drag'n'drop sample application

[John Emmas <johne53 tiscali co uk>]

Using gtk-win32, I'm porting a GTK+ application (originally written for Linux and OS-X) to the Windows 
platform and have been pleasantly surprised at how well it's all worked.  However, part of the app's 
functionality includes a drag'n'drop feature to move items from one part of the GUI to another part.  This 
feature works fine on the other platforms but doesn't work in Windows.  I see a drag icon when moving the 
item but when I let go of it, it remains in its original position instead of moving to the new position.

I've established that the individual elements of the drag'n'drop operation seem to be working.  e.g. if I 
grab an item and drag it, all the various 'drag_source()' functions get called, just like they do on the 
other platforms.  Likewise, if I drag an item from outside the app, I can successfully drop it onto a drop 
destination within the GUI.  So both parts of the operation work individually but they don't seem to work 
with each other.  My theory is that when I drag an internal item and let go of it, something must be 
preventing it from realising it's above a valid drop target.

Unfortunately, the app itself is very large and complicated so it's pretty difficult to figure out what's 
supposed to be happening.  Does anyone know of a handy example that I could use to study GTK+ drag'n'drop at 
a simpler level (with source code, obviously) ?

John