I have implemented this using Animated library in native react-native where I interpolate when I am scrolling. The problem is it is very laggy on ios and somewhat laggy on android. Is there a library or a better way to do this header hiding when scrolling in react-native ?
Here is my current implementation:
const scrollY = new Animated.Value(0);
const diffClamp = Animated.diffClamp(scrollY, 0, HEADER_HEIGHT);
const translateY = diffClamp.interpolate({
inputRange: [0, HEADER_HEIGHT],
outputRange: [0, -HEADER_HEIGHT],
});
return (
<ExploreHeader
...
translateY={translateY}
/>
<ExploreData
...
scrollY={scrollY}
offset={HEADER_HEIGHT}
scrollRef={scrollRef}
/>
and in ExploreHeader I have this:
<Animated.View
style={{
position: 'absolute',
top: 0,
right: 0,
left: 0,
height: height,
transform: [{translateY: translateY}],
elevation: 100,
zIndex: 100,
}}>
and in ExploreData:
<FlatList
...
onScroll={(e) => {
scrollY.setValue(e.nativeEvent.contentOffset.y);
}}
style={{paddingTop: offset}}
/>
Related
How can we set a Navigation Bar at the bottom of the page in react native using View and components (if you want)!! with any tag of react-native npm - (/or else) you want!!
EX:
The Page Home :
----Header----
---- your tags (Screens)----
----Footer----
let us to do this -->-->-->
let us use this tag (View) then set styles on it.
...
return (
<View style={styles.parantTagStyle}>
<View>
{
this.chechreturnedScreen()
}
</View>
<View style={styles.footerTagStyle}>
<TabBottom navigatorFunction={this.navPages} headerTitle={this.state.headerTitle} />
</View>
</View>
);
and use this style :
const styles = StyleSheet.create({
parantTagStyle: {
left: 0,
bottom: 0,
right: 0,
flex:1
},
footerTagStyle: {
position: 'absolute',
left: 0,
bottom: 0,
right: 0,
},
});
...
App with scroll
In the image I have drawn you can see two areas, the yellow one is a ScrollView, and the red one is a flatlist.
When I scroll from the red zone, I want the tabs to go up to the header, and once they touch the header, start scrolling the red zone of FlatList.
To do this, when the tabs touch the header I set the scrollEnabled from the yellow zone to false, the problem is that the red zone doesn't scroll until I stop pressing and press again.
The behavior I want it to have is similar to the instagram profile, where there are some tabs and then a list of photos, when the tabs touch the header, you can continue scrolling from the images.
I'll add a few options
First one is a snack, which again uses parent and child scrollviews
Collapsible Header Tabs Snack
Problems: This has issues on Android. the scroll stutters on android while both parent and child scrollviews are scrolling.
Second is github repo React-Native-Collapsing-TabView
Problems: if one of the tab is scrolled and you go to another tab then there will white space on top.issue
Using Native Base.
import React, {Component} from "react";
import {Animated, Dimensions, Platform, Text, TouchableOpacity, View} from "react-native";
import {Body, Header, List, ListItem as Item, ScrollableTab, Tab, TabHeading, Tabs, Title} from "native-base";
import LinearGradient from "react-native-linear-gradient";
const {width: SCREEN_WIDTH} = Dimensions.get("window");
const IMAGE_HEIGHT = 250;
const HEADER_HEIGHT = Platform.OS === "ios" ? 64 : 50;
const SCROLL_HEIGHT = IMAGE_HEIGHT - HEADER_HEIGHT;
const THEME_COLOR = "rgba(85,186,255, 1)";
const FADED_THEME_COLOR = "rgba(85,186,255, 0.8)";
export default class ParallaxDemo extends Component {
nScroll = new Animated.Value(0);
scroll = new Animated.Value(0);
textColor = this.scroll.interpolate({
inputRange: [0, SCROLL_HEIGHT / 5, SCROLL_HEIGHT],
outputRange: [THEME_COLOR, FADED_THEME_COLOR, "white"],
extrapolate: "clamp"
});
tabBg = this.scroll.interpolate({
inputRange: [0, SCROLL_HEIGHT],
outputRange: ["white", THEME_COLOR],
extrapolate: "clamp"
});
tabY = this.nScroll.interpolate({
inputRange: [0, SCROLL_HEIGHT, SCROLL_HEIGHT + 1],
outputRange: [0, 0, 1]
});
headerBg = this.scroll.interpolate({
inputRange: [0, SCROLL_HEIGHT, SCROLL_HEIGHT + 1],
outputRange: ["transparent", "transparent", THEME_COLOR],
extrapolate: "clamp"
});
imgScale = this.nScroll.interpolate({
inputRange: [-25, 0],
outputRange: [1.1, 1],
extrapolateRight: "clamp"
});
imgOpacity = this.nScroll.interpolate({
inputRange: [0, SCROLL_HEIGHT],
outputRange: [1, 0],
});
tabContent = (x, i) => <View style={{height: this.state.height}}>
<List onLayout={({nativeEvent: {layout: {height}}}) => {
this.heights[i] = height;
if (this.state.activeTab === i) this.setState({height})
}}>
{new Array(x).fill(null).map((_, i) => <Item key={i}><Text>Item {i}</Text></Item>)}
</List></View>;
heights = [500, 500];
state = {
activeTab: 0,
height: 500
};
constructor(props) {
super(props);
this.nScroll.addListener(Animated.event([{value: this.scroll}], {useNativeDriver: false}));
}
render() {
return (
<View>
<Animated.View style={{position: "absolute", width: "100%", backgroundColor: this.headerBg, zIndex: 1}}>
<Header style={{backgroundColor: "transparent"}} hasTabs>
<Body>
<Title>
<Animated.Text style={{color: this.textColor, fontWeight: "bold"}}>
Tab Parallax
</Animated.Text>
</Title>
</Body>
</Header>
</Animated.View>
<Animated.ScrollView
scrollEventThrottle={5}
showsVerticalScrollIndicator={false}
onScroll={Animated.event([{nativeEvent: {contentOffset: {y: this.nScroll}}}], {useNativeDriver: true})}
style={{zIndex: 0}}>
<Animated.View style={{
transform: [{translateY: Animated.multiply(this.nScroll, 0.65)}, {scale: this.imgScale}],
backgroundColor: THEME_COLOR
}}>
<Animated.Image
source={{uri: "https://upload.wikimedia.org/wikipedia/commons/c/c5/Moraine_Lake_17092005.jpg"}}
style={{height: IMAGE_HEIGHT, width: "100%", opacity: this.imgOpacity}}>
{/*gradient*/}
{/* <LinearGradient
colors={["rgba(255,255,255,0.9)", "rgba(255,255,255,0.35)", "rgba(255,255,255,0)"]}
locations={[0, 0.25, 1]}
style={{position: "absolute", height: "100%", width: "100%"}}/> */}
</Animated.Image>
</Animated.View>
<Tabs
prerenderingSiblingsNumber={3}
onChangeTab={({i}) => {
this.setState({height: this.heights[i], activeTab: i})
}}
renderTabBar={(props) => <Animated.View
style={{transform: [{translateY: this.tabY}], zIndex: 1, width: "100%", backgroundColor: "white"}}>
<ScrollableTab {...props}
renderTab={(name, page, active, onPress, onLayout) => (
<TouchableOpacity key={page}
onPress={() => onPress(page)}
onLayout={onLayout}
activeOpacity={0.4}>
<Animated.View
style={{
flex: 1,
height: 100,
backgroundColor: this.tabBg
}}>
<TabHeading scrollable
style={{
backgroundColor: "transparent",
width: SCREEN_WIDTH / 2
}}
active={active}>
<Animated.Text style={{
fontWeight: active ? "bold" : "normal",
color: this.textColor,
fontSize: 14
}}>
{name}
</Animated.Text>
</TabHeading>
</Animated.View>
</TouchableOpacity>
)}
underlineStyle={{backgroundColor: this.textColor}}/>
</Animated.View>
}>
<Tab heading="Tab 1">
{this.tabContent(30, 0)}
</Tab>
<Tab heading="Tab 2">
{this.tabContent(15, 1)}
</Tab>
</Tabs>
</Animated.ScrollView>
</View>
)
}
}
Problems: All screens scrolling because of same offset
Fourth is a module Sticky parallax header you can use tabbed header from here
Problems: Since its module not a lot of room for customization, but there are enough. And also when i was using it there were some issues like all screens scrolling because of same offset which might have been solved now.
So basically speaking all of them have some problems that you will have to solve later on.
But I would recommend the 4th option using the sticky-parallax-header by netguru.
I am trying to use a Gesture handler with a functional component. The problem is when I drag for the second time it's dragging from initial position again
This is my code below
let translateXRef = useRef(new Animated.Value(0)).current;
const onGestureEvent = useCallback(
Animated.event(
[
{
nativeEvent: {
translationX: translateXRef,
},
},
],
{ useNativeDriver: true }
),
[]
);
<View
style={{
backgroundColor: '#FFFFFF80',
position: 'absolute',
top: 0,
bottom: 0,
left: 0,
right: 0,
height: 100,
}}
>
<PanGestureHandler
onGestureEvent={onGestureEvent}
onHandlerStateChange={onHandlerStateChange}
>
<Animated.View
// eslint-disable-next-line react-native/no-inline-styles
style={{
height: '100%',
width: 10,
backgroundColor: AppColors.buttonColor,
transform: [{ translateX: translateXRef }],
}}
/>
</PanGestureHandler>
</View>
You need to use the context in addition to the event in your callback.
I'm not sure why you're using the Animated.event. You should generate your callbacks using the useAnimatedGestureHandler.
Each of those callbacks onStart, onActive, onEnd, etc... take an event and context argument.
The context argument is an object that would let you set your previous position so that then next click would not reset the position.
Here's more info:
https://docs.swmansion.com/react-native-reanimated/docs/fundamentals/events/#using-context
Also, a pretty good video that explains it:
https://youtu.be/4HUreYYoE6U
So Ideally, When i scroll down, I want the header to disappear(slide down) and when I scroll up I want it to show (slide up). Idc where im at in the page. I just want the animation to fire when those 2 events occur. I see some apps have this but I can't think of how to replicate it. please help me set a basis for this
You can use Animated.FlatList or Animated.ScrollView to make the scroll view, and attach a callback to listen onScroll event when it is changed. Then, using interpolation to map value between y-axis and opacity.
searchBarOpacityAnim is a component's state. By using Animated.event, the state will be updated when a callback is called. Also, don't forget to set useNativeDriver to be true. I've attached the link to document below about why you have to set it.
<Animated.FlatList
...
onScroll={Animated.event(
[{ nativeEvent: { contentOffset: { y: searchBarOpacityAnim } } }],
{ useNativeDriver: true },
)}
...
/>
Then, use Animated.View wraps your component which you want to animate it. Use .interpolate to map value between the state and component's opacity like the example below...
<Animated.View
style={{
opacity: searchBarOpacityAnim.interpolate({
inputRange: [213, 215],
outputRange: [0, 1],
}),
}}
>
<SearchBar />
</Animated.View>
You can read more information about useNativeDriver, .interpolate, and Animated.event here.
https://facebook.github.io/react-native/docs/animated#using-the-native-driver
https://facebook.github.io/react-native/docs/animations#interpolation
https://facebook.github.io/react-native/docs/animated#handling-gestures-and-other-events
You can use Animated from 'react-native'
here an example changing the Topbar height:
import { Animated } from 'react-native';
define maxHeight and minHeight topbar
const HEADER_MAX_HEIGHT = 120;
const HEADER_MIN_HEIGHT = 48;
initialize a variable with the scrollY value
constructor(props) {
super(props);
this.state = {
scrollY: new Animated.Value(
Platform.OS === 'ios' ? -HEADER_MAX_HEIGHT : 0,
),
};
}
on render you can interpolate a value acording the scrollY Value
render() {
const { scrollY } = this.state;
// this will set a height for topbar
const headerHeight = scrollY.interpolate({
inputRange: [0, HEADER_MAX_HEIGHT - HEADER_MIN_HEIGHT],
outputRange: [HEADER_MAX_HEIGHT, HEADER_MIN_HEIGHT],
extrapolate: 'clamp',
});
// obs: the inputRange is the scrollY value, (starts on 0)
// and can go until (HEADER_MAX_HEIGHT - HEADER_MIN_HEIGHT)
// outputRange is the height that will set on topbar
// obs: you must add a onScroll function on a scrollView like below:
return (
<View>
<Animated.View style={{
position: 'absolute',
top: 0,
left: 0,
right: 0,
backgroundColor: '#2e4265',
height: headerHeight,
zIndex: 1,
flexDirection: 'row',
justifyContent: 'flex-start',
}}>
<Text>{title}</Text>
</Animated.View>
<ScrollView
style={{ flex: 1 }}
scrollEventThrottle={16}
onScroll={Animated.event(
[{ nativeEvent: { contentOffset: { y: this.state.scrollY } } }],
)}>
<View style={{ height: 1000 }} />
</ScrollView>
</View>
);
}
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.