This is the abstract superclass for views in the PNGWalk tool. Concrete subclasses will do the work of actually laying out a particular view and handling events on it.
return the component that will generate mouse events. Some components have a JScrollPane, so simply adding a listener to the PngWalkView doesn't work. The base class implementation of this simply returns the PngWalkView, but such components should override this method.
return the mouse wheel listener, which should be added to each panel so the sequence position is easily adjusted.
Respond to property changes on the {@list WalkImageSequence} this view
represents. The default implementation just calls repaint(),
(or sequencChanged() if appropriate) but subclasses may override.