Class App

code/composition/src/app.jsx:26–38

};

class App extends React.Component {
  render() {
    return (
      <Header track={ this._track } title={ <Title /> }>
        <Navigation track={ this._track } />
        <DataProvider render={ message => <p>{ message }</p> } />
      </Header>
    );
  }
  _track(label) {
    console.log(`Tracking: ${ label }`);
  }
};

ReactDOM.render(<App />, document.querySelector('#container'));