[Haskell-cafe] Problem with Gtk2hs

Andrew Coppin andrewcoppin at btinternet.com
Sat Dec 8 15:33:36 EST 2007

I just spent the evening writing a library that's a thin layer over 
Gtk2hs. It took an age to get it to compile, but eventually it worked. Yay!

When I ran it, I got this:

Test2: gtk/Graphics/UI/Gtk/Gdk/PixbufData.hs.pp:58:0: No instance nor 
default method for class operation Data.Array.Base.getNumElements

Er... wow.

OK, at this point, I am completely stumped. Any hints?

(Also, the documentation for Graphics.UI.Gtk.Misc.DrawingArea suggests 
that you may want to draw a Pixbuf using the pixbufRenderToDrawable 
function - but GHC complains that this function doesn't exist. I had to 
use drawPixbuf instead. Wow that has a lot of parameters... In 
particular, the final two don't seem to be documented. Interesting. 
They're both 0 in the "fastdraw" demo.)

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