MACROMEDIA FLEX-FLEX ACTIONSCRIPT LANGUAGE Reference page 523

Example
The following example determines over what type of object the context menu was invoked:
my_cm = new ContextMenu();
function menuHandler(obj:Object, menu:ContextMenu) {
if(obj instanceof MovieClip) {
trace("Movie clip: " + obj);
}
if(obj instanceof TextField) {
trace("Text field: " + obj);
}
if(obj instanceof Button) {
trace("Button: " + obj);
}
}
my_cm.onSelect = menuHandler;
my_mc.menu = my_cm;
my_btn.menu = my_cm;
ContextMenu.onSelect 523