
for a horizontal image with width to height ratio of 3:2.
Docs: https://reactnative.dev/docs/layout-props#aspectratio
(Available in RN 0.40+)