html5 desktop notifications (Web Notifications) are very useful when it is necessary to have desktop notification effects when new messages come online. Here is a brief introduction to this new attribute of html5.
Here is a good demo: html5 web notification demo
From the demo above we can get the basic core code we need, as follows:
<script><br> var Notification = window. Notification || window.mozNotification || window.webkitNotification;<br> <br> Notification.requestPermission(function (permission) {<br> // console.log(permission);<br> });<br> <br> function show() {<br> var instance = new Notification(<br> "test title", {<br> body: " test message"<br> }<br> );<br> <br> instance. onclick = function () {<br> // Something to do<br> };<br> instance.onerror = function () {<br> // Something to do<br> };<br> instance.onshow = function () {<br> // Something to do<br> };<br> instance.onclose = function () {<br> // Something to do<br> };<br> <br> return false; <br> }<br></script>
Among them:
Notification.requestPermission The function of this code is to request permission from the user .
Through the above examples, we already have the basic idea. When loading the document first, we ask the user for permission. After obtaining the permission, it will be so easy in the future.
window.addEventListener('load', function () {
// At first, let's check if we have permission for notification
if (Notification && Notification.permission !== "granted") {
Notification.requestPermission(function (status) {
if (Notification.permission !== status) {
Notification.permission = status;
}
});
}
});
The verification passed under Firefox, but it always failed to come out under Chrome. Later I found this paragraph
Not a Bug, Feature.
Desktop Notifications can only be triggered via a user action. Typing into the
JavaScript console has the same effect as raw javascript code embedded into the web
page (no user action). Typing the javascript into the location bar, however ,
represents a user-action (the user is intentionally visiting a javascript link to
enable notifications, probably for sites that tend to use href="javascript：" instead
of onclick="".
I'm pretty sure this is a non-issue.
It turns out that must be manually triggered by the user under chrome, otherwise, the chrome browser will ignore this js
But it is certainly impossible to add a button or hyperlink to our website to explicitly allow users to authorize it. Well, actually this is not a problem. We can handle this on the buttons that users often click. Just authorize it. Under Chrome, one authorization is valid for life. Unless you go into settings and ban him.
To put it together, the code is as follows:
function showMsgNotification(title, msg){
var Notification = window.Notification || window.mozNotification || window.webkitNotification;
if (Notification && Notification.permission === "granted") {
var instance = new Notification(
title, {
body: msg,
icon: "image_url"
}
);
instance.onclick = function () {
// Something to do
};
instance.onerror = function () {
// Something to do
};
instance.onshow = function () {
// Something to do
// console.log(instance.close);
setTimeout(instance.close, 3000);
};
instance.onclose = function () {
// Something to do
};
}else if (Notification && Notification.permission !== "denied") {
Notification.requestPermission(function (status) {
if (Notification.permission !== status) {
Notification.permission = status;
}
// If the user said okay
if (status === "granted") {
var instance = new Notification(
title, {
body: msg,
icon: "image_url"
}
);
instance.onclick = function () {
// Something to do
};
instance.onerror = function () {
// Something to do
};
instance.onshow = function () {
// Something to do
setTimeout(instance.close, 3000);
};
instance.onclose = function () {
// Something to do
};
}else {
return false
}
});
}else{
return false;
}
}
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
