Anything that inherits from UIComponent will implement
Additionally UIMovieClip also implements this. You also have
the choice of
extending, say, Sprite, and adding on the additional
properties and methods
necessary to implement the interface.
All containers (Canvas, Box, VBox, HBox) inherit from
UIComponent and so
will implement this interface. However, a container cannot
accept as a
child anything that does NOT implement this interface
DisplayObject, and I think TextField and maybe a few more).