What is the difference between using constructor vs getInitialState in React / React Native?

Question

I\'ve seen both used interchangeably.

What are the main use cases for both? Are there advantages / disadvantages? Is one a better practice?

Answer 1

If you are writing React-Native class with ES6, following format will be followed. It includes life cycle methods of RN for the class making network calls.

import React, {Component} from 'react';
import {
     AppRegistry, StyleSheet, View, Text, Image
     ToastAndroid
} from 'react-native';
import * as Progress from 'react-native-progress';

export default class RNClass extends Component{
     constructor(props){
          super(props);

          this.state= {
               uri: this.props.uri,
               loading:false
          }
     }

     renderLoadingView(){
          return(
               
                    
                    
                        Loading Data...
                    
               
          );
     }

     renderLoadedView(){
          return(
               

               
          );
     }

     fetchData(){
          fetch(this.state.uri)
               .then((response) => response.json())
               .then((result)=>{

               })
               .done();

               this.setState({
                         loading:true
               });
               this.renderLoadedView();
     }

     componentDidMount(){
          this.fetchData();
     }

     render(){
          if(!this.state.loading){
               return(
                    this.renderLoadingView()
               );
          }

          else{

               return(
                    this.renderLoadedView()
               );
          }
     }
}

var style = StyleSheet.create({

});