function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}
function swapImg(id,src){
	if(!document.getElementById(id))return false;
	image = document.getElementById(id);
	image.setAttribute("src",src);
}