//-- getelementbyid wrapper
function $(_id) {
    if (document.getElementById) return document.getElementById(_id);
    if (document.all)            return document.all[_id];
    return false;
}

//-- toggle element display
function toggle(_id) {
    
    obj = $(_id);
    
    if (obj.style.display == "block") {
        obj.style.display = "none";
    } else {
        obj.style.display = "block";
    }
}
    
// onload event coupler
function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') { 
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}


function show() {
	var args = show.arguments;
	for(var i = 0; i < args.length; i++) {
		var el = document.getElementById(args[i]);
		if(el) {
			el.style.display = "block";
		}
	}
}

function hide() {
	var args = hide.arguments;
	for(var i = 0; i < args.length; i++) {
		var el = document.getElementById(args[i]);
		if(el) {
			el.style.display = "none";
		}
	}
}

function changeElementHeight(id,height) {
	var obj = document.getElementById(id);
	if(obj) {
		obj.style.height = height + "px";
	}
}