如何使用拉取通知显示桌面警报？答案

【问题标题】：How can I show desktop alert using pull notification?如何使用拉取通知显示桌面警报？
【发布时间】：2019-02-06 18:26:39
【问题描述】：

当浏览器关闭或打开时，如何显示来自 chrome、firefox 或 IE 的桌面通知？有没有办法使用拉取通知方法来做到这一点？

【问题讨论】：

标签： google-chrome internet-explorer firefox notifications microsoft-edge

【解决方案1】：

您可以尝试检查通知 API。

通知 API 允许网页控制向最终用户显示系统通知。这些在顶级浏览上下文视口之外，因此即使用户切换选项卡或移动到不同的应用程序也可以显示。该 API 旨在与跨不同平台的现有通知系统兼容。

示例代码：

<!doctype html>
<head>
<script>
window.addEventListener('load', function () {
  // At first, let's check if we have permission for notification
  // If not, let's ask for it
  if (window.Notification && Notification.permission !== "granted") {
    Notification.requestPermission(function (status) {
      if (Notification.permission !== status) {
        Notification.permission = status;
      }
    });
  }

  var button = document.getElementsByTagName('button')[0];

  button.addEventListener('click', function () {
    // If the user agreed to get notified
    // Let's try to send ten notifications
    if (window.Notification && Notification.permission === "granted") {
      var i = 0;
      // Using an interval cause some browsers (including Firefox) are blocking notifications if there are too much in a certain time.
      var interval = window.setInterval(function () {
        // Thanks to the tag, we should only see the "Hi! 9" notification 
        var n = new Notification("Hi! " + i, {tag: 'soManyNotification'});
        if (i++ == 9) {
          window.clearInterval(interval);
        }
      }, 200);
    }

    // If the user hasn't told if he wants to be notified or not
    // Note: because of Chrome, we are not sure the permission property
    // is set, therefore it's unsafe to check for the "default" value.
    else if (window.Notification && Notification.permission !== "denied") {
      Notification.requestPermission(function (status) {
        // If the user said okay
        if (status === "granted") {
          var i = 0;
          // Using an interval cause some browsers (including Firefox) are blocking notifications if there are too much in a certain time.
          var interval = window.setInterval(function () {
            // Thanks to the tag, we should only see the "Hi! 9" notification 
            var n = new Notification("Hi! " + i, {tag: 'soManyNotification'});
            if (i++ == 9) {
              window.clearInterval(interval);
            }
          }, 200);
        }

        // Otherwise, we can fallback to a regular modal alert
        else {
          alert("Hi!");
        }
      });
    }

    // If the user refuses to get notified
    else {
      // We can fallback to a regular modal alert
      alert("Hi!");
    }
  });
});
</script>
</head>
<body>
<button>Notify me!</button>
</body>
</html>

参考资料：

(1)Notifications API

(2)Using the Notifications API

【讨论】：