Notification

Summary

The Notification object is used to configure and display desktop notifications to the user.

Constructor

var notification = new Notification(title, options)

Parameters

title

The title that must be shown within the notification

options Optional

An object that allows to configure the notification. It can have the following properties:

• dir : The direction of the notification; it can be auto, ltr, or rtl
• lang: Specify the lang used within the notification. This string must be a valid BCP 47 language tag.
• body: A string representing an extra content to display within the notification
• tag: An ID for a given notification that allows to retrieve, replace or remove it if necessary
• icon: The URL of an image to be used as an icon by the notification

Properties

Static properties

Those properties are available only on the Notification object itself.

Notification.permission Read only

A string representing the current permission to display notifications. Possible value are: denied (the user refuses to have notifications displayed), granted (the user accepts to have notifications displayed), or default (the user choice is unknown and therefore the browser will act as if the value was denied).

Instance properties

Those properties are available only on instances of the Notification object.

Notification.title Read only (moz only)

The title specified when the constructor was invoked.

Notification.dir Read only

The direction used by the notification as defined within the constructor options.

Notification.lang Read only

The code lang used by the notification as defined within the constructor options.

Notification.body Read only

The body string used by the notification as defined within the constructor options.

Notification.tag Read only

The id of the notification (if any) as defined within the constructor options.

Notification.icon Read only

The URL of the image used as an icon as defined within the constructor options.

Event handlers

Notification.onclick

A handler for the click event. It is triggered each time the user clicks on the notification.

Notification.onshow

A handler for the show event. It is triggered when the notification is displayed.

Notification.onerror

A handler for the error event. It is triggered each time the notification encounters an error.

Notification.onclose

A handler for the close event. It is triggered when the user closes the notification.

Methods

Static methods

Those methods are available only on the Notification object itself.

Notification.requestPermission()

This method is used to ask the user for permission for the page to display notifications. This method must be called as the result of a user action (eg: onclick callback), and cannot be used without it.

Instance methods

Those properties are available only on an instance of the Notification object or through its prototype.

Notification.close()

This method allows to programmatically close a notification.

The Notification objects also inherit from the EventTarget interface.

EventTarget.addEventListener()

Register an event handler of a specific event type on the EventTarget.

EventTarget.removeEventListener()

Removes an event listener from the EventTarget.

EventTarget.dispatchEvent()

Dispatch an event to this EventTarget.

Example

Assume this basic HTML:

<button onclick="notifyMe()">Notify me!</button>

It's possible to send a notification as follows:

function notifyMe() {
  // Let's check if the browser supports notifications
  if (!("Notification" in window)) {
    alert("This browser does not support desktop notification");
  }

  // Let's check if the user is okay to get some notification
  else if (Notification.permission === "granted") {
    // If it's okay let's create a notification
    var notification = new Notification("Hi there!");
  }

  // Otherwise, we need to ask the user for permission
  else if (Notification.permission !== 'denied') {
    Notification.requestPermission(function (permission) {
      // If the user is okay, let's create a notification
      if (permission === "granted") {
        var notification = new Notification("Hi there!");
      }
    });
  }

  // At last, if the user already denied any notification, and you 
  // want to be respectful there is no need to bother them any more.
}

See the live result

Specifications

Permissions

When using notifications  in an open web app, be sure to add the desktop-notification permission in your manifest file. Notifications can be used at any permission level, hosted or above.

"permissions": {
    "desktop-notification":{}
}

Browser compatibility

Gecko notes

• Prior to Firefox 22 (Firefox OS <1.2), the instantiation of a new notification must be done with the navigator.mozNotification object through its createNotification method.
• Prior to Firefox 22 (Firefox OS <1.2), the Notification was displayed when calling the show method and was supporting the click and close events only.
• Nick Desaulniers has written a Notification shim to cover both newer and older implementations.
• One particular Firefox OS issue is that you can pass a path to an icon to use in the notification, but if the app is packaged you cannot use a relative path like /my_icon.png. You also can't use window.location.origin + "/my_icon.png" because window.location.origin is null in packaged apps. The manifest origin field fixes this, but it is only available in Firefox OS 1.1+. A potential solution for supporting Firefox OS <1.1 is to pass an absolute URL to an externally hosted version of the icon. This is less than ideal as the notification is displayed immediately with the icon missing, then the icon is fetched, but it works on all versions of Firefox OS.

Chrome notes

• Prior to Chrome 22, the support for notification was following an old prefixed version of the specification and was using the navigator.webkitNotifications object to instantiate a new notification.
• Prior to Chrome 32, Notification.permission was not supported.

Safari notes

• Safari started supporting notification with Safari 6 but only on Mac OSX 10.8+ (Mountain Lion).

See also

• Using Web Notifications