ReactJS: setTimeout() not working?

Question

Having this code in mind:

var Component = React.createClass({

    getInitialState: function () {
        return {position: 0};    
    },

    componentDid         


        

Answer 1

There's a 3 ways to access the scope inside of the 'setTimeout' function

First,

const self = this
setTimeout(function() {
  self.setState({position:1})
}, 3000)

Second is to use ES6 arrow function, cause arrow function didn't have itself scope(this)

setTimeout(()=> {
   this.setState({position:1})
}, 3000)

Third one is to bind the scope inside of the function

setTimeout(function(){
   this.setState({position:1})
}.bind(this), 3000)