//----------------------------------------------------------------
function InitSpringBox(a_id, b_id){
		document.getElementById(a_id).width_num=250;
		document.getElementById(b_id).width_num = 300 - document.getElementById(a_id).width_num;
		document.getElementById(a_id).style.width= document.getElementById(a_id).width_num + "px";
		document.getElementById(b_id).style.width= document.getElementById(b_id).width_num + "px";
}
//----------------------------------------------------------------
function springBox(a_id, b_id){
	if(document.getElementById(a_id).width_num == undefined ){
		document.getElementById(a_id).width_num=50;
		document.getElementById(b_id).width_num = 300 - document.getElementById(a_id).width_num;
	}
	my_id=a_id;
	u_id=b_id;
	//clearInterval(myTimer);
	myTimer1 = setInterval("expandBox()",10);
	myTimer2 = setInterval("shrinkBox()",10);
	//document.getElementById(a_id).style.width="250px";
	//document.getElementById(b_id).style.width="50px";
}
//----------------------------------------------------------------
function spring(){
	//alert(document.getElementById(my_id).width_num);
	
	
}

function expandBox(){
	if( 250 <= document.getElementById(my_id).width_num ){
		clearInterval(myTimer1);
	}
	else{
		document.getElementById(my_id).width_num +=10;	
		document.getElementById(my_id).style.width= document.getElementById(my_id).width_num + "px";
	}
}
function shrinkBox(){
	if( document.getElementById(u_id).width_num <= 50 ){
		clearInterval(myTimer2);
	}
	else{
		document.getElementById(u_id).width_num -=10;	
		document.getElementById(u_id).style.width= document.getElementById(u_id).width_num + "px";
	}
}