An event is generated when an action is fired on diputree.
start, stop, load, unload, click, dblclick, mouseover, mouseout and keypress
var event = diputree.lookup("#/1","#xpointer(hasevent/*)");
var eventName = "none";
if ( event!="" ) {
eventName = diputree.getName(event);
}
alert ("event " + eventName + " occurred.");