How to redraw a list in smalltalk

I have a List in my smalltalk application that gets updated by user events. The list updates correctly, but it on开发者_如何学编程ly redraws, repaints, or refreshes whenever the window is forced to redraw. So it'll appear as it is supposed to, but only when I hide and then reshow the window, or drag it off screen and then bring it back on.

How do I make the App window automatically redraw, whenever the list is updated?

I got this working by including:

self changed: #objectInList

In the method of the objects being changed.