Mouse event delay switching plug-in_javascript skills

原理很简单：
onmouseover、onmouseout执行业务代码时使用setTimeout进行延时，第二次触发的时候先清除掉前面的setTimeout。
原理

复制代码 代码如下:

var timer;
document.getElementById('test').onmouseover = function () {
clearTimeout(timer);
timer = setTimeout(function () {
alert('over')
}, 150);
};
document.getElementById('test').onmouseout = function () {
clearTimeout(timer);
timer = setTimeout(function () {
alert('out')
}, 150);
};

上述代码可以看到，定时器返回值(唯一ID)由timer保存着，onmouseover与onmouserout都可以清除未执行的定时器，防止重复执行。这里timer让onmouseover与onmouserout有了一个“组”的概念，我们还可以让更多的元素能够访问到“组”，例如插入式的下拉菜单与tips等触发元素与弹出层都需要共用同一个timer，这样不会因为鼠标离开导致层被关闭（只要指针还在层上）。
封装事件

复制代码 代码如下:

/*!
* hoverDelay.js
* http://www.planeArt.cn
* Copyright 2011, TangBin
* Dual licensed under the MIT or GPL Version 2 licenses.
*/
(function (pluginName) {
var id = 0, data = {},
addEvent = function (elem, type, callback) {
if (elem.addEventListener) {
elem.addEventListener(type, callback, false);
} else {
elem.attachEvent('on' + type, function () {callback.call(elem)});
};
};
this[pluginName] = function (elem, over, out, group, speed) {
id ++;
if (arguments.length === 0) return id;
if (typeof arguments[1] !== 'function') return clearTimeout(data[arguments[1]]);
if (typeof elem === 'string') elem = document.getElementById(elem);
group = group || elem[pluginName] || id;
speed = speed || 150;
elem[pluginName] = group;
addEvent(elem, 'mouseover', function () {
var elem = this,
fn = function () {over.call(elem)};
clearTimeout(data[group]);
data[group] = setTimeout(fn, speed);
});
addEvent(elem, 'mouseout', function () {
var elem = this,
fn = function () {out.call(elem)};
clearTimeout(data[group]);
data[group] = setTimeout(fn, speed);
});
};
})('hoverDelay');

data负责保存着自定义的“组”，同一“组”下甚至可以暂停mouseout的回调函数执行，这样可以实现套嵌操作。

接口说明

方法	参数	作用
hoverDelay (elem, over, out, group)	元素, 鼠标靠近时回调函数, 鼠标离开时回调函数, 设置延时分组名称[可选]	设置延时触发效果
hoverDelay (elem, group)	元素, 延时分组名称	停止鼠标离开执行的回调函数
hoverDelay ()	[无]	获取唯一延时分组名称

Updated on 2011-01-22
I noticed the description of the hover event in the jQuery API:
will be accompanied by a detection of whether the mouse is still in a specific element (for example, image in a div), if so, it will continue to remain in the "hover" state without triggering the move-out event (fixes a common mistake in using the mouseout event).
Is there a bug in mouseout? This reminds me that when I was working on a mouse-triggered display business card (similar to Tencent Weibo's avatar business card), the mouseout event was often executed incorrectly. So I checked how jQuery's hover source code solves this problem, and found that it uses "mouseenter" and "mouseleave" instead of "mouseover" and "mouseout". "mouseenter" and "mouseleave" are IE (6, 7, 8 ) unique events are not supported by standard browsers and need to be simulated. The final version:

Copy code The code is as follows:

/*!
* hoverDelay.js v1.1
* http://www.planeArt.cn
* Copyright 2011, TangBin
* Dual licensed under the MIT or GPL Version 2 licenses.
*/
(function (pluginName) {
var id = 0, data = {},
addEvent = function (elem, type, callback) {
if (elem.addEventListener) {
if (type === 'mouseenter') {
elem.addEventListener('mouseover', withinElement(callback), false);
} else if (type = == 'mouseleave') {
elem.addEventListener('mouseout', withinElement(callback), false);
} else {
elem.addEventListener(type, callback, false);
} ;
} else {
elem.attachEvent('on' type, function () {callback.call(elem, window.event)});
};
},
withinElement = function(callback) {
return function (event) {
var parent = event.relatedTarget;
try {
while (parent && parent !== this) parent = parent.parentNode;
if (parent !== this) callback.apply(this, arguments);
} catch(e) {};
};
};
this[pluginName] = function ( elem, over, out, group, speed) {
id ;
if (arguments.length === 0) return id;
if (typeof arguments[1] !== 'function') return clearTimeout(data[arguments[1]]);
if (typeof elem === 'string') elem = document.getElementById(elem);
group = group || elem[pluginName] || id;
speed = speed || 150;
elem[pluginName] = group;
addEvent(elem, 'mouseenter', function () {
var elem = this,
fn = function ( ) {over.call(elem)};
clearTimeout(data[group]);
data[group] = setTimeout(fn, speed);
});
addEvent(elem, ' mouseleave', function () {
var elem = this,
fn = function () {out.call(elem)};
clearTimeout(data[group]);
data[group] = setTimeout(fn, speed);
});
};
})('hoverDelay');

View version 1.1 demo
http ://demo.jb51.net/js/2011/hover/index.htm
New window opens

Download

1, Native version 1.1
2. jQuery plug-in version