App.js

class App extends Component {

  constructor() {
    super()
    this.state = {name: 'Say my name'}
  }

  handleName(newName) {
    this.setState({ name: newName});
  }

  render() {
    return (
        <div className="App">
          <Child name={this.state.name} onNameChange={this.handleName.bind(this)}/>
        </div>
    );
  }
}

export default App;