chrome.notifications.update() or create()

Question

I want my chrome extension to take a notification.id, and:

1. Update an existing notification if it does exist. OR
2. Create a new notification

Answer 1

Edit: This approach no longer works on any platform except ChromeOS due to the removal of Chrome's Notification Center.

Possible ideas to work around it include using requireInteraction: true flag on notifications to fully control notification lifetime.

---

There is a dirty trick for re-showing a notification. If you change a notification's priority to a higher value, it will be re-shown if it exists.

function createOrUpdate(id, options, callback) {
  // Try to lower priority to minimal "shown" priority
  chrome.notifications.update(id, {priority: 0}, function(existed) {
    if(existed) {
      var targetPriority = options.priority || 0;
      options.priority = 1;
      // Update with higher priority
      chrome.notifications.update(id, options, function() {
        chrome.notifications.update(id, {priority: targetPriority}, function() {
          callback(true); // Updated
        });
      });
    } else {
      chrome.notifications.create(id, options, function() {
        callback(false); // Created
      });
    }
  });
}

Answer 2

Xan's answer no longer works on Windows, MacOS, or Linux. At this point the only way to make sure your notification displays, no matter what, is to create a new notification.

If you want to prevent multiple notifications from being on screen, you'll have to clear the old notification and replace it with a new one. This is demonstrated below.

NOTIFICATION_ID = "some_random_string";
function showNotification ( ... , callback) {
    chrome.notifications.clear(NOTIFICATION_ID, function(cleared) {
        var options = {
            // whatever
        };
        chrome.notifications.create(NOTIFICATION_ID, options, callback);
    });
}

Of course, this results in an animation of existing notification getting dismissed and a new notification immediately taking its place, but unfortunately this is unavoidable.