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The requestPermission()
method of the Notification
interface requests permission from the user for the current origin to display notifications.
Syntax
The latest spec has updated this method to a promise-based syntax that works like this:
Notification.requestPermission().then(function(permission) { ... });
Previously, the syntax was based on a simple callback; this version is now deprecated:
Notification.requestPermission(callback);
Parameters
callback
Optional Deprecated since Gecko 46- An optional callback function that is called with the permission value. Deprecated in favor of the promise return value.
Returns
A Promise
that resolves to a DOMString
with the permission picked by the user. Possible values for this string are granted
, denied
, or default
.
Example
The following snippet requests permission from the user, then logs a different result to the console depending on the users' choice.
Notification.requestPermission().then(function(result) { if (result === 'denied') { console.log('Permission wasn\'t granted. Allow a retry.'); return; } if (result === 'default') { console.log('The permission request was dismissed.'); return; } // Do something with the granted permission. });
Specifications
Specification | Status | Comment |
---|---|---|
Notifications API | Living Standard | Living standard |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 5webkit[1] 22 |
4.0 (2.0)moz[2] 22.0 (22.0) |
No support | 25 | 6[3] |
promise-based version | 46.0 | 47.0 (47.0) | ? | 40 | No support |
Feature | Android | Android Webview | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|---|
Basic support | ? | (Yes) | 4.0 (2.0)moz[2] 22.0 (22.0) |
1.0.1moz[2] 1.2 |
No support | ? | No support | (Yes) |
promise-based version | ? | ? | 47.0 (47.0) | ? | ? | ? | ? | ? |
[1] Before Chrome 22, the support for notification followed an old prefixed version of the specification and used the navigator.webkitNotifications
object to instantiate a new notification.
Before Chrome 32, Notification.permission
was not supported.
Before Chrome 42, service worker additions were not supported.
[2] 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 supported only the click
and close
events.
Nick Desaulniers wrote 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 without the icon, then the icon is fetched, but it works on all versions of Firefox OS.
When using notifications in a Firefox OS 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": {} }
[3] Safari started to support notification with Safari 6, but only on Mac OSX 10.8+ (Mountain Lion).