I understand to draw on a Composite, you can add a paint listener, but that results in drawing under the children. What if I want to draw over the top of children?
T
Unfortunately this is not an implemented feature, as you can see in Bug#114749.
You'd have to code your own custom solution (e.g, calculation the drawing area for each affected composite and then draw on each).
Its quite an old bug, but upvoting is always a good idea if you think this is a "must have".