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- 请高手帮忙看哈,一上面这段代码的意思
日期:2014-05-16 浏览次数:20347 次
请高手帮忙看哈,一下面这段代码的意思。
<script type="text/javascript">
var $ = function (id) {
return "string" == typeof id ? document.getElementById(id) : id;
};
var Class = {
create: function() {
return function() {
this.initialize.apply(this, arguments);
}
}
}
Object.extend = function(destination, source) {
for (var property in source) {
destination[property] = source[property];
}
return destination;
}
var TransformView = Class.create();
TransformView.prototype = {
//容器对象,滑动对象,切换参数,切换数量
initialize: function(container, slider, parameter, count, options) {
if(parameter <= 0 || count <= 0) return;
var oContainer = $(container), oSlider = $(slider), oThis = this;
this.Index = 0;//当前索引
this._timer = null;//定时器
this._slider = oSlider;//滑动对象
this._parameter = parameter;//切换参数
this._count = count || 0;//切换数量
this._target = 0;//目标参数
this.SetOptions(options);
this.Up = !!this.options.Up;
this.Step = Math.abs(this.options.Step);
this.Time = Math.abs(this.options.Time);
this.Auto = !!this.options.Auto;
this.Pause = Math.abs(this.options.Pause);
this.onStart = this.options.onStart;
this.onFinish = this.options.onFinish;
oContainer.style.overflow = "hidden";
oContainer.style.position = "relative";
oSlider.style.position = "absolute";
oSlider.style.top = oSlider.style.left = 0;
},
//设置默认属性
SetOptions: function(options) {
this.options = {//默认值
Up: true,//是否向上(否则向左)
Step: 5,//滑动变化率
Time: 10,//滑动延时
Auto: true,//是否自动转换
Pause: 2000,//停顿时间(Auto为true时有效)
onStart: function(){},//开始转换时执行
onFinish: function(){}//完成转换时执行
};
Object.extend(this.options, options || {});
},
//开始切换设置
Start: function() {
if(this.Index < 0){
this.Index = this._count - 1;
} else if (this.Index >= this._count){ this.Index = 0; }
this._target = -1 * this._parameter * this.Index;
this.onStart();
this.Move();
},
//移动
Move: function() {
clearTimeout(this._timer);
var oThis = this, style = this.Up ? "top" : "left", iNow = parseInt(this._slider.style[style]) || 0, iStep = this.GetStep(this._target, iNow);
if (iStep != 0) {
this._slider.style[style] = (iNow + iStep) + "px";
this._timer = setTimeout(function(){ oThis.Move(); }, this.Time);
} else {
this._slider.style[style] = this._target + "px";
this.onFinish();
if (this.Auto) { this._timer = setTimeout(function(){ oThis.Index++; oThis.Start(); }, this.Pause); }
}