super calculadora

app.js

import React, { Component } from 'react';
import logo from './logo.svg';
import './App.css';

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      first: 0,
      second: 0,
      result: null,
      cta: 'sumar!'
    };

    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleSubmit(e) {
    const { first, second } = this.state;
    e.preventDefault();
    if (first === 0 && second === 0) {
      return;
    }

    this.setState({
      result: parseInt(first) + parseInt(second)
    }, () => this.itsDone());
  }


  itsDone() {
    this.setState({ cta: 'Fin.' })
  }

  render() {
    return (
      <div className="App">
        <header className="App-header">
          <img src={logo} className="App-logo" alt="logo" />
          <h1 className="App-title">Welcome my awesome calculator</h1>
        </header>

        <form onSubmit={this.handleSubmit}>
          <p className="App-intro">
            <input
              id="first"
              onChange={e => this.setState({ first: e.target.value })}
              value={this.state.first}
            />
          </p>
          <p className="App-intro">
            <input
              id="second"
              onChange={e => this.setState({ second: e.target.value })}
              value={this.state.second}
            />
          </p>
          <p className="App-intro">
            {this.state.result && (<h1>{this.state.result}</h1>)}
            <button>{this.state.cta}</button>
          </p>
        </form>
      </div>
    );
  }
}

export default App;