This class provides a panel which can also contain wx:media-edit% objects as it's children. Instead of putting wx:media-edit% objects into wx:media-canvas% objects, if you put the wx:media-edit% object directly into the panel, the panel will two extra operations, split, and collapse.
Calls wx:panel%'s super-init.
If parent is an instance of mred:frame% or mred:dialog-box%, calls parent's insert-panel method on itself. Otherwise, it calls parent's add-child method on itself.