If your first workaround (dummy callback) harmless to linux then why not, I've seen the usage of request_target in pygtk tutorial although demonstrate text data.

Still doesn't explain why gdk not handle bmp automatically. And I don't see them (request_*) implemented in gimp and inkscape, so it's hard to compare.

From what I understand right now :

request_image calls request_content with "content type" (which is called "target") "image/png".

When copying an image any typical (almost all) windows software (like MS paint) the only target returned by "request_targets" is "image/bmp". When copying from Gimp on windows, the only target returned by "request_targets" is "image/png".
That explain the difference. Still not the whole process...

In the following sequence :
- Copy an image from MS paint
- call 'request_contents("image/png",callback)'
=> The callback receive the outdated information

In the following sequence :
- Copy an image from MS paint
- call 'request_targets(request_targets_callback)'
- call 'request_contents("image/png",callback)'
=> The request_targets_callback receive only "image/bmp" BUT callback receive the right information.

Look like "request_targets" enable a sort of "auto convert" once it has noticed that the content is an image. Didn't found that code thought. I still don't know if request_targets is mandatory or not, so I don't know if it's a gtk bug or not.

Note : under pygtk/linux, I always receive "image/png" when copying image from any app (gtk or not, like firefox), that explain the win32 specific.

Ok, I've tried GIMP -> MyPaint, and It works here too (at least on 1.0.0)

I've uninstalled 0.9.1, so I didn't test it with 0.9.1.

When I tested the first time, I remember trying :
Any windows app -> GIMP = working
Any windows app -> MyPaint = not working

But I don't remember if I tried :
GIMP -> MyPaint

If I tried, it was not working, because I clearly remember it was logical (i.e. : everything paste to MyPaint was not working, while every paste to something else was working...)

Is it a PyGtk problem ? Or the way MyPaint use PyGtk ?

As I said, I failed compiling MyPaint on windows, but I know daily use python on windows, and I can try interacting with pygtk clipboard if that question is not answered.

I use my own gimp build for this testing:
http://dl.dropbox.com/u/2554170/GTKGraphics-1.0_Core2_Win32_Setup.exe

with mypaint 1.0.0

What happening is if the clipboard data is not pixbuf data Mypaint won't accept it (a.k.a from MS Paint) Gimp however appears to have their own clipboard system that will accept other format.

In my tests
GIMP -> MyPaint = working
MS Paint -> MyPaint = not working
MS Paint -> GIMP = working
MS Paint -> GIMP -> MyPaint = working

This bug fixed with latest GTK, or mypaint 061111git
please re-test http://mypaint.intilinux.com/?p=610

I try it between GIMP and MyPaint

Bakhtiar, better add a comment to the bugzilla bug then, with the exact gtk version and link here.

There seems to be active work being done on clipboard handling on then Win32 port of GTK, so there is hope that this bug will be fixed with newer versions. Eg.

https://bugzilla.gnome.org/show_bug.cgi?id=652239

I'm using 0.9.1 "official" build downloaded from http://download.gna.org/mypaint/mypaint-0.9.1-win32-installer.exe under Windows 7.

When I paste an image into the current workspace, it works as excpeted.

But when I paste another image (so the clipboard changed), it always paste the same image as the first one.

The clipboard works in every other applications (lets say gimp for exemple) and I of course checked the images I exepected to be in the clipboard really were there by pasting them into SEVERAL image editors (like gimp).