[gnomemm] How to use Gnome::Canvas::Canvas

[Samuel Abels <spam debain org>]

Hello,

I have studied the API references and I am trying to create a simple
Gnome::Canvas::Canvas. Unfortunately I have not found much
documentation, so here is how far I have come:

MyWindow::MyWindow()
{
  using namespace Gnome;
  Canvas::init();
  Canvas::Canvas* canvas = new Canvas::Canvas;
  Label*          label  = new Label;
  // Draw a label widget:
  new Canvas::Widget(*canvas->root(), 0, 0, *label);
  // Draw a rectangle:
  //new Canvas::Rect(*canvas->root(), 1, 1, 50, 50);
  label->show();
  canvas->set_size_request(400, 400);
  canvas->set_scroll_region(0, 0, 400, 400);
  canvas->update_now();
  add(*manage(*canvas));
  show_all();
}

Drawing the rectangle, the program will exit:

GnomeCanvas-ERROR **: file gnome-canvas-shape.c: line 842
(gnome_canvas_shape_update_gdk): assertion failed: (gdk != NULL)
aborting...

Drawing only the label, the program will start, but the canvas is
displayed as an empty rectangle and the label widget does not show up.

Now I am sure that I am just not using this properly, but I have not
found any documentation explaining this.

Can somebody please help out?

Thanks!
-Samuel
-- 
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|      Samuel Abels       |   http://www.debain.org    |
| spam ad debain dod org  | knipknap ad jabber dod org |
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