I've tried GridLayout, but haven't succeeded in making it do what I want.
I have 2 Composites. I'd like one to be at the left, and the other to be at the right, both re-sizing width as needed depending on their contents.
I'm currently trying FormLayout. I think I have it working correctly, though the WindowBuilder GUI is being confusing.
When I click on one of the Composites that is in the form, all the alignment buttons show up on the tool bar - and ALL of them are disabled.
If I right-click on the composite, I can use the "Quick Constraints" popup menu, and those seem to work.
The documentation talks about a "Floating Layout Assistant" - which I have been unable to find.