function DomContainer()
{/* Dom Container keep html elements refrenced by dom ids.
    it's capable of selecting on of elements , and change attributes of the selected element
    (ex. changing background..)

*/
    this.objs=new Array();
    this.dependent_objs=Array();
    this.set_on_select=Array(); /*array of arrays*/
    this.set_on_unselect=Array(); /*array of arrays*/
    this.__selected="";
    this.disable_unselected=false;
    
    this.__addObj=__addObj;
    this.addByID=addByID;
    this.setOnSelect=setOnSelect;
    this.setOnUnSelect=setOnUnSelect;
    this.__getObjByID=__getObjByID;
    this.__setSelectedAttrs=__setSelectedAttrs;
    this.__setSelectedAttr=__setSelectedAttr;
    this.__setUnselectedsAttrs=__setUnselectedsAttrs;
    this.__setUnselectedAttr=__setUnselectedAttr;
    this.__addDependents=__addDependents;

}
DomContainer.prototype.setAttribute=function(obj, attr_name, attr_value)
    {
		if(obj)
		{
			if (obj.setStyle)
			{
				obj.setStyle(new String(attr_name), attr_value);
			}
			else if (obj.style)
			{
				obj.style[attr_name] = attr_value;
			}
		}
    }

DomContainer.prototype.disable=function(obj,disable_status)
    {
		if(obj && obj.disabled!=undefined)
			obj.disabled=disable_status;
    }
    
    function __addObj(obj)
    {
    	this.objs.push(obj);
    }

    function addByID(dom_id,dependent_ids)
    {/*add a new element with id "dom_id"
       dependent_ids is array of id's that will be selected when dom_id is selected too 
    */
		obj = document.getElementById(dom_id);
		if(!obj)
		{
		    alert("Element with id " + dom_id + " Not found");
		    return null;
		}
		this.__addObj(obj);
		this.__addDependents(dependent_ids);
	
    }

    function __addDependents(dependent_ids)
    {
    	dep_objs=new Array();
    	for (dep_index in dependent_ids)
    		dep_objs.push(document.getElementById(dependent_ids[dep_index]));
    	
        this.dependent_objs.push(dep_objs);
    }
    function setOnSelect(attr_name,attr_value)
    {/*
	add a new attribute to set when element is selected
    */
	this.set_on_select.push(new Array(attr_name,attr_value));
    }

    function setOnUnSelect(attr_name,attr_value)
    {/*
	add a new attribute to set when element is unselected
    */
	this.set_on_unselect.push(new Array(attr_name,attr_value));
    }
    
    
    DomContainer.prototype.toggle=function(id)
    {/*toggle of element, useful for on/off situations*/
	if(this.__selected==id)
	    this.select("dummy_id");
	else
	    this.select(id);
    }
    
    DomContainer.prototype.select=function(id)
    {/* select of elements */
		this.__selected=id;
		this.__setSelectedAttrs(id);
		this.__setUnselectedsAttrs(id);
    }
    
    function __getObjByID(id)
    {
	for (obj_index in this.objs)
	{
	    if (this.objs[obj_index].id == id)
		return new Array(this.objs[obj_index],this.dependent_objs[obj_index]);
	}
	return null;
    }
    
    function __setSelectedAttrs(id)
    {
		arr=this.__getObjByID(id);
		if(!arr)
		    return;
		
		obj=arr[0];
		dependents=arr[1];
		this.__setSelectedAttr(obj);
		for (dep_index in dependents)
		    this.__setSelectedAttr(dependents[dep_index]);
    }


    function __setSelectedAttr(obj)
    {
		for (attr_index in this.set_on_select)
		{
		    attr_name=this.set_on_select[attr_index][0];
		    attr_value=this.set_on_select[attr_index][1];
		    this.setAttribute(obj,attr_name,attr_value);
		}
	
		if(this.disable_unselected)
		    this.disable(obj,false);
	
    }
    
    function __setUnselectedsAttrs(id)
    {
    	for (obj_index in this.objs)
    	{	
		    if (this.objs[obj_index].id == id)
		    	continue;
	
		    obj=this.objs[obj_index];
		    this.__setUnselectedAttr(obj);
		    
		    
		    for (dep_index in this.dependent_objs[obj_index])
		    {
		    	this.__setUnselectedAttr(this.dependent_objs[obj_index][dep_index]);
		    }
    	}
    }

    function __setUnselectedAttr(obj)
    {
        for (attr_index in this.set_on_unselect)
        {
    	    attr_name=this.set_on_unselect[attr_index][0];
    	    attr_value=this.set_on_unselect[attr_index][1];
    	    this.setAttribute(obj,attr_name,attr_value);
        }

        if(this.disable_unselected)
        	this.disable(obj,true);

    }