Example
The following example creates a selectable text field that constantly updates with the current date and time.
this.createTextField("date_txt", this.getNextHighestDepth(), 10, 10, 100, 22);
date_txt.autoSize = true;
date_txt.selectable = true;
var date_interval:Number = setInterval(updateTime, 500, date_txt);
function updateTime(my_txt:TextField) {
my_txt.text = new Date().toString();
}