lifecycle.html


<!DOCTYPE html>
An image will appear here in 3 seconds (<a href="https://thenounproject.com/term/cat/6725/">cat.svg by Marco Hernandez</a>, <a href="https://thenounproject.com/term/stallion/568432">horse.svg by Carla Dias</a>):
<script>
navigator.serviceWorker.register('/sw.js').then(reg => {
  reg.installing; // the installing worker, or undefined
  reg.waiting; // the waiting worker, or undefined
  reg.active; // the active worker, or undefined

  reg.addEventListener('updatefound', () => {
    // A wild service worker has appeared in reg.installing!
    const newWorker = reg.installing;

    newWorker.state;
    // "installing" - the install event has fired, but not yet complete
    // "installed"  - install complete
    // "activating" - the activate event has fired, but not yet complete
    // "activated"  - fully active
    // "redundant"  - discarded. Either failed install, or it's been
    //                replaced by a newer version

    newWorker.addEventListener('statechange', () => {
      // newWorker.state has changed
    });
  });
});

navigator.serviceWorker.addEventListener('controllerchange', () => {
  // This fires when the service worker controlling this page
  // changes, eg a new worker has as skipped waiting and become
  // the new active worker. 
});

</script>