function showPic(whichpic) {
  	//alert(whichpic);
	if (!document.getElementById("placeholder")) return true;
	var source = whichpic.getAttribute("href");
	//alert(source);
	var placeholder = document.getElementById("placeholder");
	// alert(placeholder);
	placeholder.setAttribute("src",source);
	placeholder.setAttribute('attr', 'my new attribute value');
	// if (!document.getElementById("description")) return false;
	// if (whichpic.getAttribute("title")) {
	// 	var text = whichpic.getAttribute("title");
	// } else {
	// 	var text = "";
	// }
	// var description = document.getElementById("description");
	// if (description.firstChild.nodeType == 3) {
	// 	description.firstChild.nodeValue = text;
	// }
	return false;
}

function prepareGallery() {
  if (!document.getElementsByTagName) return false;
  if (!document.getElementById) return false;
  if (!document.getElementById("imagegallery")) return false;
  var gallery = document.getElementById("imagegallery");
  var links = gallery.getElementsByTagName("a");
	for ( var i=0; i < links.length; i++) {
		links[i].onclick = function() {
      return showPic(this);
	}
    links[i].onkeypress = links[i].onclick;
  }
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

addLoadEvent(prepareGallery);