See section 
for information about the role of administrators.
The wx:media-admin% class is never instantiated directly. It
is not event instantiated through derived class by most programmers;
each wx:media-canvas% and wx:media-snip% object
creates its own administrator. However, it may be useful to derive a
new instance of this class to display buffers in a new context. Also,
it may be usefull to call the methods of an existing administrator
from an owned buffer.
To create a new wx:media-admin% class, all methods described here must be overridden. They are all invoked by the administrator's buffer.
Creates an empty object.