Had a look at this example, which is quite interesting. If I understand correctly, it is a plugin which will change the behavior of all views.

2 more questions:

(1) Is it possible to derive a Canvas2D which will be used only by a specific class of Sequence (in my case for example, I work with a class derived from Sequence that I called “SequencePlus”). Where can I declare that SequencePlus is “associated” with my own class of Canvas2D?

(2) where is the best place to introduce a text label to define the size of a step to browse through a pile of images? Canvas2D? Viewer? I would like to adjust the interval between consecutive images. Right now, it is “1”, but I would like to change it to 3, 5, 10, 30, etc..