[Haskell-cafe] is gldrawingarea an instance of widgetclass

briand at aracnet.com briand at aracnet.com
Wed Dec 24 07:03:19 UTC 2014

I get this :

    No instance for (Gtk.WidgetClass GtkGL.GLDrawingArea)
      arising from a use of `Gtk.boxPackStart'

in code that was compiling at one point.
This is how I'm importing

  import qualified Graphics.UI.Gtk.OpenGL as GtkGL


  glCanvas <- GtkGL.glDrawingAreaNew glconfig

and use it thusly:

  Gtk.boxPackStart hBox1 glCanvas Gtk.PackNatural 0

boxPackStart wants something WidgetClass, and GLDrawingArea seems to be an instance of widget class.

The gtkglext hasn't been touched in quite a while.  I'm wondering if it's become out of date with the latest gtk.




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