Regressions in Eclipse Drag & Drop

[MarioMarinatoSTech]

Initial disclaimer: this issue is an edited copy of the ticket 492861 on good old Eclipse Bugzilla. Some of the issues described on that ticket were solved but others still exist in Eclipse today. The ticket was closed some time ago, but as a RCP application developer I believe two of them are specially troublesome.

At some point during Eclipse 4.x, there were many regressions in the Drag & Drop system. This is an umbrella bug to track the regressions between Eclipse 3.x and 4.x.

• There used to be a drop region in the center of a stack (which occupied most of the stack's area) which would cause the dragged view to stack with the other views in that stack. Currently, dragging to the center of a stack is causing a split. This is not useful since stacking is much more common than splitting.

• Dragging a part back to the center of its own stack should cancel the drag operation. Currently it causes a split.

• If all the views are detached from the main window and the main window does not have an editor area, it's impossible to attach the views back. There used to be a drop region inside an empty main window, but it's not possible anymore.

See section 3.6 of this document for a diagram of the two missing drop targets.

Side note: the Detach command on tabs used to have a toggle state, and could be used to reattach a view back to the main Window. But it changed when Eclipse 4 was introduced. This is specially troublesome when you develop a RCP application with no editor area. In this case, if the user detaches all views, there's no way to attach them back to the main window. This used to be possible, either by un-toggling the Detach command or by dragging the view into the main windows. I always wondered why that decision was made. (see issue #273)

[jukzi]

@MarioMarinatoSTech do you plan to provide fixes?

[MarioMarinatoSTech]

@jukzi Hard to say, but I tend to answer no. I don't have too much free time outside my day to day job and I don't know if the company I work for would allow me to dedicate time to do that. I'd like to give it a try, but it doesn't seem likely to happen soon.