VerticalPanelDropController broken when hiding Widgets in Panel

[GoogleCodeExporter]

Does the issue occur in "quirks mode", "standards mode" or both? If you
don't know, does your HTML page contains a DOCTYPE declaration?

Both.

What version of GWT are you using? 1.4.60? 2.0.4? Other?

2.0.4

What version of the gwt-dnd jar file or library file are you using?

3.0.1

What operating system(s) are you using? Windows? Linux? Mac?

Linux, Windows

Does the issue occur in web mode, development mode (formerly "hosted
mode"), both or don't know?

Both

What browser(s) do you use? Chrome, Firefox, IE, Safari, other?

Testet on Chrome 7 and Firefox 3.6

What steps will reproduce the problem? Please attach sample code if you
can.

I prepared a little demo:
http://r123.de/gwtdnd/GwtDndDropDemo.html

You can drag and drop all lines except the button. Pressing the button hides 
the 5th to 10th line. After that, dragging lines 10 and later won't work when 
trying to drop before line 5.

Source of the demo can be found here:
http://r123.de/gwtdnd/GwtDndDropDemo.tgz

Do you have a workaround?

No.

Original issue reported on code.google.com by r.g.sieb...@gmail.com on 22 Oct 2010 at 4:58

[GoogleCodeExporter]

Problem still occurs using gwt-dnd 3.1.0

Original comment by r.g.sieb...@gmail.com on 11 Apr 2011 at 4:26

[GoogleCodeExporter]

Workaround: for the hidden lines, do not use setVisible(false), but apply CSS 
with
width: 0;
height: 0;
visibility: hidden;

Original comment by r.g.sieb...@gmail.com on 11 Apr 2011 at 4:55

[GoogleCodeExporter]

Having the same issue with AbstractInsertPanelDropController
GWT: 2.4.0
gwt-dnd: 3.1.2

Neither the workaround, nor using the css style and setVisible(false) seem to 
work.
It's only possible to drag to the lower half of the FlowPanel and dropped items 
do not always appear on the dropTarget (though they are there and shown when a 
filtering turns them visible...)

Original comment by tringe...@gmail.com on 31 Aug 2012 at 4:03