How to show loading progress or spinner in the middle of the screen with React Native? - react-native

Question

I am developing React Native app.
I was able to solve all problems by myself but this is exception.
I am going to load another screen with bottom tab navigator.
For example, after user login to the app, it should show main home screen which has many pictures and many style sheet effects, icons. Because of that, after login confirm ( I mean after alert of the login confirm), the main home screen appears after a few seconds.
So I want to show some spinner in the login screen while loading main home screen in the background and when it is ready to show, erase spinner and show main home screen.
How can I do this?
My bottom tab navigator was simply created with createBottomTabNavigator() method.

Answer 1

So in your case you can do several things
You can use React Native Activity Indicator -> View
You can use Overlay Library -> react-native-loading-spinner-overlay -> View GitHub
If you like to make loading like facebook / instagram -> then use react-native-easy-content-loader -> View GitHub
Assume that you are using React Native Activity Indicator :
import { ActivityIndicator } from "react-native";
export default class HomeScreen extends Component {
constructor(props) {
super(props);
this.state = {
isLoading: true
};
}
//Get Home Screen Data API Action
componentDidMount() {
this.loadAPI(); // Call home screen get data API function
}
//Login API Function
loadAPI = () => {
this.setState({ isLoading: true }); // Once You Call the API Action loading will be true
fetch(API_URL, {
method: "POST",
headers: {
"Content-Type": "application/json"
}
})
.then(response => response.json())
.then(responseText => {
// You can do anything accroding to your API response
this.setState({ isLoading: false }); // After getting response make loading to false
})
.catch(error => {});
};
render() {
return (
<View style={{ flex: 1, justifyContent: "center", alignItems: "center" }}>
{this.state.isLoading && <ActivityIndicator color={"#fff"} />}
</View>
);
}
}
If you want to hide all the view until loading finish like images, so you can use custom library instead of Activity Indicator.

Answer 2

I have created my custom Loader component. Using this you can display built in ActivityIndicator or your custom gif loader image with overlay.
Loader.js
import React, { Component } from 'react';
import {
StyleSheet,
View,
Modal,
Image,
ActivityIndicator
} from 'react-native';
class Loader extends Component {
constructor(props) {
super(props);
this.state = {
isLoading: this.props.isLoading
}
}
static getDerivedStateFromProps(nextProps) {
return {
isLoading: nextProps.isLoading
};
}
render() {
return (
<Modal
transparent={true}
animationType={'none'}
visible={this.state.isLoading}
style={{ zIndex: 1100 }}
onRequestClose={() => { }}>
<View style={styles.modalBackground}>
<View style={styles.activityIndicatorWrapper}>
<ActivityIndicator animating={this.state.isLoading} color="black" />
{/* If you want to image set source here */}
{/* <Image
source={require('../assets/images/loader.gif')}
style={{ height: 80, width: 80 }}
resizeMode="contain"
resizeMethod="resize"
/> */}
</View>
</View>
</Modal>
)
}
}
const styles = StyleSheet.create({
modalBackground: {
flex: 1,
alignItems: 'center',
flexDirection: 'column',
justifyContent: 'space-around',
backgroundColor: '#rgba(0, 0, 0, 0.5)',
zIndex: 1000
},
activityIndicatorWrapper: {
backgroundColor: '#FFFFFF',
height: 100,
width: 100,
borderRadius: 10,
display: 'flex',
alignItems: 'center',
justifyContent: 'space-around'
}
});
export default Loader
Now you can use it when you have to display loading indicator as below :
<Loader isLoading={this.state.isLoading} />

Answer 3

import { ActivityIndicator } from 'react-native';
export default class LoginScreen extends Component {
constructor(props) {
super(props);
this.state = {
spinner : true
}
}
render() {
return (
<View style={{flex : 1, justifyContent: 'center', alignItems: 'center',}}>
{
this.state.spinner &&
<ActivityIndicator color={'#fff'} />
}
</View>
)
}
}

Answer 4

So you can show the SPinner for suppose when you have to load an API or something and when you get the response of api, you can set spinner loading value to false.
For eg :
import {View, ActivityIndicator } from 'react-native';
export default class MainScreen extends React.Component {
constructor(props) {
super(props);
this.state = {
spinner : true
}
}
componentDidMount(){
this.loadApi();
}
loadApi = async() => {
let result = axios.get('url').then((data) =>{
this.setState({spinner:false});
}
).catch((err) => this.setState({spinner:false})
}
render() {
return (
<View style={{flex : 1, justifyContent: 'center', alignItems: 'center',}}>
{
this.state.spinner? <ActivityIndicator color={'#fff'} />:<View><Text>Data loaded</Text></View>
}
</View>
)
}
}

Answer 5

you have to use ActivityIndicator you can have to load this activityindicator before getting data from the server , you have to check below code hope you will understand
import React, {useEffect, useState} from 'react';
import {ActivityIndicator, View, Dimensions} from 'react-native';
import HomeScreen from './Home';
const DataViewer = () => {
const [data, setData] = useState([]);
const {height, width} = Dimensions.get('window');
useEffect(() => {
fetch('http://example.com/movies.json')
.then(response => {
return response.json();
})
.then(myJson => {
setData(myJson);
});
});
return data.length > 0 ? (
<HomeScreen data={data} />
) : (
<View
style={{justifyContent: 'center', alignItems: 'center', height, width}}>
<ActivityIndicator size="large" color="#0000ff" />
</View>
);
};
export default DataViewer;

Answer 6

You can use the Activity indicator as the default loading animation. But you can also use Lottie files to implement custom loading screen animation on your project by installing npm i lottie-react-native or yarn add lottie-react-native