Extending python to our own gtk inherited Widgets

[varuns]

hi
i extended python to my own widgets inherited from gtk.
But when i try to run command

python2.5 -c "import mygtk"

it displays following error

"TypeError: mro() returned base with unsuitable layout ('gtkmy.MyChoice')"
...
..
 
"** (-c:13962): WARNING **: couldn't make the type `gtkmy.MyList' ready"
"TypeError: multiple bases have instance lay-out conflict
(!) [13962:   33.658] --> Caught signal 11 (at (nil), invalid address) <--
(!) Direct/Thread: Canceling 'Fusion Dispatch' (13964)!
Aborted (core dumped)
"

my widget heirarchy is as shown
GtkVBox -- > GtkMyDisplayable --> GtkMyScreen --> GtkMyList --> GtkMyFileBrowser

what i think is python is trying to initialize GtkMyList first before its parent thats why the error "instance lay-out conflict". If i m correct than can any one help me out with a question:: how to serialize the initialization process? (ie parent class gets initialized before child class.) And if i m wrong than whats this error for?

kindly help

Varun

[bartonc]

That sure looks like it's coming from the C API and not from the Python that we all know and love.

By "extending", I'm guessing that you mean you are writing and compiling the extension in C.

[varuns]

i figured out the problem. I thought, i followed code writing standard of Gtk, but not i did some mistake and the .defs file generator (h2def.py) was unable to generate the "scheme" for interface (GTypeInterface) (i have to still figure that out). But i edited directly the generated .defs file.
Generated scheme for my interface looked like

;; -*- scheme -*-
       ; object definitions ...
       (define-object MyChoice
         (in-module "Gtk")
        (c-name "GtkMyChoice")
        (gtype-id "GTK_TYPE_MY_CHOICE")
       )

but it should look like

;; -*- scheme -*-
       ; interface definitions ...
       (define-interface MyChoice
         (in-module "Gtk")
         (c-name "GtkMyChoice")
         (gtype-id "GTK_TYPE_MY_CHOICE")
         (prerequisites "GtkMyImage") #----> quotes should contain object name of corresponding #included file;(i think so, not so sure, i just checked how pygtk people have written there .defs file). In my case its #include "gtkmyimage.h"   
       )

I made these changes and the error was gone.

By "extending", I'm guessing that you mean you are writing and compiling the extension in C.

yes, i m trying to write something similar to pygtk, as we can access gtk api's from python using wrapper functions and Python APIS like Py_ArgParseTuple, Py_BuildValue etc etc........, so that i can just use python scripts instead of long C code and also i m learning and using python because manipulation of data is really easy in Python.

Also i have posted solution for "undefined variable gdk_keyval_convert_case" for directFB at http://www.thescripts.com/forum/thread657353.html

[varuns]

generator (h2def.py) was unable to generate the "scheme" for interface (GTypeInterface) (i have to still figure that out).

hi
replying to myself..

i consulted authors of pygtk group and the information they provided is
h2def.py never generate scheme as define-interface, they generate it as define-objects. You need to manually edit it.

Also You could try defsgen.py:

http://svn.gnome.org/viewcvs/pygtk/t...en.py?view=log

which uses ctypes to generate .defs - its more comprehensive in
generating .defs.

else you can change manually object to interface and use scanvirtuals.py

http://svn.gnome.org/viewcvs/pygtk/t...ls.py?view=log

to retrive the virtual methods.

cheers