react-context-decorator-2.js

const { provider, consumer } = createDecorator();

@provider('red')
class App extends React.Component {
  render() {
    return <Button />;
  }
}

@consumer('color')
class Button extends React.Component {
  render() {
    return (
      <button
        style={{ color: this.props.color }}
        onClick={() => this.props.setColor('green')}>
        Click Me!
      </button>
    );
  }
}

// ...