[gtkmm] Drawing text on a DrawingArea Widget

[Markus Meier <m meier unibas ch>]

Dear all

I have to port my gtkmm-1.2 application to gtkmm-2.0. However, I have 
troubles to draw text on a Gtk::DrawingArea Widget with this new 
toolkit.
I can draw text in the widget, but not in the font I want (courier).

I figured out the following sequence from the gtkmm reference:

...
  Glib::RefPtr<Gdk::GC> gc;
  Glib::RefPtr<Pango::Context> pango_context;
  Glib::RefPtr<Pango::Layout> pango_layout;
  Glib::RefPtr<Pango::Font> font;
  Pango::FontDescription font_description;
  Gtk::DrawingArea *da;

  //create GC
  gc=Gdk::GC::create(da->get_window());

  //get pango_context of the DrawingArea and set font
  pango_context=da->get_pango_context();
  font_description.set_family("courier"); 
//"-*-courier-bold-r-normal--14-*-*-*-m-*-iso8859-1");
  font_description.set_style(Pango::STYLE_NORMAL);
  font_description.set_variant(Pango::VARIANT_NORMAL);
  font_description.set_weight(Pango::WEIGHT_BOLD);
  font_description.set_stretch(Pango::STRETCH_NORMAL);
  font_description.set_size(14);
  pango_context->set_font_description(font_description);
  font=pango_context->load_font(font_description);
  if(font==0)
    cerr << "Could not load font courier 14\n";
  //yes the font did load

  //now create the pango layout for the DrawingArea
  pango_layout=da->create_pango_layout("");

  gc->set_foreground(blue);  //Gdk::Color blue
  pango_layout->set_text("abcdefg");
  da->get_window()->draw_layout(gc, 10, 10, pango_layout);
...

However, no text appears on the screen. If I use
  create_pango_context() instead of get_pango_context() the text is 
drawn, even in the right colour. However my font settings are ignored.

What am I doing wrong? Any help is appreciated.

Best regards,
Markus

Markus Meier
M. E. Müller Institut
Biozentrum der Universität Basel
Klingelbergstrasse 70
CH-4056 Basel
Tel.: +41 61 267 20 91
Fax: +41 61 267 21 09