How to prevent scrolling multiple elements in React-Native ScrollView? - react-native

I'm attempting to create a horizontal ScrollView that snaps to an interval. I only want it to scroll one item/element at a time, no matter how much force is applied to their swipe gesture.
I've tried using the available props on ScrollView, and it does what I want nearly perfectly, other than the fact that when more force or longer swipe is applied, multiple elements get scrolled through.
I made a snack on expo here: https://snack.expo.io/BkKzYHpbE
import React, { Component } from 'react';
import { View, StyleSheet, ScrollView, Dimensions } from 'react-native';
const { width } = Dimensions.get('window');
export default class App extends Component {
render() {
return (
<ScrollView
style={styles.container}
horizontal= {true}
decelerationRate={0}
snapToInterval={width - 60}
snapToAlignment={"center"}
contentInset={{
top: 0,
left: 30,
bottom: 0,
right: 30,
}}>
<View style={styles.view} />
<View style={styles.view2} />
<View style={styles.view} />
<View style={styles.view2} />
<View style={styles.view} />
</ScrollView>
);
}
}
const styles = StyleSheet.create({
container: {},
view: {
marginTop: 100,
backgroundColor: 'blue',
width: width - 80,
margin: 10,
height: 200,
borderRadius: 10,
},
view2: {
marginTop: 100,
backgroundColor: 'red',
width: width - 80,
margin: 10,
height: 200,
borderRadius: 10,
},
});
You can see a gentle, short swipe will scroll one element as expected. But a longer, more forceful swipe causes elements to be skipped, which is not what I'd expect.

Use 'pagingEnabled' prop of scrollView. That will solve your problem.
Also remove snapToAlignment and snapToInterval props

Related

ImageBackground is not taking full height of View in react native

I am using ImageBackground in my react native app, but it not covering full height of the View
You can see that there is red space which is not covered by my image.
Below is my code:
<View
style={styles.subDomainItem}>
<ImageBackground
resizeMode={'cover'}
source={ImageConfig.script_default_cloud}
style={{
width: '100%',
height: (dimensions.width - 20) / 2,
backgroundColor: 'red',
flex: 1,
justifyContent: 'center',
}}></ImageBackground>
</View>
subDomainItem: {
maxWidth: '94%',
width: '94%',
marginHorizontal: '3%',
marginVertical: 10,
overflow: 'hidden',
borderRadius: 10,
flex: 1,
elevation: 8,
},
I want my image to cover all the red spaces at top and bottom, but I don't know what I am doing wrong.
Try this. is wroking fine
import React from 'react'
import { View, ImageBackground,Text, Dimensions } from 'react-native'
const Backimage = () => {
return(
<ImageBackground
style={{width:Dimensions.get("screen").width, height:Dimensions.get("screen").height}}
source={require("./src/assets/water.png")} resizeMethod="resize">
</ImageBackground>
)
}
export default Backimage
I think you should give your subDomainItem view an explicit height when styling it. You gave it a width of 94% but you havenā€˜t specified a height.
ImageBackground should then work properly by giving it a height of 100% if the parent component (subDomainItem in this case) has an explicit height.
You don't want to give a height and width for ImageBackground if you want to cover all space of parent View you just need give flex: 1 or height and width to 100% for ImageBackground.
import {
View,
Text,
ImageBackground,
Dimensions,
StyleSheet,
} from 'react-native';
const WIDTH = Dimensions.get('screen').width;
const HEIGHT = Dimensions.get('screen').height;
const MainPage = () => {
return (
<View style={styles.subDomainItem}>
<ImageBackground
resizeMode="contain"
source={ImageConfig.script_default_cloud}
style={styles.bgImageStyle}
>
<Text>Sample</Text>
</ImageBackground>
</View>
);
};
const styles = StyleSheet.create({
subDomainItem: {
width: WIDTH,
height: HEIGHT,
alignItems: 'center',
},
bgImageStyle: {
justifyContent: 'center',
resizeMode: 'contain',
width: WIDTH,
height: HEIGHT,
}
})

react-native-image-slider-box with dotStyle above image Slider not working

In this example i have used react-native-image-slider here i want to show image pagination dots at left side bottom image slider box how to do like that.
SliderBoxExample.js
import React, { Component } from 'react';
import {Image, Text, View, TouchableOpacity, StyleSheet } from 'react-native';
import { SliderBox } from "react-native-image-slider-box";
export default class SliderBoxExample extends Component {
constructor(props) {
super(props);
this.state = {
images: [
require('./../assets/images/cat.jpg'),
require('./../assets/images/dao.jpg'),
require('./../assets/images/monkey.jpg'),
]
};
}
render() {
const { navigation } = this.props
return (
<View style={styles.container}>
<SliderBox
ImageComponent={Image}
images={this.state.images}
sliderBoxHeight={200}
dotColor="red"
inactiveDotColor="#90A4AE"
paginationBoxVerticalPadding={20}
autoplay
circleLoop
resizeMethod={'resize'}
resizeMode={'cover'}
paginationBoxStyle={{
position: "absolute",
bottom: 0,
padding: 0,
alignItems: "center",
alignSelf: "center",
justifyContent: "center",
paddingVertical: 10
}}
dotStyle={{
width: 10,
height: 10,
borderRadius: 5,
marginHorizontal: 0,
padding: 0,
margin: 0,
backgroundColor: "rgba(128, 128, 128, 0.92)"
}}
ImageComponentStyle={{borderRadius: 15, width: '97%', marginTop: 25}}
/>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
},
});
Suggest any solution if you have..
Thanks.
Image change pagination at left side below image slider box..
Windas_Coder! I'm not sure if I got it, but what I understood was that you want to move the pagination dots to the bottom-left side of the content box. An easy way of doing that is to set alignSelf to flex-start inside the property paginationBoxStyle. Something like that:
paginationBoxStyle={{
alignSelf: "flex-start",
}}
So as you can read more about here, you can:
apply this property to a single child to change its alignment within its parent.
Or in another words, change only the position of the pagination box, inside the SliderBox using flex properties.
remove slider box dot.........
<SliderBox
images={this.state.images}
sliderBoxHeight={200}
onCurrentImagePressed={index => console.warn(`image ${index} pressed`)}
dotColor="#FFEE58"
inactiveDotColor="#90A4AE"
dotStyle={{
width: 0,
height:0,
borderRadius:0,
marginHorizontal:0,
padding: 0,
margin: 0
}}
/>

React Native draw custom rounded edge on View

I want to create a View which has one rounded edge on it in react native as you can see in the image. I already have the white view as I want it to be. However, it should extend up to the black curve. What are my options and how can it be achieved?
Thank you in advance.
You can make the white view elliptical by adding a bottom border radius and scaling it up using the transform attribute.
Then if you place it partially above the second view, you will end up with the expected output.
Here is an example:
import * as React from 'react';
import { View, StyleSheet } from 'react-native';
export default class App extends React.Component {
render() {
return (
<View style={styles.container}>
<View style={styles.first} />
<View style={styles.second} />
</View>
);
}
}
const styles = StyleSheet.create({
container: {
position: 'absolute',
width: '100%',
backgroundColor: '#fff',
},
first: {
backgroundColor: '#fff',
alignSelf: 'center',
width: 100,
height: 100,
borderBottomRightRadius: 50,
borderBottomLeftRadius: 50,
transform: [{ scaleX: 4 }],
zIndex: 1,
},
second: {
backgroundColor: '#333',
marginTop: -30,
height: 200,
zIndex: 0,
},
});
Here is the example in action.

React Native elevation and position absolute

Trying to add elevation (shadow) to View works, however my second View, which renders circle, hides under View with elevation property. If elevation is removed, circle with position: 'absolute' is working properly.
Any ideas how to use elevation and position View absolute?
My Code:
import React, { Component } from 'react';
import { StyleSheet, Text, View, Platform, TouchableOpacity } from 'react-native';
import { Font } from 'expo';
export default class Position extends Component {
render() {
return (
<View style={{ flex: 1, marginTop: 25 }}>
<View style={{ height: 50, backgroundColor: 'red', elevation: 3}}/>
<View style={styles.circle}><Text>HELLO</Text></View>
</View>
);
}
}
const styles = StyleSheet.create({
circle: {
position: 'absolute',
backgroundColor: 'yellow',
width: 60,
height: 60,
top: 30,
borderRadius: 100,
alignSelf: 'center',
justifyContent: 'center',
alignItems: 'center',
}
});
Found resolution by adding elevation to circle View as well.
Add shadow to circle as well and increase shadow level of circle by 1. So in your case add elevation 4 for circle.

React Native Image absolute positioning

I am trying to position two images at the bottom border, each side with the 50% width, so as to properly scale to any device size. But I can't seem to get any absolute positioning to behave in a reproducible way.
I've made an example Snack: https://snack.expo.io/rJd3OkVIM
The App component and the associated style is shown below:
import React, { Component } from 'react';
import { View, StyleSheet, Image } from 'react-native';
export default class App extends Component {
render() {
return (
<View style={styles.container}>
<Image
style={styles.img}
resizeMode="contain"
resizeMethod="resize"
source={require('./leftbg.png')}
/>
<Image
style={styles.imgr}
resizeMode="contain"
resizeMethod="resize"
source={require('./rightbg.png')}
/>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
position: 'absolute',
top: 0,
bottom: 0,
left: 0,
right: 0,
},
img: {
width: '50%',
position: 'absolute',
left: 0,
},
imgr: {
width: '50%',
position: 'absolute',
right: 0,
}
});
Each device sets the image vertical centering to a random part of the screen, every time the project is opened the centering seems to change.
To achieve your requirement, let wrap 2 images to a View with flexDirection: 'row', then make the top level View with justityContent: 'flex-end'.
I made a simple code with hard code height for 200 px and put the background as goldenrod for easy recognization.
If you need to keep the ratio of image, follow this answer: Maintain aspect ratio of image with full width in React Native
import React, { Component } from 'react';
import { View, StyleSheet, Image } from 'react-native';
export default class App extends Component {
render() {
return (
<View style={styles.container}>
<View style={{ flexDirection: 'row', height: 200, backgroundColor: 'goldenrod' }}>
<Image
style={styles.img}
source={require('./leftbg.png')}
/>
<Image
style={styles.imgr}
source={require('./rightbg.png')}
/>
</View>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
position: 'absolute',
top: 0,
bottom: 0,
left: 0,
right: 0,
justifyContent: 'flex-end',
},
img: {
width: '50%',
height: '100%',
resizeMode: 'cover',
},
imgr: {
width: '50%',
height: '100%',
resizeMode: 'cover',
}
});
You haven't given your images a vertical position reference ( top:x || bottom: x ), so this is probably why you are experiencing this behaviour.
Try setting bottom: 0 on img and imgr styles in order to set them to the bottom of the screen.