Notification.requestPermission() - Web APIs 编辑

Note:

This feature is available in Web Workers.

Secure context

This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Note: This feature is not available in SharedWorker

Note: Safari still uses the callback syntax to get the permission. Read Using the Notifications API for a good example of how to feature detect this and run code as appropriate.

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
  • default

Examples

Assume this basic HTML:

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

It's possible to send a notification as follows — here we present a fairly verbose and complete set of code you could use if you wanted to first check whether notifications are supported, then check if permission has been granted for the current origin to send notifications, then request permission if required, before then sending a notification.

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 whether notification permissions have already been granted
  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().then(function (permission) {
      // If the user accepts, let's create a notification
      if (permission === "granted") {
        var notification = new Notification("Hi there!");
      }
    });
  }

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

We no longer show a live sample on this page, as Chrome and Firefox no longer allow notification permissions to be requested from cross-origin <iframe>s, with other browsers to follow. To see a example in action, check out our To-do list example (also see the app running live.)

Note: In the above example we spawn notifications in response to a user gesture (clicking a button). This is not only best practice — you should not be spamming users with notifications they didn't agree to — but going forward browsers will explicitly disallow notifications not triggered in response to a user gesture. Firefox is already doing this from version 72, for example.

Specifications

SpecificationStatusComment
Notifications APILiving StandardLiving standard

Browser compatibility

BCD tables only load in the browser

See also

如果你对这篇内容有疑问,欢迎到本站社区发帖提问 参与讨论,获取更多帮助,或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论, 你可以免费 注册 一个本站的账号。
列表为空,暂无数据

词条统计

浏览:101 次

字数:5774

最后编辑:7年前

编辑次数:0 次

    我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站,即表示您同意使用 Cookies 和您的相关数据。
    原文