Handling User Input

Managing clicks

The next step is to manage clicks on the start and stop buttons. First, grab the elements off the page with querySelector:

let startButton = document.querySelector('#start-button');
let stopButton = document.querySelector('#stop-button');

Tracking click events

Now that we have buttons, we need to figure out when the user clicks them. You could use the constructor covered in the last section to build an observable that streams click events from an arbitrary element: