GdkWindow not a GdkDrawable?

[MacUntu]

I'm trying to simply create a 22x22px GtkImage from a Cairo context. After reading through tons of out-dated information I gave up with:

GdkPixbuf *pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, FALSE, 8, 22, 22);
GtkWidget *image = gtk_image_new_from_pixbuf (pixbuf);
GdkDrawable *drawable = image->window;
cairo_t *ctx = gdk_cairo_create (image->window);
/* do some drawing */ 
cairo_destroy (ctx);

Now image->window doesn't seem to be a GdkDrawable as I get the warning:

Gdk-CRITICAL **: IA__gdk_cairo_create: assertion `GDK_IS_DRAWABLE (drawable)' failed

Maybe all of this is crap - at the end I need a GtkImage and I have to use an existing paint-method that's using a Cairo context. Any help is appreciated.

[CharlesA]

Closed by OP's request.