The animations are an important part of the UX of an app, and interacting with the user using the animations create a better experience for the user, the most successful user experience are made with animations, that’s why we are goin to play around animations in React Native, technically React Native provide a great animations API that give us the ability to do different transitions and the animations .
New to React Native? check my article introduction to React Native check this out!
You may want how to style a React Native app and the options you can use to do the Job check Styling in React Native.
Now, what are we gonna is create animations like Fade
,slideUp
, slideDown
, rotate
..etc. using the animations API.
A good to mention we will be comparing the examples we are going to create with rnal (react native animations library) the library I’ve created a library that does that all the kind of the animations you may want use.
First, of all to start using animations, we are using Animated
module that react-native provides to do the magic things for us
When building components, I’d advise using Bit to share and manage them across projects as a team- so you can build faster and stay in sync. Try it:
React animations as Bit components: reusable building blocks
import {Animated} from "react-native";
Let’s start first with Fade
:Fade animation
The Animated
method takes parameters as values and turns those values into animated values then we can use those values to animate our
Components, okay! show me the code!
import React, { Component } from "react"; import { Text, View, StyleSheet, Animated, TouchableOpacity } from "react-native";export default class Fade extends Component { state = { fadeValue: new Animated.Value(0) }; _start = () => { Animated.timing(this.state.fadeValue, { toValue: 1, duration: 1000 }).start(); }; render() { return ( <View style={styles.container}> <TouchableOpacity style={styles.btn} onPress={() => this._start()}> <Text style={styles.textBtn}>Start</Text> </TouchableOpacity> <Animated.View style={{ opacity: this.state.fadeValue, height: 250, width: 200, margin: 5, borderRadius: 12, backgroundColor: "#347a2a", justifyContent: "center" }} > <Text style={styles.text}>Fade </Text> </Animated.View> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: "#FFF", alignItems: "center", justifyContent: "center" }, item: {}, btn: { backgroundColor: "#480032", width: 100, height: 40, padding: 3, justifyContent: "center", borderRadius: 6 }, text: { fontSize: 20, color: "#fff", fontWeight: "bold", textAlign: "center" }, item1: { backgroundColor: "red", padding: 20, width: 100, margin: 10 }, textBtn: { color: "#f4f4f4", fontWeight: "bold", textAlign: "center" } });
Let’s break it down!
First, we need to initialize a value so we can give this value to the Animated
method :
state = {fadeValue: Animated.Value(0)
};
Then let’s create a function called _start
that will start our animations:
_start = () => {return Animated.timing(this.state.fadeValue, {
toValue: 1, // output
duration: 3000, // duration of the animation
}).start();
};
What we just did here? we used timing
method from Animated
, it takes some values:
start()
callback that starts the animations!Now we have an animated value, the next step is to use it to animate the component. we use Animated.View
as a wrapper to our component in order to make the animations happen !
<Animated.Viewstyle={{
opacity: this.state.fadeValue,
height: 250,
width: 200,
margin: 5,
borderRadius: 12,
backgroundColor: “#347a2a”,
justifyContent: “center”
}}
>
<Text style={styles.text}>Fade </Text>
</Animated.View>
You see we passed the fadeValue
to the opacity property so we can handle the opacity of the element so when the component start appears it happens smoothly and in an animated behavior! and that gives us the fade
animation !
Now let’s call the _start()
function when an action is taken , in our case we call the function when button
is clicked. you can trigger the function whenever you like for example within componentDidMount()
.
<TouchableOpacity style={styles.btn} onPress={() => this._start()}>
rnal made things for us more easy to create the fade animation:
First, let’s install the package :
With Yarn
hit yarn add rnal
, or npm
run npm i rnal
Then Import The Fade
element :
import React, { Component } from “react”;
import {
Text,
View,
StyleSheet,
Animated,
TouchableOpacity
} from “react-native”;
import { Fade } from “rnal”;export default class MyComponent extends Component { state = { ready: false }; render() { return ( <View style={styles.container}> <TouchableOpacity style={styles.btn} onPress={() => this.setState({ ready: true })} > <Text style={styles.textBtn}>Start</Text> </TouchableOpacity> <Fade startWhen={this.state.ready}> <View style={{ height: 250, width: 200, margin: 5, borderRadius: 12, backgroundColor: "#347a2a", justifyContent: "center" }} /> <Text style={styles.text}>Fade </Text> <View /> </Fade> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: "#FFF", alignItems: "center", justifyContent: "center" }, item: {}, btn: { backgroundColor: "#480032", width: 100, height: 40, padding: 3, justifyContent: "center", borderRadius: 6 }, text: { fontSize: 20, color: "#fff", fontWeight: "bold", textAlign: "center" }, item1: { backgroundColor: "red", padding: 20, width: 100, margin: 10 }, textBtn: { color: "#f4f4f4", fontWeight: "bold", textAlign: "center" } });
And:
Fade has startWhen
props, it’s a type of boolean
and it determines when the animation should start by default it starts when the component mount, you can discover more options to customize your animations
Let’s try with something more awesome like making the component goes from the bottom or SlideDown
animation. we will use the same code above but we need to change some values! and we will use interpolate
method to interpolate the AnimatedValue cool let’s do it
import React, { Component } from “react”;
import {
Text,
View,
StyleSheet,
Animated,
TouchableOpacity
} from “react-native”;
import { Fade } from “rnal”;export default class MyComponent extends Component { state = { ready: false, animatedValue: new Animated.Value(0) }; _start = () => { Animated.timing(this.state.animatedValue, { toValue: 1, duration: 1000 }).start(); }; render() { let { animatedValue } = this.state; return ( <View style={styles.container}> <TouchableOpacity style={styles.btn} onPress={() => this._start()}> <Text style={styles.textBtn}>Start</Text> </TouchableOpacity> <Animated.View style={{ transform: [ { translateY: animatedValue.interpolate({ inputRange: [0, 1], outputRange: [-600, 0] }) } ], height: 250, width: 200, margin: 5, borderRadius: 12, backgroundColor: "#347a2a", justifyContent: "center" }} /> <Text style={styles.text}>Fade </Text> <Animated.View /> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: "#FFF", alignItems: "center", justifyContent: "center" }, item: {}, btn: { backgroundColor: "#480032", width: 100, height: 40, padding: 3, justifyContent: "center", borderRadius: 6 }, text: { fontSize: 20, color: "#fff", fontWeight: "bold", textAlign: "center" }, item1: { backgroundColor: "red", padding: 20, width: 100, margin: 10 }, textBtn: { color: "#f4f4f4", fontWeight: "bold", textAlign: "center" } });
Replace gif with the slideDown animation
The interpolate
method takes an Object of properties.
inputRange
: The start point of the animatedValue
: for example, we want the translateX
to start from 1 level :inputRange:[0,1]
outputRange
: gives us an outputRange based on the inputRange
transform:[{translateY:animatedValue.interpolate({
inputRange:[0,1],
outputRange:[-600,0]})}
]
Doing the same with react-native-animations-library! is more much simple, there is theSlideDown
element so you can wrap the component you want to animate!
import React, { Component } from “react”;
import {
Text,
View,
StyleSheet,
Animated,
TouchableOpacity
} from “react-native”;
import { Fade, SlideDown } from “rnal”;export default class MyComponent extends Component { state = { ready: false }; render() { let { animatedValue } = this.state; return ( <View style={styles.container}> <TouchableOpacity style={styles.btn} onPress={() => this.setState({ ready: true })} > <Text style={styles.textBtn}>Start</Text> </TouchableOpacity> <SlideDown startWhen={this.state.ready} duration={1000} style={{ height: 250, width: 200, margin: 5, borderRadius: 12, backgroundColor: "#347a2a", justifyContent: "center" }} /> <Text style={styles.text}>Fade </Text> <SlideDown /> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: "#FFF", alignItems: "center", justifyContent: "center" }, item: {}, btn: { backgroundColor: "#480032", width: 100, height: 40, padding: 3, justifyContent: "center", borderRadius: 6 }, text: { fontSize: 20, color: "#fff", fontWeight: "bold", textAlign: "center" }, item1: { backgroundColor: "red", padding: 20, width: 100, margin: 10 }, textBtn: { color: "#f4f4f4", fontWeight: "bold", textAlign: "center" } });
There are cases when need to make the animations to run indefinitely, Animated gives us Animated.loop()
method to make this happen let’s see how it works! the best example to demonstrate that is to create a spinner!
import React, { Component } from “react”;
import {
Text,
View,
StyleSheet,
Animated,
TouchableOpacity
} from “react-native”;export default class Infinite extends Component { state = { rotateValue: new Animated.Value(0) }; componentDidMount() { this._start(); } _start = () => { Animated.loop( Animated.timing(this.state.rotateValue, { toValue: 1, duration: 400, Infinite: true }) ).start(); }; render() { return ( <View style={styles.container}> <Animated.View style={{ transform: [ { rotate: this.state.rotateValue.interpolate({ inputRange: [0, 1], outputRange: ["0deg", "380deg"] }) } ], height: 50, width: 50, margin: 5, borderWidth: 2, borderColor: "#888", borderBottomColor: "#8bffff", borderRadius: 50, justifyContent: "center" }} /> <Text style={styles.text}>Fade </Text> <Animated.View /> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: "#FFF", alignItems: "center", justifyContent: "center" }, item: {}, btn: { backgroundColor: "#480032", width: 100, height: 40, padding: 3, justifyContent: "center", borderRadius: 6 }, text: { fontSize: 20, color: "#fff", fontWeight: "bold", textAlign: "center" }, item1: { backgroundColor: "red", padding: 20, width: 100, margin: 10 }, textBtn: { color: "#f4f4f4", fontWeight: "bold", textAlign: "center" } });
Here we go!
What we just did is give the Animated.loop
our animations as an argument to run it in a loop cycle.
With react-native animation library(rnal), you can just addinifinite
props to make this happen!
import { Rotate } from “rnal”;<Rotate infinite>
<View
style={{
height: 50,
width: 50,
margin: 5,
borderWidth: 2,
borderColor: “#888”,
borderBottomColor: “#8bffff”,
borderRadius: 50,
justifyContent: “center”
}}
/>
<Text style={styles.text}>Fade </Text>
<View />
</Rotate>
If you take a look at the examples above, we don’t actually change much, the same function we just determine where we use then animatedValue
yeah it’s all about a value transformed to an animated value and allow us to do the animation we want using translate,scale, rotate
and all other supported animations
That was the way we run a single animation what about making a group of animations? sequence
and parallel
methods got you covred!
Run a group of animationsWe can usesequence
or parallel
methods to run a group of animations, the two methods do almost the same job, the only difference is that parallel run the group of animations at once whereas the sequence
method blocks the next animation until the previous animation is finished and done, and if one of the animations stops or break the next animation won’t be able to run.
import React, { Component } from “react”;
import {
Text,
View,
StyleSheet,
Animated,
TouchableOpacity
} from “react-native”;export default class MyComponent extends Component { state = { ready: false, SlideInLeft: new Animated.Value(0), slideUpValue: new Animated.Value(0), fadeValue: new Animated.Value(0) }; _start = () => { return Animated.parallel([ Animated.timing(this.state.SlideInLeft, { toValue: 1, duration: 500, useNativeDriver: true }), Animated.timing(this.state.fadeValue, { toValue: 1, duration: 500, useNativeDriver: true }), Animated.timing(this.state.slideUpValue, { toValue: 1, duration: 500, useNativeDriver: true }) ]).start(); }; render() { let { slideUpValue, fadeValue, SlideInLeft } = this.state; return ( <View style={styles.container}> <TouchableOpacity style={styles.btn} onPress={() => this._start()}> <Text style={styles.textBtn}>Start</Text> </TouchableOpacity> <Animated.View style={{ transform: [ { translateX: slideUpValue.interpolate({ inputRange: [0, 1], outputRange: [-600, 0] }) } ], flex: 1, height: 250, width: 200, borderRadius: 12, backgroundColor: "#c00", justifyContent: "center" }} > <Text style={styles.text}>SlideUp </Text> </Animated.View> <Animated.View style={{ transform: [ { translateY: SlideInLeft.interpolate({ inputRange: [0, 1], outputRange: [600, 0] }) } ], flex: 1, height: 250, width: 200, borderRadius: 12, backgroundColor: "#347a2a", justifyContent: "center" }} > <Text style={styles.text}>SlideInLeft </Text> </Animated.View> <Animated.View style={{ opacity: fadeValue, flex: 1, height: 250, width: 200, borderRadius: 12, backgroundColor: "#f4f", justifyContent: "center" }} > <Text style={styles.text}>Fade </Text> </Animated.View> </View> ); } } const styles = StyleSheet.create({ container: { flex: 1, backgroundColor: "#FFF", alignItems: "center" }, item: {}, btn: { backgroundColor: "#480032", width: 100, height: 40, padding: 3, justifyContent: "center", borderRadius: 6, marginTop: 29 }, text: { fontSize: 20, color: "#fff", fontWeight: "bold", textAlign: "center" }, item1: { backgroundColor: "red", padding: 20, width: 100, margin: 10 }, textBtn: { color: "#f4f4f4", fontWeight: "bold", textAlign: "center" } });
parallel
method:With sequence
:
Ggenerally, there is much to talk about React Native animations and it’s a huge subject we won’t be able to cover it in one post we will have a chance to talk about other parts in upcoming articles but anyway we just covered the most parts of it and you will be able to create your own animations after reading this article. you can always use the react-native animations library I’ve created it’s so simple and easy to use. Thanks for reading. Keep Visiting
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