SomeStatefulComponent.js

/**
 * See http://facebook.github.io/react/docs/component-specs.html
 */
const SomeStatefulComponent = React.createClass({

  // Define the initial "state" of our component
  // Update state via this.setState({loading: true})
  getInitialState() {
    return {
      loading: false,
    };
  },

  // Make use of lifecycle hooks such as "request messages (Ajax) on did mount"
  componentDidMount() {
    const {messages, requestMessages} = this.props;
    if (messages.length <= 1) {
      requestMessages();
    }
  },
  
  // ...
  
  render() {
    // We have access to this.props as well as this.state
    return (
      <div>
        <h1>Hello, I am SomeStatefulComponent!</h1>
        <h3>{this.props.message}</h3>
        // Only render children when we are not loading
        {this.state.loading ? 'Loading...' : this.props.children}
      </div>
    )
  }
});