javascript oop开发滑动(slide)菜单控件_javascript技巧

var $sliding = document.getElementById("silding");
var s1 = new Sliding();
s1.commands = $sliding.getElementsByTagName("dt");
s1.panels = $sliding.getElementsByTagName("dd"); ;
s1.init("mouseover", "active");

function Slider(i, panelHeight) { //dto
this.index = i;
this.panelHeight = panelHeight;
}
//class Sliding {
function Sliding(activeIndex) {
this.commands = [];
this.panels = [];
this.activeIndex = activeIndex || 0;
this.sliderCache = {};
}
Sliding.prototype = {
//绑定事件
init: function(eventName, activeCssClass) {
var _this = this;
var cmds = _this.commands;
_this.activeClass = activeCssClass;
for (var i = 0, n = cmds.length; i cmds[i]["on" + eventName] = function(e) {
_this.handel(this, e);
}
cmds[i].index = i;
if (i == _this.activeIndex) {
_this.sliderCache = new Slider(i, _this.panels[i].offsetHeight);
}
}
},
//事件处理函数
handel: function(elem, args) {
var _this = this;
var index = elem.index;
var cacheIndex = _this.sliderCache.index;
var cacheElem = _this.commands[cacheIndex];
if (index == cacheIndex) return;
var showPanel = _this.panels[index];
var hidePanel = _this.panels[cacheIndex];
var h = parseInt(_this.sliderCache.panelHeight);
showPanel.style.height = "0px";
showPanel.style.display = "block";
_this.tween(hidePanel, showPanel, h);
elem.className = _this.activeClass;
cacheElem.className = cacheElem.className.replace(eval("/ ?"+_this.activeClass+" ?/"),"");
_this.sliderCache = new Slider(index, h);
},
//动画算法
tween: function(obj0, obj1, h) {
_this = arguments.callee;
var step = 20;
if ("\v" == "v") {
step = 30;
}
if (h > 0) {
var h0 = obj0.offsetHeight;
var h1 = obj1.offsetHeight;
if (h obj0.style.display = "none";
obj0.style.height = (h1 + h) + "px";
obj1.style.height = (h1 + h) + "px";
} else {
h = h - step;
obj0.style.height = (h0 - step) + "px";
obj1.style.height = (h1 + step) + "px";
setTimeout(function() {
_this(obj0, obj1, h)
},
50)
}
}
}
}
//}