I'm a bit at the end of what GL and SWT can do for me now, so I decided to write a new component. My Problem is that I want to display and change data in a TreeTable (Tree with Columns)-fashioned way. The Tree hasn't necessarily just one row but a hierarchiy for each object. Via a Format-Class I can decide if my item has children and so on. It will support writeback to the underlying list via custom or a DefaultCell Editor. This also means that one can change data in a (for example on the content of a collapsed) node, and the Format Class allows it to be saveback correctly.
It also has rudimentary Drag'n'Drop Support.
Since I want to keep my stuff compatible with GL, I asked myself how this approach can be combined with things like TreeList or HierachyList?