Create XY chart, React-Native - react-native
How can I create basic xy chart in react-native? For example I have data:
chart_data = [
[0,0],[0,1],[1,1],[1,0],[0,0]
]
This is the points of a square. Most of all libraries offer to create line chart, which will create other line-type chart and the result for this points would be - trapeze. Help me, please
You should try MPAndroidChart, there's even a react native wrapper for it.
Use react-native-chart
import React, { StyleSheet, View, Component } from 'react-native';
import Chart from 'react-native-chart';
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: 'center',
alignItems: 'center',
backgroundColor: 'white',
},
chart: {
width: 200,
height: 200,
},
});
const data = [
[0, 1],
[1, 3],
[3, 7],
[4, 9],
];
class SimpleChart extends Component {
render() {
return (
<View style={styles.container}>
<Chart
style={styles.chart}
data={data}
verticalGridStep={5}
type="line"
/>
</View>
);
}
}
Note that MPAndroidChart supports Android only, whereas react-native-chart supports both Android and iOS.
Example charts:
You could try to use Canvas and its methods. There you can draw points lines or shapes...
Related
Why are my React Native View heights inconsistent?
I have the following code:
return (
<>
<View style={styles.dashboardListItemContainer}>
<View style={styles.listItemBorder} />
</View >
</>
)
const styles = StyleSheet.create({
dashboardListItemContainer: {
minHeight: 73,
backgroundColor: COL_DARK_BG,
display: "flex",
flexDirection: "column",
},
listItemBorder: {
minHeight: 0.5,
backgroundColor: 'white',
}
});
Which produces the following result:
My question is, why are the lines inconsistently bright / appear to be different heights?
Also when I change column to row here: flexDirection: "row", the line disappears completely. I can't tell if this is a bug or there are errors in my code?
TIA.
Update:
I cannot solve this problem on any device, and I've tried different methods for determining the height.
borderBottomWidth: StyleSheet.hairlineWidth, looks like this:
You can see in the above picture some lines do not even show up.
borderBottomWidth: StyleSheet.hairlineWidth * 2, looks like this:
And height: 0.5, looks like this on a white background:
The problem is consistent across devices, it is at the edge of an item in a <FlatList>.
Android Emulator has less resolution, try on a real device, sometimes i have the same error, and when I run on a real device it looks good.
We can use flex value.
import React, { Component } from "react";
import { View, FlatList } from "react-native";
import { StyleSheet } from "react-native";
class App extends Component {
render() {
return (
<FlatList
data={[1, 2, 3, 4, 5, 6, 7, 8, 9]}
extraData={[1, 2, 3, 4, 5, 6, 7, 8, 9]}
horizontal={false}
renderItem={({ item, index }) => {
return (
<View style={styles.dashboardListItemContainer}>
<View style={styles.listItemBorder} />
</View>
);
}}
key={({ item, index }) => index}
/>
);
}
}
export default App;
const styles = StyleSheet.create({
dashboardListItemContainer: {
backgroundColor: "red",
display: "flex",
flex: 1,
minHeight: 73,
flexDirection: "column"
},
listItemBorder: {
minHeight: 0.5,
backgroundColor: "yellow"
}
});
swiping on react-native-snap-carousel is not working as expected
I am trying to use react-native-snap-carousel but however, the swiping effect is not working as expected - it is often difficult to swipe left and right, it requires user to swipe harder to move to another picture (as illustrated in the link below). Swiping issue with React Native Snap Carousel I am not able to find any documented soluton but I found one possible prop - swipeThreshold. I try various value, but still the issue persist. Does anyone know the solution to this?
I suggest you to use react-native-image-slider.
it's flexible and easy to use.
https://www.npmjs.com/package/react-native-image-slider
I made a component named slider.js:
import React, { Component } from 'react';
import {
View,
StyleSheet,
Image,
} from 'react-native';
import ImageSlider from 'react-native-image-slider';
export default class Slider extends Component {
render() {
return (
<ImageSlider
loop
autoPlayWithInterval={3000}
images={this.props.dataSource}
customSlide={({ index, item, style, width }) => (
<View key={index} style={[style, styles.customSlide]}>
<Image source={{ uri: item }} style={styles.customImage} />
</View>
)}
/>
);
}
}
const styles = StyleSheet.create({
customImage: {
height: 180,
marginRight: 20,
marginLeft: 20,
borderWidth: 1,
borderRadius: 10,
marginTop: 8,
},
customSlide: {
backgroundColor: '#eee',
},
});
you can add this to your project and use it wherever you need it like this:
import Slider from '../component/slider';
export default class App extends Component {
constructor(props) {
super(props);
this.state = {
images: [
'https://placeimg.com/640/480/nature',
'https://placeimg.com/640/480/tech',
'https://placeimg.com/640/480/animals',
'https://placeimg.com/640/480/tech',
],
}
render() {
return (
<View style={{flex: 1, backgroundColor: '#eee'}}>
<Slider dataSource={this.state.images} />
</View>
);
}
}
TouchableWithoutFeedback never fires touch events
I have the following React-Native code which alerts the user that it was pressed, however it does not respond to anything.
I have tried using different Touchable components but none seem to work, the only one is Button but that's not really what I want, I'm building a slider so a button is not really appropriate for this.
Anyway, here's my code:
import React, {Component} from 'react';
import {View, TouchableWithoutFeedback, Alert, Text} from 'react-native';
import styles from './styles.js';
import LinearGradient from 'react-native-linear-gradient';
export default class BrightnessSlider extends Component {
value: 100;
constructor(...args) {
super(...args);
}
render() {
return (
<LinearGradient start={{x: 0, y: 0}} end={{x: 1, y: 0}} colors={["#222", "#ddd"]} style={styles.brightnessSliderRunnable}>
<View style={styles.brightnessSliderTrack}>
<TouchableWithoutFeedback onPress={() => Alert.alert("Hello World")}>
<View style={styles.brightnessSliderThumb} />
</TouchableWithoutFeedback>
</View>
</LinearGradient>
)
}
}
and ./styles.js
import {StyleSheet} from "react-native";
export default styles = StyleSheet.create({
brightnessSliderRunnable: {
top: 50,
height: 9,
width: width - 20,
left: 10,
backgroundColor: "#555",
opacity: 1,
elevation: 1,
borderWidth: 0
// position: "absolute"
},
brightnessSliderThumb: {
width: 23,
height: 23,
borderColor: "#888",
// opacity: 1,
borderWidth: 2,
backgroundColor: "#ffffff",
position: "absolute",
top: -7,
borderRadius: 5,
elevation: 2
},
brightnessSliderTrack: {
width: "100%",
elevation: 1,
borderWidth: 0
}
});
Thanks for any help
Questioner's original code.
Solution
Added by questioner's solution.
Change position: absolute to position: relative.
Change your style type made by StyleSheet as below.
Your original.
{...styles.colourContainer, opacity: 100 - this.darkness}
Recommend way.
[styles.colourContainer, {opacity: 100 - this.darkness}]
I tested code and it works well when we touch the white square.
Tested on iOS.
Original App.js.
App.js changed by me.
import React, {Component} from 'react';
import {View, Dimensions, Text} from 'react-native';
import BrightnessSlider from '../components/BrightnessSlider';
import styles from '../components/TempStyle.js';
const d = Dimensions.get('window'),
width = d.width,
height = d.height;
export default class BrightnessSliderTest extends Component {
constructor(...args) {
super(...args);
this.darkness = 0;
this.prevColours = ["#ff0000", "#00ff00", "#0000ff"];
}
render() {
// It is not possible just access the style created by StyleSheet.create(). Do not use StyleSheet.create() or change to flatten the StyleSheet object.
const sty = [styles.colourContainer,{ opacity: 100 - this.darkness}];
return (
<View style={styles.container}>
<View style={sty}>
<View style={styles.toolBar}>
<View style={styles.colourPalette}>
{this.prevColours.map((i, a) => <View key={String(a)} style={[styles.colourTile, {backgroundColor: i}]}/>)}
</View>
{/* <Button title={"Save To Palette"} onTap={this.saveToPalette}>Save</Button> */}
</View>
<BrightnessSlider />
</View>
</View>
);
}
}
Why?
I am not sure how you can use your component in other components. But if you do not have container having enough size can show your component, touch area may not work. That is why I use backgroundColor for container sometimes in testing.
Added after testing full code used in question.
It is not possible just access the style through like spread operator created by StyleSheet.create(). Do not use StyleSheet.create() or change to flatten the StyleSheet object.
And Style can be worked differently from platforms(iOS, Android).
get rid of border in Card Component React native element
In the Card Component for react native elements
I'm trying to get rid of the border by setting the border to 0 and borderColor to transparent but there's still a gray outline
<Card
containerStyle={{borderWidth: 0, borderColor: 'transparent', elevation: 0}}
title='HELLO WORLD'
image={require('../images/pic2.jpg')}>
<Text style={{marginBottom: 10}}>
The idea with React Native Elements is more about component structure than actual design.
</Text>
</Card>
Thought it might have been box shadow, but that's not it either
I've got the same issue, and I've found that border appears because the Card element has an elevation default setted to 1
You can override this (for android) :
<Card containerStyle={{elevation:0, backgroundColor:#123}}/>
and in IOS:
const styles = {
container: {
shadowColor: 'rgba(0,0,0, .2)',
shadowOffset: { height: 0, width: 0 },
shadowOpacity: 0, //default is 1
shadowRadius: 0//default is 1
}
}
<Card containerStyle={styles.container} />
Its late but it seems that a lot of people still searching for the Answer.
React Native Elements by default have set both borderWidth and shadow Props, so in order to remove border completely you need to remove both Border and Shadow.
<Card containerStyle={styles.cardCnt}>
<Text>Content</Text>
</Card>
const styles = {
cardCnt: {
borderWidth: 0, // Remove Border
shadowColor: 'rgba(0,0,0, 0.0)', // Remove Shadow for iOS
shadowOffset: { height: 0, width: 0 },
shadowOpacity: 0,
shadowRadius: 0,
elevation: 0 // Remove Shadow for Android
}
};
It looks like react native elements' Card component has a grey border in all of the examples I've seen. I'd suggest building your own card component. Start with something like this and then style it however you want. This one has a bit of shadow which you can turn off by passing it a noShadow prop.
import React from 'react';
import { View, StyleSheet } from 'react-native';
const Card = (props) => {
let shadowStyle = {
shadowColor: COLORS.grey3,
shadowOffset: { width: 0, height: 0 },
shadowOpacity: .5,
shadowRadius: 12,
elevation: 1,
}
if (props.noShadow) {
shadowStyle = {}
}
return (
<View style={[styles.containerStyle, props.style, shadowStyle]}>
{props.children}
</View>
);
};
const styles = StyleSheet.create({
containerStyle: {
padding: 10,
marginHorizontal: 10,
backgroundColor: COLORS.white,
borderRadius: 3,
}
})
export { Card };
Then when you want to use it just
import { Card } from './yourCustomCardFile'
Then in your render method
<Card>
<Text>Any content you want to include on the card</Text>
<Text>More content that you want on the card</Text>
</Card>
set elevation to 0 and borderColor to white like this
<Card containerStyle={{ elevation: 0, borderColor: "white" }}>
set to screen background color Dirty but problem solved.
React-Native: How to add full screen Lottie animation
I am using linear gradient from lottie, the code is working fine with ios but in android its not fitting to full screen, there is some kind of padding between gradient and the view.
On ios its working fine...i tried many ways,
buy including padding to 0 and even margin to -20, but nothing worked...any solution?
import React, { Component } from 'react';
import {
Text,
StyleSheet,
View,
Platform,
Dimensions
} from 'react-native';
import SignInScreen from './src/screens/auth/SignInScreen';
import Animation from 'lottie-react-native';
import anim from './assets/gradient_animated_background.json';
const height = Dimensions.get('window').height + 20;
const width = Dimensions.get('window').width + 20;
export default class App extends Component {
componentDidMount() {
this.animation.play();
}
render() {
return (
<View style={styles.container}>
<Animation
ref={animation => {
this.animation = animation;
}}
style={{
backgroundColor: 'red',
height: '100%',
width: '100%'
}}
loop={true}
source={Platform.OS === 'ios' ? anim : 'gradient_animated_background.json'}
/>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
backgroundColor: 'blue',
flex: 1,
},
welcome: {
fontSize: 20,
textAlign: 'center',
margin: 10,
color: '#ffffff'
}
});
The animation, and when ever i keep changing the width and height..it forcefully tries to maintain the aspect radio...(not sure though)
{"v":"4.6.10","fr":15,"ip":0,"op":155,"w":1080,"h":1920,"nm":"background","ddd":0,"assets":[],"layers":[{"ddd":0,"ind":1,"ty":4,"nm":"Shape Layer 1","ks":{"o":{"a":0,"k":100},"r":{"a":0,"k":0},"p":{"a":0,"k":[540,960,0]},"a":{"a":0,"k":[0,0,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"shapes":[{"ty":"gr","it":[{"ty":"rc","d":1,"s":{"a":0,"k":[1160,880]},"p":{"a":0,"k":[0,0]},"r":{"a":0,"k":0},"nm":"Rectangle Path 1","mn":"ADBE Vector Shape - Rect"},{"ty":"st","c":{"a":0,"k":[0.9960784,0.7843137,0.145098,1]},"o":{"a":0,"k":100},"w":{"a":0,"k":6},"lc":1,"lj":1,"ml":4,"nm":"Stroke 1","mn":"ADBE Vector Graphic - Stroke"},{"ty":"gf","o":{"a":0,"k":100},"r":1,"g":{"p":3,"k":{"a":1,"k":[{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":0,"s":[0,0.511,0.89,0.283,0.5,0.334,0.873,0.583,1,0.156,0.857,0.882],"e":[0,0.726,0.283,0.89,0.5,0.441,0.356,0.886,1,0.156,0.429,0.882]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":31,"s":[0,0.726,0.283,0.89,0.5,0.441,0.356,0.886,1,0.156,0.429,0.882],"e":[0,0.89,0.283,0.283,0.5,0.886,0.553,0.219,1,0.882,0.823,0.156]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":61,"s":[0,0.89,0.283,0.283,0.5,0.886,0.553,0.219,1,0.882,0.823,0.156],"e":[0,0,0.312,0.737,0.5,0.078,0.597,0.754,1,0.156,0.882,0.771]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":91,"s":[0,0,0.312,0.737,0.5,0.078,0.597,0.754,1,0.156,0.882,0.771],"e":[0,0.51,0.89,0.282,0.5,0.333,0.873,0.582,1,0.157,0.855,0.882]},{"t":120}]}},"s":{"a":1,"k":[{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":0,"s":[-430.769,-404.573],"e":[23.726,-364.48],"to":[75.7491683959961,6.68213844299316],"ti":[-123.915840148926,-8.51547145843506]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":31,"s":[23.726,-364.48],"e":[312.726,-353.48],"to":[123.915840148926,8.51547145843506],"ti":[-1.00208830833435,-1.83333337306976]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":61,"s":[312.726,-353.48],"e":[29.739,-353.48],"to":[1.00208830833435,1.83333337306976],"ti":[120.055290222168,0.60746711492538]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":91,"s":[29.739,-353.48],"e":[-407.606,-357.125],"to":[-120.055290222168,-0.60746711492538],"ti":[72.8907089233398,0.60746711492538]},{"t":120}]},"e":{"a":1,"k":[{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":0,"s":[374.412,342.611],"e":[22.822,357.191],"to":[-58.5984153747559,2.42986845970154],"ti":[132.520950317383,-7.89707231521606]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":31,"s":[22.822,357.191],"e":[-420.714,389.994],"to":[-132.520950317383,7.89707231521606],"ti":[-4.68509674072266,-7.89707231521606]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":61,"s":[-420.714,389.994],"e":[50.932,404.573],"to":[4.68509674072266,7.89707231521606],"ti":[-132.918350219727,4.25226974487305]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":91,"s":[50.932,404.573],"e":[376.797,364.48],"to":[132.918350219727,-4.25226974487305],"ti":[-54.3107261657715,6.68213844299316]},{"t":120}]},"t":1,"nm":"Gradient Fill 1","mn":"ADBE Vector Graphic - G-Fill"},{"ty":"tr","p":{"a":0,"k":[0,0],"ix":2},"a":{"a":0,"k":[0,0],"ix":1},"s":{"a":0,"k":[93.29,219.491],"ix":3},"r":{"a":0,"k":0,"ix":6},"o":{"a":0,"k":100,"ix":7},"sk":{"a":0,"k":0,"ix":4},"sa":{"a":0,"k":0,"ix":5},"nm":"Transform"}],"nm":"Rectangle 1","np":3,"cix":2,"ix":1,"mn":"ADBE Vector Group"}],"ip":0,"op":155,"st":0,"bm":0,"sr":1},{"ddd":0,"ind":2,"ty":1,"nm":"Deep Red Solid 1","ks":{"o":{"a":0,"k":100},"r":{"a":0,"k":0},"p":{"a":0,"k":[540,960,0]},"a":{"a":0,"k":[540,960,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"sw":1080,"sh":1920,"sc":"#be2a2a","ip":0,"op":155,"st":0,"bm":0,"sr":1}]}
What you are missing is the resizeMode, which is not specified on the documentation page, but if you look at the source you'll find it.
Here's something that works if you don't care to lose a few pixels:
import React, { Component } from 'react';
import {
StyleSheet,
View,
Dimensions
} from 'react-native';
import LottieView from 'lottie-react-native';
import { anim } from './assets/animation.json';
const { height, width } = Dimensions.get('window')
export default class App extends Component {
componentDidMount() {
this.animation.play();
}
render() {
return (
<View style={styles.container}>
<LottieView
ref={animation => {
this.animation = animation;
}}
style={{
width: width + 10,
height: height,
marginLeft: - 5
}}
resizeMode='cover'
loop={true}
source={anim}
/>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
backgroundColor: 'blue',
flex: 1,
},
});
Notice that I've exported the asset a bit differently since I tried this on https://snack.expo.io and for some reason they don't like JSON files 😁, so now the assets look something
/assets/animation.json.js
export const anim = {"v":"4.6.10","fr":15,"ip":0,"op":155,"w":1080,"h":1920,"nm":"background","ddd":0,"assets":[],"layers":[{"ddd":0,"ind":1,"ty":4,"nm":"Shape Layer 1","ks":{"o":{"a":0,"k":100},"r":{"a":0,"k":0},"p":{"a":0,"k":[540,960,0]},"a":{"a":0,"k":[0,0,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"shapes":[{"ty":"gr","it":[{"ty":"rc","d":1,"s":{"a":0,"k":[1160,880]},"p":{"a":0,"k":[0,0]},"r":{"a":0,"k":0},"nm":"Rectangle Path 1","mn":"ADBE Vector Shape - Rect"},{"ty":"st","c":{"a":0,"k":[0.9960784,0.7843137,0.145098,1]},"o":{"a":0,"k":100},"w":{"a":0,"k":6},"lc":1,"lj":1,"ml":4,"nm":"Stroke 1","mn":"ADBE Vector Graphic - Stroke"},{"ty":"gf","o":{"a":0,"k":100},"r":1,"g":{"p":3,"k":{"a":1,"k":[{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":0,"s":[0,0.511,0.89,0.283,0.5,0.334,0.873,0.583,1,0.156,0.857,0.882],"e":[0,0.726,0.283,0.89,0.5,0.441,0.356,0.886,1,0.156,0.429,0.882]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":31,"s":[0,0.726,0.283,0.89,0.5,0.441,0.356,0.886,1,0.156,0.429,0.882],"e":[0,0.89,0.283,0.283,0.5,0.886,0.553,0.219,1,0.882,0.823,0.156]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":61,"s":[0,0.89,0.283,0.283,0.5,0.886,0.553,0.219,1,0.882,0.823,0.156],"e":[0,0,0.312,0.737,0.5,0.078,0.597,0.754,1,0.156,0.882,0.771]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":91,"s":[0,0,0.312,0.737,0.5,0.078,0.597,0.754,1,0.156,0.882,0.771],"e":[0,0.51,0.89,0.282,0.5,0.333,0.873,0.582,1,0.157,0.855,0.882]},{"t":120}]}},"s":{"a":1,"k":[{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":0,"s":[-430.769,-404.573],"e":[23.726,-364.48],"to":[75.7491683959961,6.68213844299316],"ti":[-123.915840148926,-8.51547145843506]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":31,"s":[23.726,-364.48],"e":[312.726,-353.48],"to":[123.915840148926,8.51547145843506],"ti":[-1.00208830833435,-1.83333337306976]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":61,"s":[312.726,-353.48],"e":[29.739,-353.48],"to":[1.00208830833435,1.83333337306976],"ti":[120.055290222168,0.60746711492538]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":91,"s":[29.739,-353.48],"e":[-407.606,-357.125],"to":[-120.055290222168,-0.60746711492538],"ti":[72.8907089233398,0.60746711492538]},{"t":120}]},"e":{"a":1,"k":[{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":0,"s":[374.412,342.611],"e":[22.822,357.191],"to":[-58.5984153747559,2.42986845970154],"ti":[132.520950317383,-7.89707231521606]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":31,"s":[22.822,357.191],"e":[-420.714,389.994],"to":[-132.520950317383,7.89707231521606],"ti":[-4.68509674072266,-7.89707231521606]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":61,"s":[-420.714,389.994],"e":[50.932,404.573],"to":[4.68509674072266,7.89707231521606],"ti":[-132.918350219727,4.25226974487305]},{"i":{"x":0.833,"y":0.833},"o":{"x":0.167,"y":0.167},"n":"0p833_0p833_0p167_0p167","t":91,"s":[50.932,404.573],"e":[376.797,364.48],"to":[132.918350219727,-4.25226974487305],"ti":[-54.3107261657715,6.68213844299316]},{"t":120}]},"t":1,"nm":"Gradient Fill 1","mn":"ADBE Vector Graphic - G-Fill"},{"ty":"tr","p":{"a":0,"k":[0,0],"ix":2},"a":{"a":0,"k":[0,0],"ix":1},"s":{"a":0,"k":[93.29,219.491],"ix":3},"r":{"a":0,"k":0,"ix":6},"o":{"a":0,"k":100,"ix":7},"sk":{"a":0,"k":0,"ix":4},"sa":{"a":0,"k":0,"ix":5},"nm":"Transform"}],"nm":"Rectangle 1","np":3,"cix":2,"ix":1,"mn":"ADBE Vector Group"}],"ip":0,"op":155,"st":0,"bm":0,"sr":1},{"ddd":0,"ind":2,"ty":1,"nm":"Deep Red Solid 1","ks":{"o":{"a":0,"k":100},"r":{"a":0,"k":0},"p":{"a":0,"k":[540,960,0]},"a":{"a":0,"k":[540,960,0]},"s":{"a":0,"k":[100,100,100]}},"ao":0,"sw":1080,"sh":1920,"sc":"#be2a2a","ip":0,"op":155,"st":0,"bm":0,"sr":1}]}
So the first answer raised an important point (adding resizeMode="cover").
But that's not enough, If you test across several screens sizes, you might still find unwanted margins and spaces. I had this issue too,
Here's the simple solution:
Get the dimensions of the lottie file (e.g 300 X 600)
Set width only, then use aspectRatio to determine the height. (must)
Set flexGrow = 1 (must)
e.g
<LottieView
style={{
width: 300,
aspectRatio: 300 / 600,
flexGrow: 1,
alignSelf: 'center',
}}
resizeMode="cover"
ref={animation=> { this.animation = animation; }}
source={require ('./assets/animation.json')}
autoPlay={false}
loop={false}
/>
I guess the problem arises because you cant use width and height at the same time in the styling of the Lottie view.
So an easy workaround is to use the width and aspectRatio
Good luck!