1. Python and GObject-Introspection
Yuren Ju <yurenju@gmail.com>

2. About me
●
http://about.me/yurenju
●
Hacking Thursday
●
KaLUG
●
Twitter: @yurenju

3. GObject

4. D-BUS
notify
Glade
GTK VTE

5. GNOME platform

6. Binding
Library
based on GObject

8. Use codegen to generate GTK C Wrapper for Python
gtk.c number of lines:
128,469

9. If GTK+ add APIs in new version,
python-gtk also need to upgrade for new APIs.

10. Implement in Python,
Also need to re-implement in Ruby, Perl, Java,
Javscript again.

11. GObject-Introspection

12. Original
python-gobject
metadata
GTK+
GTK+

13. GObject-Introspection
python-gobject
parser
metadata
GTK+
GTK+

14. Same metadata format
python-gobject
parser
metadata metadata metadata
GTK+GTK+ gstreamer
GTK+ ... GTK+

15. Parser + metadata = GObject-Introspection

16. tut-triangle
tut.triangle
+ get_color()
+ set_color()
+ get_centroid()
+ get_centroidu()

17. Metadata
Comments in Source code
g-ir-scanner
Gir XML file
g-ir-compiler
Typelib binary file

18. Comments in Source code
http://live.gnome.org/GObjectIntrospection/Annotations

19. Gir XML file

20. Metadata
Comments in Source code
g-ir-scanner
Gir XML file
g-ir-compiler
libgirepository Typelib binary file

21. python-gobject
PyGTK 2.24.0 has been released. This is a stable release supporting the GTK+
2.24 API. New users wishing to develop Python applications using GTK+ are
recommended to use the GObject-Introspection features available in
PyGObject. Existing authors of PyGTK applications are also recommended to
port their applications to PyGObject to take advantage of new features
appearing in GTK-3 and beyond.

22. gtk.c number of lines:
128,469

23. How to use GI?
from gi.repository import Gtk;

24. PEP-0302: New Import Hooks
Append finder to sys.meta_path,
Use finder.find_module() dynamic to find module.

25. Load module
●
find_module()
●
load_module()
●
Create DynamicModule
●
Module._load()
– Create self._introspection_module
●
IntrospectionModule => repository.requre to load typelib

26. Object
from gi.repository import Gtk
- Widget
- Container
Initial all items in Gtk - Window
Get info from ...etc.
repository.find_by_name()
If item is a object instance, Use a MetaClass
“GobjectMeta” to create a class wrapper
Finally, you have a Python Class to create Object!

27. Method – relative easy
object.method()
Call info.invoke()
g_function_info_invoke

28. Summary
●
GI Migrate metadata from language-binding to
library
●
python-gobject let you use GTK, GObject,
Gstreamer, VTE, Dbus,...etc.

29. 一人成佛，雞犬升天