text: import React, {Component} from 'react';
  import 'bootstrap/dist/css/bootstrap.css';
  import '../style/Navbar.css';
  import registerServiceWorker from './../registerServiceWorker';
  
  /**
  * This class contains all needed to display the nav bar on top.
  */
  export default class NavbarUsuario extends Component {
    constructor(props) {
      super(props);
      
      this.state = {
        onChange: props.onChange,
        onLogOut: props.onLogOut
      };
  
    }
    
    render() {
      return (
        <div className='fixed-top'>
          <nav id='navbar_home' className='nav navbar-light'>
            <a id='nombre_nav' className='col-md-7 navbar-brand hvr-underline-from-center' 
              onClick={this.state.onChange.bind(this, 'UsuarioFacturas')} href={'#'}>
              <img src={require('./../img/newsletter.png')} width='30' height='30'
                className='d-inline-block align-top' alt='logo'/> Factura Electronica
            </a>
            <a className='nav-item nav-link ' href={'#'} onClick={this.state.onChange.bind(this, 'UsuarioFacturas')}>Facturas</a>
            <a className='nav-item nav-link ' href={'#'} onClick={this.state.onChange.bind(this, 'UsuarioProductos')}>Productos</a>
            <a className='nav-item nav-link ' href={'#'} onClick={this.state.onLogOut.bind(this)}>Log Out</a>
          </nav>
        
        </div>
      );
    }
  }
    
    
  registerServiceWorker();