observable

observable.js

import {View} from 'react-native';
import React, { Component } from 'react';

function randomColor() {
    return '#'+Math.floor(Math.random()*16777215).toString(16);
}

export default class HelloWorld extends Component {

    constructor() {
        super();

        // Set initial state here
        this.state = {
            bg: randomColor(),
        };

        this.setTimeout(()=> { this.setState({bg: randomColor()})}, 5000);
    }

    render() {
        <View style={{flex:1, backgroundColor: this.state.bg}}/ >
    }

}