How do I check if the user clicked inside the current component?

Question

I have a component called Dialog, in which I attach an event listener on mouse clicks on the window object.

componentDidMount() {
    document.addEventListener('click', this.handleClick);
}

componentWillUnmount() {
    document.removeEventListener('click', this.handleClick);
}

How can I detect (in the handleClick function) whether a click has been fired inside the component or outside? Note that this dialog contains different elements and child components.

Answer 1

parent.contains(child) is your friend. This solution using refs might not be perfect, but simply using this does not work as it's not a proper DOM node. I'm using React 15 here, so keep in mind that in earlier versions you'd have to use .getDOMNode() on the parent.

class Dialog extends React.Component {
  constructor() {
    super();
    this.handleClick = this.handleClick.bind(this);
  }
  componentDidMount() {
    document.addEventListener('click', this.handleClick);
  }
  componentWillUnmount() {
    document.removeEventListener('click', this.handleClick);
  }
  handleClick(e) {
    if (this.node.contains(e.target)) {
      console.log('You clicked INSIDE the component.')
    } else {
      console.log('You clicked OUTSIDE the component.')
    }
  }
  render() {
    return(
      <span ref={node => this.node = node}>
        Level 0<br/>
        <span>
          Level 1.<br/>
          <span>Level 2.</span>
        </span>
      </span>
    );
  }
}

ReactDOM.render(<Dialog/>, document.getElementById('View'));

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="View"></div>