function checkaddcart(id,chk,flag){
	//alert($(id).getElementsByTagName('input').length);
   
	if(flag == '1'){
		$('cart_quantity').submit();
	}
	else{
		var state  = 0;
		var $input = $(id).getElementsByTagName('input');
	
		var num    = $input.length;		
		
		for (var i=0; i < num; i++){
	    	if ($input[i].name == chk){
	    			if($input[i].checked)
	    				flag++;
	    	}
	    	if($input[i].name == 'quantity[]'){
	     		if(parseInt($input[i].value) > 0)
	    			 state++;
	    	}
		}
	
		if(!flag && !state)
			alert("Please choose one size at least!");
	   else
	   $('cart_quantity').submit();
	}
	
}

function change_products(action,key,flag){
	
	quantity = parseInt($('quantity_'+key).value);
	if(!quantity)
		quantity = 0;
	if(action=='add'){
		if(flag)
			$('quantity_'+key).value = quantity;
		else
			$('quantity_'+key).value = quantity+1;
		
	}
	else if(action=='dec'){
		
		if(quantity > 0)
			$('quantity_'+key).value = quantity-1;
	}		
	
	if(parseInt($('quantity_'+key).value)>0)
		$('id_'+key).checked = true;
	else
		$('id_'+key).checked = false;
	
}
function change_position(action,style,flag){
	if(action == 'add'){
		if(flag == 1)
			style.style.backgroundPosition = '0 -20px';
		else
			style.style.backgroundPosition = '0 0';
	}
	else{
		
		if(flag == 1)
			style.style.backgroundPosition = '0 -30px';
		else
			style.style.backgroundPosition = '0 -10px';		
	}
	
}