Making XUL Live
¥function addItem() {
¥  var listbox = document.getElementById("itemlist");
¥  var listitem = document.createElement("listitem");
¥  var labelfield = document.getElementById("labelfield");
¥  listbox.appendChild(listitem);
¥  listitem.label = labelfield.value;
¥  labelfield.value = "";
¥  validateInput();
¥  labelfield.focus();
¥}
¥
¥function validateInput() {
¥  var field = document.getElementById("labelfield");
¥  var button = document.getElementById("addButton");
¥  button.disabled = field.value == "";
¥}