15. An apparatus, comprising: a storage device that stores instructions; and a processor coupled to the storage device and being operative with the instructions to: initialize, based on a captured event at a user interface, an event object including an event type that describes a user interface action; provide the initialized event object to an object model, the object model comprising user interface gadgets organized in a hierarchy, the user interface gadgets including a first user interface gadget including a first event listener that listens for a first trigger event condition to perform a first action on the first user interface gadget; recursively propagate the event object through the user interface gadgets based on the hierarchy of the user interface gadgets; and initiate, by the first event listener and responsive to determining that the propagated event fulfills the first trigger event condition, the first action on the first user interface gadget for display to a user.
15. An apparatus, comprising: a storage device that stores instructions; and a processor coupled to the storage device and being operative with the instructions to: initialize, based on a captured event at a user interface, an event object including an event type that describes a user interface action; provide the initialized event object to an object model, the object model comprising user interface gadgets organized in a hierarchy, the user interface gadgets including a first user interface gadget including a first event listener that listens for a first trigger event condition to perform a first action on the first user interface gadget; recursively propagate the event object through the user interface gadgets based on the hierarchy of the user interface gadgets; and initiate, by the first event listener and responsive to determining that the propagated event fulfills the first trigger event condition, the first action on the first user interface gadget for display to a user. 17. The apparatus of claim 15 , wherein the first user interface gadget contains a reference to a respective behavior definition that defines the first trigger event condition and a script to perform the first action on the first user interface gadget.