//Javascript Document
/*
Version: 1.0.0
Author: Lone
Date: 2010/4/26
*/

function DropDownList(){

var Items = [];
var current = null;

this.add = function(sId, sOpt, sClass){
   sId = this.$(sId);
   var pos = getPosition(sId);
   //alert(pos.posX + ', ' + pos.posY);
   var field = document.createElement('input');
   field.type = 'hidden';
   field.name = sId.id;
   field.value = '';
   sId.parentNode.insertBefore(field, null);
   var s = document.createElement('div');
   s.style.position = 'absolute';
   s.style.left = pos.posX + 'px';
   s.style.top = pos.posY + 'px';
   s.style.width = sId.offsetWidth + 'px';
   s.style.display = 'none';
   if (sClass && sClass!='')
   {
    s.className = sClass;
   }
   document.body.insertBefore(s, null);
   s.index = Items.length;
   sId.index = Items.length;
   Items.push(s);

   if (typeof(sOpt) == 'object')
   {
    var opts = document.createElement('ul');
   
    for ( var item in sOpt.Items )
    {
     var opt = document.createElement('li');
     opt.appendChild(document.createTextNode(sOpt.Items[item]));
     opt.value = item;
     opt.onmouseover = function(){
      this.className = 'on'; 
      this.title = (this.innerText) ? this.innerText : this.textContent; 
     }
     opt.onmouseout = function(){ this.className = ''; }
     opt.onclick = function(){
      s.style.display = 'none';
      sId.innerHTML = this.innerHTML;
      field.value = this.value;
     }

     opts.appendChild(opt);
    }
    s.appendChild(opts);
    if (sOpt.defaultValue && sOpt.defaultValue!='')
    {
     sId.innerHTML = sOpt.Items[sOpt.defaultValue] ? sOpt.Items[sOpt.defaultValue] : sOpt.defaultValue;
     field.value = sOpt.defaultValue;
    }
   }
  
   sId.onclick = function(){
    if (current != null && current!=this.index)Items[current].style.display = 'none';
    var s = Items[this.index];
    s.style.display = (s.style.display == 'none') ? '' : 'none';
    current = s.index;
   }
}

this.$ = function(el){
   if(!el) return null;
   if(typeof el=='string') return document.getElementById(el);
   if(typeof el=='object') return el;
   return null;
}

this.start = function(){
   var close = function(){
    if (current!=null && Items[current].style.display != 'none')
    {
     Items[current].style.display = 'none';
    }
   }
   if (document.attachEvent)
   {
    document.attachEvent('onmouseup', close);
   }else{
    document.addEventListener('mouseup', close, true);
   }
}

var getPosition = function(ddlOptions){
   var obj = ddlOptions;
   var x=obj.offsetLeft, y= obj.offsetHeight + obj.offsetTop;

   while(obj.offsetParent){
    x += obj.offsetParent.offsetLeft;
    y += obj.offsetParent.offsetTop;
    obj = obj.offsetParent;
   }

   obj = ddlOptions;

   while(obj.tagName != 'BODY'){
    if( obj["scrollLeft"]) x -= obj.scrollLeft;
    if( obj["scrollTop"]) x -= obj.scrollTop;
    obj = obj.parentNode;
   }

   x += getScrollLeft();
   y += getScrollTop();

   return { posX:x, posY:y }
}
}

function getScrollLeft() {
return filterResults (
   window.pageXOffset ? window.pageXOffset : 0,
   document.documentElement ? document.documentElement.scrollLeft : 0,
   document.body ? document.body.scrollLeft : 0
);
}
function getScrollTop() {
return filterResults (
   window.pageYOffset ? window.pageYOffset : 0,
   document.documentElement ? document.documentElement.scrollTop : 0,
   document.body ? document.body.scrollTop : 0
);
}
function filterResults(n_win, n_docel, n_body) {
var n_result = n_win ? n_win : 0;
if (n_docel && (!n_result || (n_result > n_docel)))
   n_result = n_docel;
return n_body && (!n_result || (n_result > n_body)) ? n_body : n_result;
}